Variable Speed Pool Pumps

I don't know the first thing about pool pumps, but I did just put a new single speed pump on my pool. It cost about 1/2 of what the new variable speed pumps cost. At $.09USD/ kWh I don't know what the payback period is.

However, in your case, monetary payback periods are not important. Wife payback periods are far more important to you.

Get the new pump and be sure your wife approves of it.

However, in your case, monetary payback periods are not important. Wife payback periods are far more important to you.

Always back down is what you're saying? Even if it doesn't make a lick of sense. Can't do it. Maybe that's why I'll be single 'till I die.

_{That's all right; I can do what I want whenever I want}

The ROI for this has got to be dozens of years, if that.

I have never seen, in private or public swimming pools, a need for, or a use for, variable speed pumps. I can think of no justification for a variable speed pump...

Wait a minute. I just installed for a friend a solar-powered pool pump. This is definitely a "variable speed" pump- the speed depends on how bright the sun is (or the angle it makes to the collector, etc.). Fortunately, I was able to convince him to leave the old pump hooked up to compensate for the variation in speed. No word yet on his electric savings- I suspect it is much less than anticipated (i.e., he is not bragging about it)...

I understand the need for variable speed pumps when dealing with pressurized water systems. Grundfos and Franklin are two of the bigger players in that field. They are based on monitoring the pressure and increasing or decreasing the speed of the pump to maintain constant pressure. The bigger the demand or flow of water the faster the pump turns. In fact they are also called constant pressure pumps. If you want to maintain pressure of say 70 psi and not have showers slow down when other taps are opened, then these are the types of pumps you should purchase for your house pressure system.

Pools are a whole different matter. As pointed out there is a need to move water to turn over the volume of the pool. Most pumps and your 1 hp pump will move water at constant pressure. The head will only vary with filter clogging and usually you will backwash before flow will become an issue. Filter back washing can also be done automatically based on the loss of flow through the filter. You see the flow loss as an increase in pressure on your filter. However these losses are very small compared to even a standard house demands with various demands (washing, showers, toilets, irrigation etc). A variable speed pump on a pool seems a big waste of time. Mandated? Why? Or is this April Fool still.

While VSD's have certain benefits and sold with the benefits highlighted, they DON'T tell you of the downside. Harmonics. These little things called "Harmonics" will cost you more in the long run, unless you buy a mitigation unit, only a small thing, but they can be worth it.

I suggest that you look at your power bills before and after to see if you've saved anything with this VSD for your pool pump.

I too thought this would be a better option, but I took it that "she who must be obeyed" had already made the OP's mind up for him.. and the no matter what the counter argument would be.. "we are having the speed controller!".. end of!

Hence my comments regarding the "before" and "after" power bill.

In a nut shell you only really save money when the thing is switched off....

Replacing a pump with very little technical or economic justification is not very environmentally friendly. The energy cost to make a new pump, and the energy footprint for disposal of the old pump, will far outweigh the additional energy saved by replacing your pump before it fails.

So you can sit back and do nothing, providing that you can satisfy your wife that this course of (in)action is saving the planet.

I have a two speed pool pump, and I like it because I'm gone for most of the day and I can leave it on slow speed. However, slow speed does not circulate the water like high speed does.

A little off-topic, but for those of you that do own pools, here's a suggestion. The hoses they sell for the pumps are pretty cheaply made, yet are always failing. I replaced mine with PVC pipe, and used rubber connectors with regular hose clamps so I can remove it every winter. The larger diameter and smooth bore has given me much more water flow even at the slower speed. To anyone looking to save a few pennies on electric, a two speed pump and PVC could be an ideal solution.