Showing posts with label Energy Conservation. Show all posts
Showing posts with label Energy Conservation. Show all posts

Low Speed AC Fan Dehumidification - Honeywell Prestige 2.0 Thermostat and Evergreen IM ECM Variable Speed Fan Motor

Now that summer is just about here - I've been working on fine tuning my summer dehumidification as part of my indoor air quality project. One of the issues that I'm working on resolving has been a faint musty odour in the house particularly in the summertime. Last summer I was dealing with 60% relative humidity (RH) levels in the house - even with the air conditioning running, and a small 18 litre/day humidifier running in the basement.
Honeywell Prestige 2.0 IAQ Thermostat - With low speed fan AC dehumidification - and the RH right at the setpoint - 45%
I'm running a 4 ton thermopump with a large Lennox fan coil unit in the basement. The system heats well in the winter, cools well in the summer, but the single speed 3/4 hp blower was consuming a fair bit of energy running 24/7 so that I could keep the heat recovery ventilator (HRV) to try to deal with the musty odour. I've done a couple significant upgrades to the system since last summer; i) upgrading the 3/4 hp split capacitor single speed blower motor to an electronically commutated (ECM) permanent magnet varable speed Evergreern IM blower motor - which is much more efficient at full speed, and magnitudes more efficient when running in low speed circulation mode; and ii) installing a Honeywell Prestige 2.0 IAQ Thermostat and Equipment Interface Module (EIM) to manage all aspects of HVAC control - especially to control humidification and dehumidification in conjunction with the heating and cooling system.

The Honeywell Prestige 2.0 IAQ thermostat has a control option for dehumidification using the low speed fan option of an air handler / air conditioner with a multiple or variable speed motor. There are three user defined outputs on the EIM that can be set up and customized using the configuration tools on the Prestige 2.0 IAQ thermostat. One of these outputs controls my HRV. A second output controls my new Honeywell Truease Bypass Humidifier and Damper, and the third output was unused. Since my humidity levels were running a bit better than last summer, but still higher than I wanted (52 to 55% RH) I decided to try configuring the third output to slow the blower speed down when air conditioning - Low Speed AC Fan Dehumidification - as a way of getting the humidity level indoors between 45 and 50% RH. The theory behind low speed AC fan dehumidification is pretty simple - by slowing the airspeed across the evaporator coil - this allows the evaporator coil to run a little bit colder, increasing the temperature differential of the return air and the evaporator coil, and improving the quantity of condensate on the evaporator coil.

So - the Evergreen IM motor uses speed "taps" that sense control voltage (24VAC) for the various HVAC functions - such as 1st, 2nd, 3rd stage heating / cooling, emergency heating, etc. and allows you to configure the motor to run different speed ranges for different heating and cooling functions to optimize the performance of your fan coil / thermopump combination. My configuration is described at the followling link - but simply, I had thermopump heating or cooling running at high blower speed, electric backup heat running at medium high speed, and HRV / circulation running at low blower speed. The control connection is simple - the Evergreen IM high speed "tap" which is the yellow control wire is connected to the first stage thermopump compressor control wire ("Y") from the thermostat (or EIM with the Prestige 2.0 IAQ). Since the Evergreen IM speed always defaults to low speed whenever it doesn't receive a higher speed control signal from any of its speed taps - all that is required to switch the fan to low speed when the thermopump compressor is running is to interrupt the speed tap on the Evergreen IM motor connected to the "Y" control wire. I thought I would have to install a small control relay to interrupt the speed tap, but the Honeywell EIM user outputs for low speed fan dehumidification is software configurable as a normally open or a normally closed relay. So - run the speed trap through the EIM user input - configure the relay as normally closed - and when the thermostat calls for dehumidification - it will interrupt the speed tap on the first stage compressor and force the fan to low speed operation. Since I already had a pair of unused wires running between my fan coil control box and the EIM - I didn't have to run any new wire, just make the user output connections at the EIM, and wire the pair in between the Evergreen IM speed tap, and the "Y" connections on my furnace. Simple.

