Leak Sensor and Open / Close Sensor Heartbeat Monitoring, Low Battery Monitoring

In the last week I finally got the programming done for heartbeat monitoring and low battery monitoring. I based my programming on an excellent post on the Universal Devices forum by Belias here. I won't reproduce the programming here - it is very well discussed on the forum, but I will add some information about how I integrated it into my system.

Once I had the heartbeat programs operating, with the system variables programmed for each leak sensor and door sensor, I added a line to the notification program that notifies the user of a system fault or leak. This line controls an "Alert Notfication" keypad key scene, a "Water Leak" detected keypad key scene, or a "System Fault" keypad key scene, as appropriate.

For example, when a low battery status is received, or a missed heartbeat is received, an email notification is sent to my email address. In addition, I have an visual indication on my 8 button keypads at my entrance doors and bedroom keypad of the fault.

System Fault Indicator activated - Signals a Missed Heartbeat, Low Battery Indication on a Battery Powered Wireless Insteon Sensor. By pressing the system fault key, you can cancel the fault indication on all keypads where this signal is activated.

Check out my post on custom labelling Insteon Keypad buttons here.

I have set up these keys as controllers for the Alert scene - so that I can cancel the fault or alert on all keypads by toggling any keypad key. With the way the programs are written, they will update the notification every 12 hours - so you would have to cancel the fault indication on the keypad every 12 hours (or allow it to stay lit) until you correct the issue with the wireless device causing the fault.

Sources and Links

I hope you found this post useful. Feel free to ask questions in the comments section below. I answer all questions.. My go-to place in Canada for Insteon automation components is Aartech.ca.

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Insteon Powerline Modem (PLM) Issues - Appeal to Smarthome to Improve Upon the 2413S.

For about 2 months now I've been noticing some Insteon system / network issues - sometimes, the exterior lights won't come on in the evening. Sometimes, they won't go off. Sometimes, certain lighting scenes wouldn't function when commanded with a double tap (Fast On or Fast Off). I upgraded my EZIO6I to a pair of EZIO2x4 input output devices - but when I installed them, they wouldn't give real time status updates in my PLM. An hour with Smartenit tech support, two factory resets of the EZIO2x4 units - and then I had my real time updates in my PLM.

A few clear warning signals appeared at this time when I was trying to get the EZIO2x4 units linked up properly to my PLM. The first occurred about 3 weeks ago - when the PLM completely lost its link table. For Insteon novices - it's important to understand that most of your automation logic occurs directly device to device when using scenes - even when you set those scenes up using your ISY 994i. All the ISY does is set up the link tables in each device to communicate directly with eachother. E.g. - I have installed some Micro open/close modules in all my bifold closet doors to automatically turn on the closet lights. I've set up the controls using scenes - with the open / close modules as the controller. In this case - when the micro open / close module changes state - it communicates directly with the linked Insteon light switch - and doesn't rely on the PLM to do anything.

However, anytime you write a program in your ISY-994i to run what/if scenarios, or timers, the proper functioning and execution of the results of your program rely on your PLM to send those commands out to your Insteon network for the desired action to take place. This turns out to be a significant weak link. I installed an insteon controlled water shut off valve - whose off control is commanded by an ISY program based on the results of the inputs of eight Insteon wireless leak detectors. So - when my PLM lost its link table 3 weeks ago - it also lost it's capability to communicate with the IOLinc which controls the water shutoff valve. Needless to say - the protection of the system was defeated by a single point of failure in the system.

When my PLM lost its link table a second time - I knew that something was going wrong with it. It was a 6 year old Smartlabs 2412S manufactured in the 23rd week of 2008. I did a bunch of research on the Universal Devices ISY forums (an excellent source of information) and found that the current generation PLM - 2413S - had some known power supply issues - the power supply would fail fairly predictably after about 2 years of use. I was interested in upgrading to the 2413S - apparently it runs a bit faster than the 2412S. However, I did not want to purchase a PLM that would predictably fail in a short period of time. Replacing a PLM takes about one to two hours - you have to backup your ISY, install the new PLM and reboot, and then restore the new PLM. Depending on the extent of your system, this can take a significant amount of time. Then - one by one - you have to put all of your battery powered devices into linking mode manually - and write updates to them so that they have the new PLM network address. In my case - that means rounding up all my leak sensors - and going to the closets and doors one by one to put the open / close sensors into linking mode. 2 hours to reset a PLM - and I've done this three times in the past three weeks. I decided to look for an NOS (new old stock) 2412S on eBay, and found a vendor selling 10 of them for a reasonable price. It was at my house in three days, installed the next day - and all my Insteon network flakiness seems to have been fixed. No issues so far with scenes not completing themselves, or fast on  / fast off triggers not executing. My old 2412S lasted 6 years - if I can get 4 years out of this new one, I'll be happy.

