Showing posts with label Pool. Show all posts
Showing posts with label Pool. Show all posts

Running the Ecotech EZ Variable Speed Pool Pump Motor - GFCI Breaker Issues and Resolution

I've been upgrading my pool pump system with a variable speed motor from Emerson / Nidec / US Motors - the 3HP Ecotech EZ motor. I've described installing the motor on the pump, and the upgrade of the pool piping from 1 1/2" diameter to 2" diameter for better flow and lower restriction.

Ecotech EZ Variable Speed Motor installed on the Jacuzzi Magnum 1500 Pool Pump
The night that I finished the last of the 2" piping was when I reinstalled the salt chlorination cell. Then it was time to start up the pump for first time. Power on - then 2 seconds later the GFCI breaker feeding the sub panel in the pool shack tripped, and an error message appeared on the motor's LCD screen - blocked pump. The motor has a protection feature if the impellor gets blocked - it will prevent the motor from forcing against a blockage. I reset the breaker and tried a few times to get the pump running - then realized that I had installed the motor adapter plate backwards - jamming the impellor against the seal plate. So - 11:30 at night, and I pulled the motor from the pump and flipped the adapter plate, reassembled the pump and......the GFCI breaker still trips - but I no longer have the blocked pump error message on the variable speed control panel.

Ecotech EZ Motor Control Panel
The manual for the Ecotech EZ pool pump motor very clearly states that if you want the motor protected by a GFCI breaker, the pump must be installed on a dedicated GFCI circuit, not shared with other electrical loads. This posed a problem with my electrical system - my pool shack sub panel has 6 circuits - 4 15A lighting and power outlet circuits - one of which is the pool lights, and two 2-pole 240V circuits - one for the thermopump heater and one for the pool pump. When I moved into this house 3 years ago - only the pool light circuit was protected with a GFCI breaker. So - to upgrade the protection for the most economical cost - I protected the entire sub-panel from the feed from the house panel with a 40A 2 pole 240V GFCI breaker. The implication  of the requirement to have the Ecotech motor on its own dedicated GFCI circuit was to remove the GFCI breaker from the panel feeding the sub panel, and convert all the breakers on the sub-panel to GFCI breakers - an expensive upgrade. To try to avoid all this - I tried to get the pump to work with the GFCI breaker on the house panel - but even removing all the other loads on the sub-panel was causing the feeder GFCI breaker to trip every time I tried to start the motor. 

Ecotech EZ Motor Upgrade on Jacuzzi Magnum 1500 pump - with 2" plumbing upgrade
To get the motor running - I removed the GFCI breaker from the sub-panel feed. It started and ran fine, but with no GFCI protection. When anyone went near the pool, I shut off all the breakers on the sub-panel for safety, but this wasn't practical as a permanent solution. Incidentally - I did some research on other variable speed pool pumps - such as the Pentair Intelliflo pump - and it's installation manual also requires a dedicated circuit if the pump is to be protected with a GFCI breaker. 

I had two 15A single pole GFCI breakers from the original installation, which I put back into the sub-panel. Then I purchased a single 2 pole 20A GFCI breaker for the pool pump circuit. I installed this on the sub-panel, and it worked fine. Then I installed a second 2 pole 20A GFCI breaker for the thermopump. 

The point of this whole discussion is to warn anyone considering this variable speed pump upgrade that there may be electrical implications beyond just swapping the motor. Also - it's important to state that you should have this electrical work performed by a licensed electrician - or have a licensed electrician inspect your handywork if you decide to do this yourself. You want to ensure that the electrical systems are safely installed and will protect your family and friends from an electrical fault.

One other issue that I've run into is that I had my salt chlorination cell transformer wired with my pool pump motor - but I've had to separate the circuits in order to get the GFCI breaker for the pool pump to work. Also - the pump needs to be powered on all the time - the pump timing is now controlled by the intelligent controller on the motor, and not my central pool automation system. So I've decided to control just the salt chlorination cell from my central pool automation system - I'll program it to run on a function based on the length of daylight since chlorine degradation is a function of sunlight - and run the pool pump separately using the timer on the motor controller. I still have some wiring to get this up and running - if I run into anything interesting - I may do a separate post on this.

Once I got the electrical issues sorted out, the pump has been running now for about 2 weeks. I did some testing to check the current draw on the pump at various pump flows. The control panel modifies the pump speed as percentage of flow, and not as percentage of speed changes. Since the pump runs with a single set of programming from the factory, and every pump installation will be different with its own piping head - the percentage of flow settings on the motor will only be approximate on any system. 

What's interesting about this graph is that I can run at 75% flow consuming only about half of the full speed motor current, or I can run at 60% flow consuming only about a third of the full speed current. I wish I had taken the motor current measurement of the original single speed motor on the Jacuzzi Magnum pump - this new permanent magnet motor should be much more efficient at full speed. For the past two weeks I've been running the pump 24 hours per day, at 50% speed consuming less than 1 Amp of current. At this speed the sand filter backpressure is only about 3 psi - the power savings are impressive, and the filtration is very effective - water is crystal clear and my salt cell is performing well.

