Questions about single pump/single heater for spa-spillover pool

[WannaPool]

Hi- I am trying to help a friend regarding his new pool build. As my pool plumbing/pump configuration is different (2 pumps, 1 heater, solar panels), I am looking for some clarification on general heating/water routing for his configuration.

He has a spillover spa, a single pump, and a single large new electric heater/chiller (which is plumbed in, but electrical not hooked up yet). He is looking to plumb in a SECOND heater (an old propane heater) to independently heat the SPA. I believe he can do this all with his single heater, but need some clarification:

1) I assume during normal operation (spa spillover), he can set the big new electric heater to something like 84 degrees, and it will heat both bodies of water.
2) I assume that when he wants to use the spa, he will need to set his valves to pull water from the spa, and return water to the spa (effectively taking the main pool body of water offline for filtering), and can set the heater to something like 100 degrees. I am also thinking he may need to lower the pump speed, since he is effectively now only filtering/heating a small body of water.
3) Once done using the spa, he then needs to set the valves back to "spa overflow" operation, and sets the heater temp back to 84 degrees.
4) I assume his heater has 2 set points (one for POOL, and one for SPA).... my Hayward gas heater does, so perhaps this is standard?

If my statement above are correct, he can have his pool at 84 degrees, while having the spa at 100 degrees, without the need for a second heater. Even if he had a second heater, he would need to still perform the valve manipulation.

Is my logic correct here? Is this how things operate with a single pump, a single heater and 2 bodies of water (which can be made into one body of water, i.e. spillover?)

Thanks!

 

[HermanTX]

1) I assume during normal operation (spa spillover), he can set the big new electric heater to something like 84 degrees, and it will heat both bodies of water.

In spa spillover, the suction is from the pool and return back to the spa. Then the spa flows into the pool. So yes he can heat both bodies of water in this mode but it will take a long time initially. You do not state where you are located, so are you in a warm climate where heat loss is minimal? Also, most people do not operate the spa spillover all the time, it is normally done for an hour or so to keep the spa water fresh. Is the spa spillover running 100% of time that pool pump is on?

It may help to have a picture of his equipment pad because sometimes you can flow to both the Pool and the Spa depending how his plumbing was set up.

2) I assume that when he wants to use the spa, he will need to set his valves to pull water from the spa, and return water to the spa (effectively taking the main pool body of water offline for filtering), and can set the heater to something like 100 degrees. I am also thinking he may need to lower the pump speed, since he is effectively now only filtering/heating a small body of water.

In SPA mode, suction is from spa and return to spa so yes this will heat quicker. Usually you can set a temperature for SPA mode and POOL mode (or maybe Spillover mode). The pump speed needs to sufficient to activate the flow sensor.

3) Once done using the spa, he then needs to set the valves back to "spa overflow" operation, and sets the heater temp back to 84 degrees.

Correct or put in POOL mode to direct flow back to all the returns going to the pool and not worry about the Spa unless he plans to use it.

4) I assume his heater has 2 set points (one for POOL, and one for SPA).... my Hayward gas heater does, so perhaps this is standard?

Does he have automation? What is make and model of his pump and heater?

 

[WannaPool]

Thanks for the detailed response. My biggest unknown for a single pump pool is if under normal use of the spa WHEN HEATING, it is standard that there is no circulation/filtration in the main pool... and it seems like that is correct.

We live in Tampa, FL. I run my spillover all day. Its a nice peaceful waterfall. In all honestly, I was helping him fix his jet ski, when he mentioned he was going to add this old gas heater inline to his brand new pool and plumbing. And I got to thinking he doesn't need to. I only took a quick look at the plumbing, but it looked pretty standard. I can definitely get more information if needed.

He mentioned he has some kind of automation through an app on his phone, but I think it must only be for the pump and/or heater. Or perhaps the pool company has not completed it. There were no actuators on the valves, which he probably has about 10 of- Bubblers, Fountains, etc. I believe his return does have a 3-way, which will allow him to return 100% to pool, 100%, to SPA, or anywhere in between.

I would be willing to bet he wants to run the spillover all day- It is a rectangular spa which sort of sits inside the pool... so the spillover is 360 degrees over the top of the SPA walls... think of his SPA as a mini infinity pool, with spillover on all four sides.. really cool.

 

[ajw22]

Thanks for the detailed response. My biggest unknown for a single pump pool is if under normal use of the spa WHEN HEATING, it is standard that there is no circulation/filtration in the main pool... and it seems like that is correct.

Yes, that is correct.

He can only heat one body of water at a time. Even if he had two heaters.

If his spillover always runs then his pool and spa is a single body of water and he cannot heat the pool only. So he can heat the pool/spa or spa only.

A gas heater will heat the spa or pool faster then a Heat Pump will.