So - some constructive criticism on the 2413S PLM. We're using this device and increasingly relying on it for home security, loss prevention, garage door operation, energy management in addition to straight convenience. The first criticism is that the gradual, progressive failure mode of the PLM associated with failing power supply components inside the PLM has no definitive failure warning. Your system simply starts losing reliability, until you eventually have a link table loss which then manifests itself by loss of functionality in your system. First, you have to notice something isn't working correctly. Then, you have to troubleshoot it, realize you MIGHT have a PLM issue, then troubleshoot some more until you decide to replace the PLM. Time lost in my case - maybe 10 hours. So - the PLM should have some form of self-diagnostic routine and be able to signal a performance problem - blinking red light, message to your ISY - when it detects that it is failing. Ideally, the PLM should have internal redundancy - so that if it detects that it's main circuit is failing, it fails over to a backup circuit that can continue running your network reliably.

I really appreciate my Insteon network - and the conveniences it brings with lighting control, security, and so on. However, I have absolutely lost my patience for the amount of time I lose trying to troubleshoot and keep the sytem working. I have two kids - I'd really rather be doing something else on a Saturday than troubleshooting sporadic communications issues that may be related to a failing PLM. So - consider this a call on Smarthome to do something about the single point of failure in all our home automation networks - the PLM.

The second conclusion to take from this? Be very aware of the limitation of the PLM with regards to any mission critical applications you have it controlling in your home. For example - shutting off the water supply in the event of a leak detection. Or - relying on it to relay smoke detector alarms to your alarm monitoring company. When you are adding a function to your Insteon network - take into consideration the reliability of your network and the possibility of a single point of failure event. There are some good program examples on the Universal Devices forums that monitor the heartbeats of your leak sensors in order to give you a warning of a missed heartbeat, a low battery, etc. Put these programs in place in your network. If your PLM link table goes down - such a program would then be inundated with missed heartbeats, and within 36 hours you would have indication of a widespread network problem, helping to link it to a PLM issue.

There's my Sunday morning essay, a month in the making with my trials figuring out some seemingly random communcations issues. I don't mind spending $80 to replace the PLM, however I very much do mind losing 10 hours researching and troubleshooting whether my existing PLM actually has gone bad. This is a perfect opportunity for Smarthome to improve their products, the reliability of their systems, the happiness and confidence of their customers. Let's hope they take the opportunity.

UPDATE - 6 MONTHS LATER - JUNE 2015

The 2412S that I was hoping to get a few years of life from, just failed after 6 months in service. Now that I know what to look for - it's easy to see the signs of a PLM that is failing. My double tap commands on my switches start becoming unreliable - sometime they work, sometimes they done. The automatic water shutoff valve stops working on a water leak detection command. The monitoring programs for the leak sensors and the closet door sensors start reporting missed heartbeat messages. As soon as everything starts operating "flaky" - there's a problem with the ISY PLM. I thought back to the amount of time I lost trying to reload the link table in the PLM, restore the PLM, try to eke a bit more time out of it - and I couldn't bring myself to try to reset it even once. Interweb order to Aartech.ca - new 2413S PLM with the request they confirm delivery of a hardware version 2.0 or greater. 2 days later - the 2413S arrives, hardware version 2.1. And a full evening of swapping the PLM, and getting all the battery powered devices to relink up.

People are reporting on the forums better reliability with the new 2413S, hardware version 2.0 - but it will really take 2 years before we really see if these are made more reliably. Cross your fingers.

On another note - in the course of reprogramming the PLM - I couldn't relink the IOLinc connected to my water shutoff valve. Factory reset 3 times - can't communicate with the IOLinc. I've had this unit for 320 days - RMA to Smarthome to replace the unit.

I'll say it again - I love the things my home automation system does for me - but I can't afford the waste of time troubleshooting and replacing a faulty PLM and relinking battery powered sensors one by one. Here's hoping that these devices start being made more reliably so we spend more time playing with our kids, and less time with our significant others laughing at our obsession.

UPDATE 2 - 6 MONTHS LATER - NOVEMBER 2015

I installed the new 2413S - and less than 6 months later it's lost its link table - and nothing is working in my network. So tonight - I'm off to lose an hour of my time resetting it, reloading the link table, and relinking all my battery powered insteon devices one by one. Seriously - how about a redundant link table and a device somewhat more suitable as the heart of a home automation system?