Measuring power draw of the Ecotech EZ motor using the Klein CL1000 clamp meter
Another feature of the variable speed motor is to be able to fine tune the motor speed to your vacuum and vacuum hose length, to avoid cavitation of the motor. On my previous setup with the single speed motor - the motor would cavitate whenever I was vacuuming. This would cause the pump to periodically lose prime, and suction on the vacuum. In addition, whenever I was vacuuming to waste early in the season to rid the pool of dead algae, the single speed pump was always running at full speed and drawing down the water level very rapidly. Now I can vacuum to waste at 40% flow - greatly reduce the loss of water and increase the time that I have to vacuum more effectively. I also expect that I'll be able to tune the motor to the barracuda automatic vacuum for peak performance, without using the bypass valve. 

Ecotech EZ Motor - Timer Controller is mounted directly on the motor housing
So - with the exception of the surprise expense on the GFCI breaker upgrade on my sub-panel - I'm very satisfied with this pump motor upgrade. My pump running at 50% flow is very quiet - I can't hear the motor at all outside the pool shack, and my neighbor's pool pump makes more noise now than my own. One other thing that I like a lot about this upgrade is the performance of the Jandy multiport valves - much easier to actuate by hand, nice clean looking installation. This is a positive upgrade - and I hope to see the results on my electricity bill at the end of the summer. 


Ecotech EZ Variable Speed Pool Pump Motor - Pump Installation and Piping Upgrades

Now that the pump is assembled with the new Ecotech EZ variable speed motor, it was time to get at the piping upgrades to help improve the overall system efficiency. I had a few serious weaknesses in my pool piping, particularly on the suction of the pool pump, and the piping feeding and exiting the thermopump.

Jacuzzi Magnum 1500 upgraded with Ecotech EZ Variable Speed Motor, Suction Side Piping Completed with 2 Jandy Valves
The existing pump piping layout wasn't very well done - it wasn't particularly efficient, and probably contributed to the pump cavitating any time the vacuum port was used. Note the vacuum port routing - which enters from the top right - 90 degree elbow, ball valve, 270 degree sweep, 90 degree elbow down into a T fitting, then off to the pump suction. All lines are 1 1/2" - so even if you decide to draw from the drain and the skimmer at the same time, you're contstrained by the 1 1/2" suction on the pump.

Old pump suction layout - skimmer bottom left, bottom drain top left, vacuum port top right, pump suction bottom right. 
I have 1 1/2" black poly pipe running underground to the pool. I'm not a huge fan of the insert barbed fittings - they're common for these applications but they neck the diameter down to 1 1/4 inch. I thought I would give a polyethelene epoxy adhesive a try, to convert to PVC fittings, made by TAP plastics in California.

Black poly lines moved to desired alignment, fixed with copper strapping. CPVC reducing slip elbows - 1 1/2" to 2" - fixed to the black poly line using TAP plastics poly epoxy.
I also converted the 1 1/2" poly lines to 2" at the 90 degree elbows where I made the transition from vertical to horizontal. See photo above. Once my suction lines were horizontal, I plotted the position of two Jandy 3 way valves facing each other, to allow me full flexibility in selecting and mixing the pump suction source. I used the 2 / 2 1/2" Jandy Valves to minimize restriction in the suction piping.

Suction side piping completed - Jandy Valves control suction source - skimmer, bottom drain, or vacuum port. 2" union fittings on the suction and discharge of the Jacuzzi Magnum pump. 
With the suction side piping completed - I then working on the transitions at the sand filter. I spent some time looking for a sand filter with a 2" multiport valve - mine was just a 1 1/2" multiport valve, and eventually decided just to keep the 1 1/2" valve. With the variable speed pump - the system would in the future be spending most of the time operating at a low flow speed, which would minimize the impact of the system restriction of the 1 1/2" multiport valve.

Jaccuzzi Multiport Sand Filter Valve Piping - 1 1/2" drain fitting on the close side, 2" rigid pipe discharging to the thermopump and salt cell on the far side. Pump discharge - sand filter feed line in the center. Unions on all connections. 
With the sand filter piped, it was time to work on the thermopump. The former layout had the thermopump piping side facing away from the pool shack, and 90 degrees away from the pool. In order to make the connections, about 30' of 1 1/2" hose made long circular connections between the sand filter and the salt cell.

The old Thermopump Installation - About 30' of 1 1/2" hose separates the Sand Filter from the connection to the underground hose where the Salt Cell will be attached to

The old Thermopump Installation - About 30' of 1 1/2" hose separates the Sand Filter from the connection to the underground hose where the Salt Cell will be attached to - right side of photo.
I moved the thermopump so that the piping connections would be facing the pool, and perpendicular to the pool shack, and then came up with a layout using the Jandy 3 way valves to control bypass and flow to the thermopump. 

The Thermopump was previously installed on the patio stones to the right. It's now moved into place next to the pool shack, just behind the outlet pipe for the pool jets. 

