Advice on Automatic Solar Pool Heater Controllers

[big_g]

Just got some used solar panels (haven't plumbed them yet, no rush since it is November...). I was looking into Automatic Solar Pool Heater Controllers and hoping to get some advice on good models and/or at least good brands. Don't want spend more than around $300, but don't want a crappy system either...

Otherwise I'm just gonna use a 3-way jandy valve and a check valve and just adjust the temperature manually.

Thanks!

 

[jblizzle]

The Pentair Suntouch seems to be a nice unit with a few options that my Hayward automation does not. You can find it where it comes with the needed 3-way valve (either the solar version with a built-in check valve in the diverter like I got or a regular 3-way) and actuator.

You will also want to have 2 check valves (one after the filter and one on the solar return line) and will need a vacuum release valve.

 

[Isaac-1]

I agree with Jason exactly on this, the Pentair Suntouch is a nice unit, and if I had to do it over again I would probably get one instead of the Hayward Goldline AQ-SOL-TC which I have, which is priced similar to the Suntouch, and has many of its features, just in a clunkier less computerized design (smaller temperature display, mechanical timer, etc.). Having said that you will be hard pressed to find one with actuator and valve for under $300, however with some shopping you can get a basic Goldline GL-235 with an actutator and valve for under $200, maybe even under $175 in the off season (at least I was finding those prices when I went searching about 6 months ago). The GL-235 is probably the most popular solar controller on the market, it is no frills, does not even have a display, just a knob that is somewhat calibrated to set warmer or cooler.

 

[jblizzle]

I guess the real question is ... what is that $300 budget for? If it is ONLY for the controller and temp sensors, then you can get just about any of them for < $300.

But you also need:
- a 3-way valve (~$50)
- an actuator (~$75-$150)
- two check valves (~$100 for the good rebuildable ones for pools with less head loss)
- VRV ($15-$50)

So you are looking at close to $300 without the controller or any pipe and fittings.

 

[big_g]

Thanks guys! Perhaps I should have explained what I needed a little better...or at all...

I simply have a pool with some solar heating panels on the roof. I don't need anything else but a way to keep my pool at a set temperature (without having to walk out there all the time and fiddle with a jandy valve).

Here is an architectural-quality drawing of my setup... Based on this, I'd need the following, correct?:
2 check valves,
1 temperature controller,
2 actuators.

Is that it?

 

[Isaac-1]

You should only need one actuator from that drawing, the solar return does not need a 3 way valve, just a T with a check valve to prevent backflow. Also you may only need 1 check valve depending on if your filter has a built in check valve to prevent backflow to the pump, some do, most don't. I know my Hayward Perflex DE filter has one. For ideas on solar plumbing look at the animations at http://www.h2otsun.com/auto.html also see http://www.h2otsun.com/PG5ht.html at the same site

 

[jblizzle]

It should go pump > filter > check valve > 3-way solar valve > to solar panels > solar panels > from solar panels > check valve > Tee back into to normal return to pool.

So you need:
2 check valves (to prevent backfeeding the filter and the solar panels)
one 3-way valve to divert the flow to the solar (maybe you already have this?)
one actuator on the above 3-way valve that is attached to the controller
one solar controller that will have 2 or 3 temperature sensors and will open close the actuator as required.

That Suntouch may actually have a timer built into it as well.

 

[big_g]

It should go pump > filter > check valve > 3-way solar valve > to solar panels > solar panels > from solar panels > check valve > Tee back into to normal return to pool.

So you need:
2 check valves (to prevent backfeeding the filter and the solar panels)
one 3-way valve to divert the flow to the solar (maybe you already have this?)
one actuator on the above 3-way valve that is attached to the controller
one solar controller that will have 2 or 3 temperature sensors and will open close the actuator as required.

That Suntouch may actually have a timer built into it as well.

So I need a regular old 3-way jandy valve, remove the manual lever on it, and mount the actuator to it?
Thanks!!!

 

[jblizzle]

Yes. Or get the Pentair solar 3-way valve that allows the panels to drain a little better when the pump is off.

 

[big_g]

Ok, I found this:
[attachment=0:3hcb6m04]gl235.jpg[/attachment:3hcb6m04]

The SunTouch is a very nice unit, but I could not find the "kit" for under $320. Not sure it is that better than the GL-235 (is it?).

I'm looking into this since I am afraid my pool is going to get way too hot in the summer. (Solar panel sqft is around equal to or greater than pool surface area, plus I live in Tucson, AZ).