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House Freeze Alarm / Furnace Failure Alarm / Pipe Freeze Alert

This is another feature that can be added to an Insteon / Universal Devices ISY994i system - a freeze alert to warn of a furnace failure, to prevent pipes freezing or other damage in cold weather. I negotiated an insurance rebate with this capability added to my system, so it's worth considering and looking into.

I had some unused inputs on an EZIO2x4 Input Output module, and was looking for a simple way to add a freeze alarm. I also had an unused Honeywell CT3500 digital thermostat, with single stage heating and cooling functions. This was very quick and simple to set up, starting with the installation of the thermostat next to my automation panel in my mechanical room in the basement. The Honeywell CT3500 runs off battery power - and the internal relays are switched on battery power as well - so you don't need to provide the thermostat with 24VAC to provide the dry contact capability.

Install the digital thermostat at a convenient location. Note the wiring connections - R and W connections give you a dry contact output for the heating activation of the Thermostat.

With the thermostat installed, and a dry contact wire pair connected to the R and W (Heat) terminals - it was time to install the thermostat face, and program the thermostat. I programmed the thermostat so that it would always return to the programmed temperature setting if anyone (kids) play with the setpoint keys on the face of the thermostat. The CT3500 can be set as low as 4.5 degrees C - but in my case I decided to give myself a bit more warning and programmed the heat setting on the thermostat to 7 degrees C. 

CT3500 thermostat programmed to provide heat at 7 degreex C - Label added to face of thermostat indicating function of the thermostat and a reminder to replace the batteries once a year. 

On the automation side, you have to have an input contact interface to your Insteon network. You could use a Smarthome IOLink, an EZIO module from Smartenit with input capability - the EZIO2x4, the EZIO6I, or the EZIO8SA. In my case, I had free inputs on an EZIO2x4 2 Relay 4 Input Insteon module.

The EZIO2x4 has four inputs per device - 2 inputs are dry contacts, and 2 inputs are digital / analog inputs that need to be configured for your application. Since my dry contact inputs were already being used for smoke detector and alarm interfaces - I had to use one of the digital inputs for this function.

The instructions for the EZIO2x4 advise you to use a pull up resister in order to convert a digital input to a dry contact input. Some research on the Smartenit forums provided some additional detail - you should use a 6000 to 10000 ohm resistor - connected between the 5V and the I3 or I4 terminals - in order to avoid drawing too much current from the 5V terminal. Then - your dry contact connects between the common terminal and the I3 or I4 terminal. Here's what the connection looks like with the pull up resistor:

Using a pullup resistor to protect the 5V terminal on the EZIO2x4 from overcurrent, when using inputs 3 or 4 as dry contact inputs.

On other thing I learned on the forums - that if you are not using the digital inputs on these EZIO modules - you should ground the input to keep them from floating, and initiating unneeded Insteon traffic on your network. If you look at the photo above, that's what the green wire is used for - shorting the I4 input to the common terminal. 

Once the thermostat has been programmed, it's time to program your ISY-994i. I set up a new notification message - House Freeze Alert - and created a new program to check the status of the I3 input on this EZIO2x4. Whenever the input changes to "On" that indicates that the thermostat has called for heat - indicating a temperature inside the house of less than 7 degrees Celcius. In that case - I have the ISY-994i send me an email to my email address, and a text message to my phone with the Freeze alert message. 

You could also tie this functionality to a monitored home alarm system - simply by using one of the output contacts on the EZIO2x4 to trigger a zone on your home alarm. Your alarm company could configure this zone to warn of the house freezing - and initiate a call out.

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Controlling an Electric Hot Water Heater with an Insteon EZIO4O Four Output Relay and Contactors

The electrical system in our present house is somewhat out of the ordinary - 400 Amp services, three separate 200A breaker panels, a whole house disconnect switch, a generator transfer switch, and one of the 200A panels is the generator emergency panel. In addition to the three 200A panels, there are two relay panels - one associated with the generator emergency panel which has 26 light circuits and has since been converted to Insteon with Insteon switchlinc switches and relays, and one panel with six 60A contactors, and about 8 light circuits, associated with one of the other 200A panels.

Contactors / Lighting relay panel associated with 200A breaker panel - circuit feeds enter through the nipple on the bottom right corner of the panel. Control wires enter in the top left.

The project for today was to add Insteon controls for four of the 60A contactors. I decided to use the Smartenit EZIO4O four output relay interface. The EZIO4O can switch up to 120VAC or 24VDC at 0.5A on four output relays, and can be controlled by the ISY994i Insteon controller. The contactors in this panel all have 120VAC coils - so I decided to use 120VAC as the control voltage and switch 120VAC directly with the EZIO4O.