Jandy Valves will provide flow modulation and bypass isolation for the thermopump, with a much more compact piping arrangement.
Now, instead of 30' of 1 1/2" pipe between the sand filter and the salt cell, I'm down to about 10' of 2" pipe


I'm quite happy with the new piping arrangement and the upgrade to 2" piping. The only section of 1 1/2" pipe which remains is the section about 35' long between the salt cell and the first jet on the pool. I don't think I'll get the energy to make that upgrade for a while because of the trenching, so I'll wait until the pool requires major maintenance.

At this point, it was time to start the new variable speed motor - more on my next post.

Sources and Links

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


Ecotech EZ Variable Speed Pool Pump Motor Upgrade - Jacuzzi Magnum Pump

I've been working towards the goal of reducing my electricity bill by 33% - and I'm actually getting there. One of the largest loads besides heating and ventilation at my house is the pool pump. I have a typical single speed 1.5 HP Jacuzzi Magnum pool pump for an 18' x 36" rectangular in-ground pool. I like to open the pool early and close it late, and the kids love to swim. My estimates for running the Jacuzzi Magnum pump was around $500 / pool season full time. I've been running the pump on a time, for about 12 hours / day - so I guess I've actually been consuming around $300 per year in electricity. Thankfully, my marginal electricity cost is only about $0.095/kW-hr.

Ecotech EZ Motor installed on the Jacuzzi Magnum 1500 Pool Pump. The control panel is directly on top of the motor.
Last year I did a fair amount of research on the subject. and the key to saving electricity with a pool is to take advantage of pumping affinity law - which simply means that increasing the flow by 10% costs you 33% more in power. Similarly, reducing the flow by 25% will result in energy savings of approximately 50% - due to the reduction in friction losses by reducing the speed of the water in the piping (and importantly, across your filter element).

You can do this with multi-speed pumps - which can be standard wound-rotor pumps with a two or three speed tap - which will result in some savings, or even more significantly, with a electronically commutated permanent magnet variable speed motor, which are the most efficient commercially available motors. To take advantage of this simple principle, the state of California has mandated that new pool installations have as a minimum multi-speed pumps which default to low speed operation for filtration (California Energy Commission (CEC) Title 20 Appliance Efficiency Regulations).

My pool is probably a fairly typical installation for a 20 year old pool in the Province of Quebec - all the piping is 1 1/2 inches in diameter, and I have a 1.5 HP single speed motor, with a sand filter with a 1 1/2 inch multiport valve. My thermopump was added following the original pool installation - and it would have been difficult to imagine a less efficient plumbing addition to a system - to add the Thermopump - the pipe from the sand filter to the pool was extended by about 30 feet long in total - 1 1/2" piping - in a long serpentine.

So why upgrade just the motor, and not purchase a complete new pump? Because if you already have a decent pump - the motor will end up costing about 50% of the cost of a complete pump. If you're a bit handy, this isn't a particularly difficult upgrade. The hardest part may be the electrical part - and if you're switching the complete pump out - you'll need to deal with that anyway. My aim going into this upgrade is that the cost for the upgrade would be paid back within 2 years, and purchasing a complete new pump would not allow me to achieve that.

Starting point - Jacuzzi Magnum Pump with Single Speed, Permanent Split Capacitor Motor
So - to take best advantage of the variable speed motor upgrade, I also planned to upgrade as much of my piping as possible to 2" diameter, and relocate my thermopump to optimize the piping arrangement. I also planned to remove and replace all my 1 1/2" ball valves with 2 inch Jandy multiport valves - to simplify the plumbing and minimize the number of bends in the piping.

The first step in the project was to split the original single speed motor from the pump, and install the Ecotech EZ motor. This isn't terribly difficult to do, and it is also an excellent opportunity to replace your pump seal. The basic steps are as follows:
  • remove the pump from your system and disconnect the power;
  • split the pump from the motor by unscrewing the clamp ring between the motor and the pump;
  • unscrew the 2 screws retaining the diffuser, and lift the diffuser off;
  • unscrew the impeller by holding the motor end of the drive shaft, and unscrewing the impellor counter clockwise; 
  • lift off the seal housing (now is the time you would replace the motor shaft seals); 
  • unbolt the motor housing bracket (four bolts)
Preparing the Motor Housing Bracket for installation on the new Ecotech Motor
Note the clamp ring installed over the motor, with the seal plate installed over the motor housing bracket and motor shaft
Installing the impeller
Installation of the new motor is the reverse of the steps above, I won't go into details, there's quite a few good videos available explaining seal replacement on all types of pool pumps. Just ensure you take very clear note of the orientation of all parts during disassembly - photos will help. And - make sure you install the clamp ring right from the start - otherwise you'll be doing all the steps twice....

The Ecotech EZ motor installed on the Jacuzzi Magnum 1500 Pump - Ready to Install on the Pool
I'll write a separate post on the piping upgrade around the pump, sand filter and thermopump, Following that, I'll post about wiring up the new pump, the electrical considerations, power draw of the new motor, and the performance of the system. It's getting a bit too late to finish everything tonight.