One of the nice features of the Honeywell Prestige is the Equipment Interface Module (EIM) - Instead of all connections being made at the Thermostat in the living area of the home - all the connections are made at the EIM installed at the furnace or air handling equipment - and the Thermostat only requires power - control is all wireless between the thermostat and the EIM. 


So - how does it work? In a word - excellent. It took about a day for the average RH to drop from the 55% range to 49 / 50%, and then after the second day it's been running at my setpoint - 45% - during the day (when there is enough solar energy hitting the house that the air conditioning is running during the day). At night, the RH will drift up towards 49% because the outdoor temperatures are just a bit higher than the indoor temperatures, but this will improve as the summer gets hotter in the evenings. I shouldn't have any trouble now keeping my indoor humidity level below 50%, and I didn't have to resort to purchasing a larger dehumidifier, or a whole house dehumidifier.

I have to say that I still really appreciate the Evergreen IM variable speed blower motor - the HVAC system in the house runs silently most of the time now, and I still really like the Honeywell Prestige 2.0 IAQ thermostat - I like the display and integrated humidity control, I like that it controls my HRV and I don't need a separate, uncoordinated HRV control on the wall, and I like the continuous outdoor temperature and humidity display, along with the indoor temperature and humidity display. I also appreciate the ability to monitor and change the thermostat settings from anywhere - inside or away from the home,  using my smartphone and the Honeywell Total Connect Comfort app. (I still intent to write a post about this app.)

Now that the house has been below 50% RH for a few days since making this upgrade - I've noticed a reduction in the musty odour. It's not completely gone yet - we'll see how this evolves, but I'm thinking of adding a UV lamp to the ductwork to further improve the indoor air quality.

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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. 

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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. 

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

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%.


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.

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

Automating a 220V Pool Pump using a standard Home Automation Light Switch and a Contactor

I had some spare Insteon Switchlinc Relays remote control switches and wanted to control my pool pump remotely, and put it on a programmed run cycle based on the hours of daylight, sunrise and sunset. There are 220V controls that can be purchased for loads such as pool pumps, but they tend to be expensive. My solution was to use a standard remote control light switch 110V with a small contactor (industrial relay) to control the pool pump. In order to do so, you have to purchase a contactor with a 110V coil (that can be controlled using the light switch) and contacts rated for the load you need to switch (voltage and current).
Electrical boxes arranged for incorporation of the contactor
For the installation of the contactor I used a small 4 x 4" plastic junction box. In the photo above, note the small length of DIN automation rail that I installed in the bottom of the junction box. My small Siemens contactor had a DIN rail mounting interface, so that made the installation of the contactor in the plastic box very simply. I oriented in the cables entering the junction box so that the routing around the contactor would be direct and simple.
Devices installed - switches and contactor
 I used a double switch box to install my Insteon Switchlinc relay switches. The left switch controls a ceiling fan used to keep excess heat from building up in my pool shack. The right switch controls the coil of the contactor, switching it on or off. The bottom box is a manual disconnect switch which was originally used to control the pool pump motor. I decided to keep it - to give me a safety lockout switch to allow me to cut power to the pool pump, and avoid the possibility that automation turns on the pool pump while I'm working on the pump, cleaning a filter, etc.
Detail of the contactor installation
Here's the detail of the contactor installation. This small Siemens contactor cost about $20 on eBay, and has been running perfectly for about two years now. 

I've written a program in my ISY-99i which runs the pool pump for 8 to 12 hours a day, depending on the length of daylight on a daily basis (sunrise and sunset). In addition, I've added a program that switches the pool shack ventilation fan on anytime the pool pump is running, to ventilate excess heat from the shack. All works perfectly. This contactor also switches the line power for my Salt chlorination system - I'll write a separate post about that in the near future.