Cabling was quite simple - I installed a standard electrical outlet in the device frame, to accept the plug in EZIO4O. I daisy chained a 120VAC control voltage to all the output positive connections, and then cabled the contactor coils with the EZIO4O negative connections. The EZIO4O lets you connect to both normally open and normally closed contacts. I decided to use the normally closed contacts - so that activating a relay on the EZIO4O would turn the circuit, and the contactor off. I wanted this system to fail closed - so that in the event of a control problem with the Insteon controller - I would still have hot water. 

Black wires are 120VAC Line feeds to the relays. Orange wires are the 120VAC load lines to the contactor coils. 

Once it was all wired up - I did some quick tests with the Mobilinc app on my phone - all the contactors switched virtually instantly when commanded by Mobilinc, and now I can work these devices into energy management programming. One of the circuits is my 60 gallon hot water heater. Another circuit is a steam generator for the master bathroom shower. The third circuit switches two circuits of 230VAC supplemental electric baseboard heating in the basement. The fourth circuit is unused for now.

My plan now that everthing has been connected and tested is to work these controls into the house vacation mode - when in vacation mode - turn off the hot water heater, the steam generator and the supplemental auxiliary heating in the basement. Quite often the kids will turn on the supplemental heat in the playroom - I'll be able to add a program to ensure it's turned off at night to help conserve energy. If you live with a service that charges peak electricity charges - then you could force the heating of your hot water heater in off peak times to save on your electricity rates. 

Steam generator circuit - top contactor - 50 gallon hot water heater - bottom contactor.

I have a "before" photo of this panel - what it looked like before I did the Insteon conversion two years ago. The contactors were always there, but instead of the Insteon switches, the panel had GE lighting control relays, which were controlled by an Industrial programmable logic controller (PLC).

6 Lighting relays, 5 Contactors - Original Setup for this Panel. Wires in the left hand compartment were the control wires coming from the PLC outputs. 

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Lennox Elite Series Thermostat Settings Optimization for Air Source Heat Pump Energy Efficiency

My new house came equipped with a Lennox X4147 Elite Series thermostat - a fairly high end touchscreen unit that can control up to three stages of heating and two stages of cooling. Last weekend I upgraded the Fan Coil unit's blower motor to an Evergreen IM electronically commutated motor to help increase the efficiency of the system. While testing the system, I was noticing how quickly the thermostat would call for emergency / auxiliary heat. If I increased the setpoint by 1/2 degree Celcius, the thermostat would shut off the heat pump demand, and call for emergency 2nd stage heating - in my case electric strip heating in the fan coil unit. This heat will cost 2 or 3 times as much as heat from the heat pump will cost (equivalent to the Coefficient of Performace of the heat pump performance at a particular exterior temperature, interior temperature, and airflow across the indoor evaporator coil). So - I started looking into the thermostat settings to see how I could avoid the emergency / auxiliary heating from kicking in so soon.

A little research lead me to the balance point settings on thermostats for heat pump systems. In order to be able to set the balance point - the thermostat needs to know the exterior temperature - to be able to know when to lock out the emergency heating, and when to lock out the thermopump. Setting these lockout temperatures can allow the thermostat to control when the emergency heating is engaged - so you're only using pure electric (or gas / oil) heat when the temperature is too low outside for the heat pump to make up the entire heating demand. This will improve the overall system efficiency - especially in the start and end of the heating season, when the exterior temperatures are still warm enough for the heat pump to deliver sufficient heating to the house.

There are a few ways that a thermostat can detect the external temperature. In the case of the Lennox X4147 - you need to install an external temperature sensor - the X4148 pictured below:

The Lennox X4148 Temperature Sensor and Bracket

The other method is to use an internet enabled thermostat, that can get the external temperature from an internet data source. The Nest thermostat is an example of a thermostat that doesn't require an external temperature sensor.

Since I already had a decent thermostat, I picked up the temperature sensor on Ebay for a reasonable price, and did the installation this morning. The instructions recommend that you use a separate, shielded cable for the temperature sensor installation, in order to minimize interference with other cables. It took me about an hour to route a signal cable out to a foundation wall through the basement.

Pulling a second, separate cable for the temperature sensor.

The temperture sensor pulled outside. I'll have to spend some time pulling this to a better location, out of direct sunlight and where the sensor could be buried with snow in the winter time. 

The final steps were to connect the cables, and program the thermostat to recognize the external temperature sensor.