 

[Isaac-1]

You can also use solar panels to radiate heat at night as pool coolers. I think you can get that same GL-235 kit cheaper on Amazon, and likely even less other places. (I think the GL-235 has a jumper for cooling mode but you have to remove the front panel to set it, still not a big issue if your only doing it a couple of times per year (start and end of the hot season))

 

[Isaac-1]

One question here that has not came up, what type, size and model of pool pump do you have? I ask as the GL-235 does have some limitations in pump control since it has a built in relay which is limited to 1 HP at 115V or 2 HP at 240V

 

[big_g]

One question here that has not came up, what type, size and model of pool pump do you have? I ask as the GL-235 does have some limitations in pump control since it has a built in relay which is limited to 1 HP at 115V or 2 HP at 240V

Pretty sure I have a 1hp pump (it is a Pentair Superflo). Just curious, my pump is 1hp, but my actual motor is like 3/4hp. So does that simply mean that my pump is capable of 1hp, but I'm only utilizing 3/4 of it? (Yeah, I'm still kind of new to all this... )

 

[jblizzle]

What is the listed service factor (SF) on the motor? The true horsepower is the HP*SF.

 

[Brentr]

Big_g we have the GL-235 and it works great. We just set the temp and it automatically comes on and off pretty much like your house cooling system. It is very simple and we love it. In the winter time we turn it off and the pool pump is then activated by the timer. BTW the GL-235 overrides the timer when we have it set in the ON mode. Yes it does have a cool feature but we never had that feature hooked up as we love a very warm pool. Solar definitely has extended our swim season. Look at our solar install in the sig bar.

 

[big_g]

What is the listed service factor (SF) on the motor? The true horsepower is the HP*SF.

Ok, so I had it backwards I think... The pump appears to be a 3/4hp, and the motor is a 1hp. (Although the sticker on the motor was pretty faded, but it looked like a "1"...).

Thanks for the info Brent! The way you use it is the exact same thing I'd do. So I may just go with the gl-235 since it is the cheapest and most commonly used.

 

[big_g]

Ok, one last question. Can I mix and match parts? Example: The gl235 controller, brand X actuator, and brand Y 3-way valve? I've been looking and I see a lot of good deals on just the individual pieces, so I was just wondering... Plus I thought I could start by putting in simple manual 3-way valves first, and then if later on I find that the pool is getting too hot with solar always on (as I expect), then I'd get the controller. But I wouldn't want to get a 3-way valve that won't work with the gl-235 actuator. Did all that make sense...?

 

[Isaac-1]

Yes and no, there are some that can be interchanged and some that can't. Mostly it is a matter of the same valve or actuator being sold under different brand names though. Also remember having a solar controller is not just about keeping the pool from getting too hot, it is also about making it warm as efficiently as possible. This means not running it at night when it would radiate heat (unless you want to use it to cool the pool in the summer), and also it means the ability to automatically turn off the solar heat when there is a short term potential for radiating heat, a mild effect of this would be when the sun went behind a heavy cloud on a cool day, a worse example is like in my area where we commonly get spring and summer time thermal thunderstorms in the afternoon, there is nothing like pouring nearly ice cold water onto a solar panel to cool it off.

Ike

 

[big_g]

Yes and no, there are some that can be interchanged and some that can't. Mostly it is a matter of the same valve or actuator being sold under different brand names though. Also remember having a solar controller is not just about keeping the pool from getting too hot, it is also about making it warm as efficiently as possible. This means not running it at night when it would radiate heat (unless you want to use it to cool the pool in the summer), and also it means the ability to automatically turn off the solar heat when there is a short term potential for radiating heat, a mild effect of this would be when the sun went behind a heavy cloud on a cool day, a worse example is like in my area where we commonly get spring and summer time thermal thunderstorms in the afternoon, there is nothing like pouring nearly ice cold water onto a solar panel to cool it off.

Ike

Excellent points! I think you convinced me.
So I'm looking to buy Jandy neverlube valves and the GL235 controller and actuator. Would those two brands be compatible?

 

[jblizzle]

Unlike Isaac seems to indicate, I can not think of any pool actuator or 3-way valve combination that would not work ... assuming you get a true pool 3-way valve (Hayward, Pentair, Jandy). Might be cheaper to buy the controller, valve, and actuator separately.

FYI, I have a Hayward controller, Pentair 3-way solar valve, and Intermatic actuator (by far the cheapest actuator out there) ... with no problems (well besides the actuator having a crack in it that made it not stop turning, Intermatic sent me a replacement with no issue).