The temperature sensor connects to the S1 and S2 terminals.

 Once the sensor is installed, wired, you can reinstall the thermostat face, and power up the system. Prior to engaging the heat pump or heating system, you'll need to program the thermostat to recognize the temperature sensor. You'll need to get into the setpoint programming interface - you can download the installer manual from the Internet for the full instructions.

Change installer setup number 340 to "2" in order to recognize the external temperature sensor and use it to control heat pump lockout settings. 

You can then  adjust your lockout settings for electric heat and the thermopump. Some caution is warranted here - you should check the specifications for your heat pump, and find a reasonable balance point based on the heat pump performance curve, and how well insulated / sealed your home is. You'll have to note the performance of the system in order to verify you have the correct balance point set. If you note when in ambient temperatures around the balance point you've selected your heat pump is not making enough heat for the interior temperature to meet the thermostat setpoing, you may need to adjust the balance point higher. You can research "Setting Heat Pump Balance Point" on the internet to find some further information on the thermodynamics on this. The Nest thermostat webside has a very good description on the relationship between balance point, and energy consumption.

I'm looking forward to reporting how this upgrade works with respect to energy consumption and performance. I'll provide updates over the coming weeks. 

Sources and Links

I hope you found this post useful. Feel free to ask questions in the comments section below. I answer all questions.

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One week living with the new Evergreen IM Furnace Fan Blower Motor

It's been one week now since I installed the Evergreen IM furnace fan blower motor. In a word - Awesome. I am amazed at how quietly the system runs now. When in fan mode for circulating air from the heat recovery ventilator - you can now barely hear the air moving through the ductwork - yet it`s circulating almost 900 cfm. The furnace itself in the basement now runs almost silently, just a slight air circulation noise, and absolutely no motor noise.

When the system speeds up to 1500 cfm when the thermopump is running, you can hear the air circulating from the ducts, but there is no duct ticking noise or rattling noises - which I attribute to the cleaning of the accumulation of crud off the blower wheel improving its balance, and also the operation of the motor. Again, in the furnace room, the furnace just hums, with barely any motor noise, and just the faint noise of air movement. 

What an incredible difference in comfort and noise reduction, and then you have to consider the energy savings. I`m looking forward to the next two energy bills so that I can check to see if there has been a meaningful reduction in energy consumption matching my estimates. 

The result of this powerful demonstration of speed control and EC motor energy savings is that I`ve now turned my eye towards my 4 ton heat pump installed out back of the house. This unit is a 13 SEER single speed heat pump that rattles like an old volkswagon bus. The noise from our patio has always been annoying to say the least, and I even drew up plans to construct a noise barrier around the thermopump to try to block the rattle and noise from our patio. Following the fan motor upgrade, I`ve not started researching whether I can get a similar noise reduction and energy reduction advantage from replacing the heat pump. 

From what I`ve seen - that looks to be absolutely the case. A simple upgrade to a 2 speed heat pump with electronically commutated fan motor will allow the heat pump to operate most of the time at a lower speed (first stage) mode at lower heat transfer rates, for longer times, but at reduced energy consumptions. The indoor fan blower will run at a corresponding lower rate - lower energy cost, and low noise. When the heat pump is running at the first stage mode, it`s noise should be dramatically reduced as well - which will result in much less noise on the patio. 

I`m pretty excited about this discovery, but I plan to do my homework first and try to estimate the energy savings before pulling the pin on a new heat pump. It looks like to get the benefit of one of these higher SEER two stage units - I`ll have to upgrade my evaporator coil to run on a newer refrigerant - right now I`m running on R22. 

That`s all for now - I look forward to publishing my research and making the decision on this upgrade sometime this winter. For now though - I`m also looking at continuouse energy monitoring using a Brultech energy monitor. Will be reporting on my research on that as well. I`m thinking it will be useful to baseline the existing HVAC system energy consumption prior to the upgrade, to be able to better measure the resulting performance. 

Sources and Links

I hope you found this post useful. Feel free to ask questions in the comments section below. I answer all questions.

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Upgrading to an Evergreen IM Electronically Commutated Furnace Fan Motor

This weekend's project was an energy efficiency project - upgrading the furnace fan motor in my 20 year old Lennox fan coil furnace (thermopump / electric heat). When we moved into this house two years ago, we embarked on a series of energy efficiency upgrades - increasing attic insulation. Increasing insulation around attic duct work to reduce duct loss. Improving the building envelope - by sealing gaps and adding spray polyurethane insulation at critical places. With the improved sealing, we also installed a heat recovery ventilator (HRV) - to constantly exchange fresh air from outside with stale air from inside the house. Since the house has a ducted ventilation system, the HRV was connected to the return ductwork and required the furnace fan to operate constantly when the HRV is exchanging air.

The furnace fan ran with a typical permanent split capacitor (PSC) motor, with a 3/4 hp rating. This motor draws 5.5 Amps at 230 Volts when running - for 1250 Watts of enengy consumption, 7 days a week, 24 hours a day. At $0.095 / kW-hr for electricity, this motor costs $1071 / year to run. The motor was installed to run at a single, high speed.

Some research lead me to the Evergreen IM electronically commutated (EC) motor. This motor is a brushless DC motor with permanent magnets, one of the most energy efficient motor types currently available (similar in design to the motors found in electric cars). All the electronics are contained in the motor housing itself, and the electronics and electrical connections have been designed to mimic standard HVAC fan motor leads, with "taps" for low, medium, medium-high and high speed. These taps don't connect to line voltage, rather, they are control lines that are used to instruct the power electronics how to control the motor speed electronically.

The Evergreen IM EC motor, with belly band mount installed.

Prior to purchasing the motor, I read the manual available online to understand its specifications, applicability to my furnace, and installation requirements. Investigating my current system I found my existing 3/4 hp motor to be installed with a shaft bearing mount - incompatible with the Evergreen IM motor. So I knew I needed to order a motor mount at the same time. Photos of the existing motor's data plate indicated that it was a "Frame 48" sized motor - the same size as the Evergreen IM.

Genteq sells a series of different sized motor mounts for its Evergreen line of motors - 10", 11" and 13". I got access to the current blower, measured the blower wheel diameter (11 1/2" in diameter), and realized I would require the largest mount - the 13" mount.

I shopped online, got pricing from Amazon and the usual suspects, but also called my local HVAC contractor - Ventilation PCP in Sainte-Julie. They provided a reasonable price for the motor and the mounts, and also some assistance in case I ran into any difficulty installing the motor. I felt that the little extra that I paid purchasing from my HVAC contractor might come in handy in case I ran into trouble, so I ordered the motor and it arrived from the distributor in a few days.

The first steps in replacing the existing motor is to baseline the performance of the existing fan, so that you can set the speeds correctly with the replacement motor. To do this, there are a few methods described in the Evergreen IM motor manual. I decided to do a Total External Static Pressure (TESP) test of my fan coil unit, and also do a Temperature Rise test of the 2nd stage electric heating circuit. These tests took about 2 hours total, taking my time to get it right. There are quite a few good youtube tutorials on how to do these tests, they are not complicated, if you are methodical it's pretty simple and straighforward. I'll list a few of my lessons learned below.

To perform the TESP test - you need an electronic differential pressure gauge. I borrowed a Testo 510 - very nice and simple to use. They cost about $200 on ebay to purchase, but since I don't expect to be doing this type of work very frequently, I didn't purchase one. The Testo reads differntial pressure in inches of water, and since the fan coil unit is pretty large, I used some vinyl tubing to run to my pressure test points - at the inlet (return) side of the fan coil - just before the thermopump evaporator coil - and at the outlet (supply) side of the fan coil unit - after the ventilation fan and electric heating stage.

My existing system ran at about 0.44 in H2O, which I understand to be a pretty good figure indicating relatively efficent (properly sized) ductwork. There are three principal returns, one from each level of the house that come to the return side, and three separate independant supply branches after the fan coil running to each level of the house. To do the test, I made sure all the filters were cleaned, all registers and dampers were open to minimize restrictions in the ductwork.

Testo 510 differential pressure gauge.

To do the temperature rise test - the procedure is relatively straighforward. Basically, by measuring the air temperature entering and leaving the furnace heating unit, and measuring the energy consumption rate of the heating system in Btu/hr - you can calculate the airflow of the furnace using a simple thermodynamic calculation. The Evergreen IM manual only suggests that you measure the temperature rise before and after the motor upgrade, so you can set the speeds on the Evergreen IM to match the temperature rise numbers (and therefore match the airflow). In my case, by also measuring the electrical consumption of the electric heaters, you can use the sensible heat calculation to do a reasonable estimate of airflow. I used my Klein CL1000 clamp meter to measure the power consumption of the heating stage - which ran at 85.3 Amps at 230 Volts - from which you have to subtract the fan power consumption (5.5 Amps), which left me with approximately 80 Amps of electric heat consumption. By the way - when you're doing this, you'll have the connection panel (or your electrical panel) open to be able to access a cable to measure current. If you're doing this - you'll need to be very careful about live circuits. If you're not comfortable with this - just avoid this altogether - you really only need to measure temperature rise.

Klein CL1000 Clamp Meter

 For measuring temperature rise, I used a digital meat thermometer (found in the kitchen). I found that with a 3/8" hole drilled in a duct, I could get the probe into the airflow pretty close to the supply and return sides of the furnace, and get a fairly accurate temperature measurement. It takes about 15 minutes for the furnace to come to a good equilibrium to allow you to take measurements. Then, each duct temperature measurement took about 1 minute for the reading to stabilize, indicating that the probe tempeature had matched the airflow temperature. If doing this again - I would purchase a second digital meat thermometer. They are not expensive, and by doing both the supply and return side at the same time, it would have saved some time in the process.

Digital meat thermometer for measuing temperature rise. 

The following photo is the meat thermometer inserted in the supply duct measuring the furnace outlet temperature (43.9 Celcius). Note that you have to place the thermometer out of direct line to the heating elements - otherwise heat radiation from the elements will throw off the measurement. You want to measure the temperature of the outlet air only.

Supply side temperature measurement using meat thermometer.

While I was at it, I also took a few duct outlet temperature measurements, and compared them to the mesurement at the outlet of the furnace. The difference in temperature between the furnace outlet and the supply duct outlets give you your duct temperature loss.

Once the measurements were taken and noted, it was time to let the furnace cool down a bit, and then get started with the motor swap. The first step is to cut power to the furnace (from all potential power sources, in some systems from multiple breakers, especially if you have a thermopump), open the covers, and note all the existing wire connections for the PSC motor. You'll be using some of these connection points for your new connections, so take a few photos and some good notes before you start disconnections. I intend to keep the old motor as a spare - so I'll need to remember how it hooks up to be able to reuse it in the future.

Once the old motor is disconnected, you need to remove the entire blower assembly from the furnace. In my case, this was pretty quick and easy (very accessible).

Blower with old PSC motor - note the shaft bearing mount - not compatible with the Evergreen IM motor. 

Once the blower was removed, the next step was to separate the blower wheel from the motor shaft. I started with a bit of penetrating fluid, and then checked to see if any of my automotive pullers would work on the blower wheel. None would fit, and I didn't have a blower wheel puller. So - once the motor was unbolted from the blower cage, I set the blower cage up on some 2x4 blocks, facing up, centered the blower wheel on the cage for good support, and then tapped the motor shaft with a block of wood and a hammer. 3 or 4 stiff blows, and the motor dropped out of the blower wheel.

With the blower wheel removed from the cage, I noticeds quite a lot of oily crud buildup - probably a mix of dust and lubrication oil from the motor bearings. I took the wheel outside, and scrubbed each vane of the blower wheel with a toothbrush to get rid of the crud. This is an important step in the process, and I'll explain why later on in this post.

Blower wheel in serious need of a scrub.

With everything apart, it's time to get the new motor installed. I carefully centered the belly mount cage on the blower cage, and marked my placement for new holes. NOTE THAT THE MOTOR NEEDS TO BE INSTALLED IN THE MOUNT TO MARK THE HOLES. If you don't have the motor in the mount - the motor mount will flex open too much, and your holes will be in the wrong place. 

Marking holes for drilling for the new motor mount

 I drilled the holes without the blower wheel installed, and then carefully cleaned the cuttings out of the blower cage. It was a bit fussy to get the new mount installed - the blower wheel had to be in the cage first, because it would not slip past the mount installed. It was a bit tricky reaching in behind the blower wheel to place the bolts - but everything went well working farthest from the blower outlet first. The last two bolts go in easy from the blower opening.

Installing the belly band mounting bolts. 

Once the mount is taken care of, install the motor in the mount and the blower wheel on the motor shaft. I put a small amount of anti-seize on the shaft before installing it in the blower wheel - just to help avoid it rusting together over time, and complicating future replacement. 

Prior to installing the blower, I had to replace the grommet leading from the fan / coil compartment to the wiring compartment, to fit the wiring harness for the motor. I found running the harness before installing the blower cage and motor gave me more space and made things easier. One nice thing about this motor is that the cable harnesses plug into the side of the motor and are removable. So - if you ever had to replace this motor, it's a simple swap out without the requirement to even access the wiring compartment of the furnace. 

New rubber grommet for the wiring harness.

The harness can be installed in the furnace before reinstalling the blower and motor.

Installation of the motor wiring harness.

Install the motor voltage jumper before reinstalling the blower and motor. If you get this step wrong, you can damage the motor, so take care with the instructions at this point. Here is the yellow jumper for 230V installed.

With the harness installed, replace the blower cage and motor.

Blower cage installed. Note the wiring harness run through the grommet to the wiring cabinet. 

With the blower reinstalled in the furnace, it's time to start making connections. Take your time, read the manual, and everything will go fine. I connected the two harness connections.

Harness connections and jumper installed.

I won't go into the details of the wiring connections, the manual does a fine job of describing the connections. All in, removal of the old motor, and reconnection of the new motor and startup tests took me about 2 hours. In my case, I connected the high voltage signal cables to give me 1/2 to 3/4 hp operation, and then connected the high speed signal wire to the thermopump "Y" call for first stage heating or cooling. I connected the medium high speed signal wire to the "W" emergency auxiliary heat connection (electric heat) in my case. There was no need to connect a low speed signal wire, the motor defaults to low speed when there is a voltage on the high speed signal wire, and no voltage on any of the other control speed signal wires.

This looks a lot worse than it really is - most of these wires are running back and forth between the electric heat elements and contactors. The thermostat connections are at the top right of the cabinet. 

The fan relay - I took the time to attach it to the side of the cabinet, because for some reason it was just sitting in the bottom of my cabinet. In my case - all of my 230V connections were made directly onto the terminals of this fan relay, and the motor harness is pre-terminated with spade plugs that fit perfectly on my relay. Made for very quick and easy connections.

With everything installed and running, I turned the furnace back on and ran a few tests. My first reaction was amazement at how quiet it was running in low speed mode - which I set up to run when my heat recovery ventilator is running. The furnace literally used to shake and rattle with the fan running at high speed all the time - and now, with a blower wheel scrubbed clean (and probably closer to factory balance) and the Evergreen IM motor - the furnace was now making less noise than the Venmar heat recovery ventilator - Amazing! Even at high speed the system was running much quieter than before. 

Zoom into this spreadsheet to see pre and post Evergreen Installation Calculations

The final step in the motor installation is to verify that all modes are working correctly, and very importantly - at the right speeds. It is absolutely critical that the ventilator speeds are well matched to the furnace operating modes - if you don't have enough airflow - especially with 80 Amps of electric heat in my case, or gas or fuel fired furnaces, you can quickly overheat the combustion or heating chambers, and hopefully your safety devices kick in and avoid damage. So - finish the installation with some Temperature Rise and TESP tests to compare to your previous blower speeds. 

When I completed my checks - high speed on the new Evergreen Motor in 1/2 - 3/4 HP mode gave me an identical TESP static pressure drop across my fan coil - indicating identical airflow. My temperature rise / sensible heat calculation gave me an airflow of approximately 1520 cfm on the old system - which is a good match for my 3.75 ton thermopump, using 400 cfm per ton of heating / cooling - indicating that I require 1500 cfm minimum.

For the identical airflow in my system - 1500 cfm - my fan current dropped from 5.5 Amps to 3.75 Amps - a 31.5% efficiency gain.

I used the fan law to calculate my airflow when in electric heating mode - medium high speed on the Evergreen IM. The fan law uses your TESP measurement differences to calculate your airflow differences in two cases. In my case, my temperature rise when from 38.7 F with the old motor to 42.1 F with the new motor in medium high speed - an acceptable increase in my case, considering that my fan power drops even further to 3.06 Amps - a reduction of 44%.

Conclusions

The final stunning measurement is the new power consumption in low speed mode. The fan law gives me a low speed air circulation of 834 cfm - a little more than half the flow of high speed - for only 0.63 Amps - a reduction of 88.5% energy consumption for more than half the high speed airflow. Since my furnace runs most of the time in this mode - my savings should be very significant.

By my estimates of the duty cycles - 50% of the time the thermopump or emergency electric heat is running, and 50% of the time only my air exchanger is running - I calculate that I'll save just over $600/year in reduced electricity bills. That gives me a payback of less than a year for the motor and mounting bracket.

A few final observations - a good cleaning of the blower wheel has resulted in the elimination of vibration in the furnace - even at high speed. No more rattling and chattering noise, and no rattles coming through the ductwork - what a huge improvement. At low speed circulation mode - the flow of air in the house is now imperceptable - even at night when the house is silent - what an improvement. And being in the furnace / utility room is now much quieter as well. I have a small workshop there, the reduction in noise is very welcomed. So far - well worth the research time, and all in - about 3/4 of a Saturday to perform all the pre and post tests, and the installation itself.

Sources and Links

I hope you found this post useful. Feel free to ask questions in the comments section below. I answer all questions.

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