Am spec'ing out my pool to PBers and want to option solar?

[surferbum]

I am shopping my pool needs to PB's and am planning on putting in an option for future solar-heating. I am putting the pool in North Scottsdale, AZ. There will be hardscape between the pool and my single-story house. Will put a cover on the pool when not in use primarily to reduce evaporation. Couple of questions:

1. What should I specify to the PB for this solar option? I expect I need to have piping under the hardscape. Two pipes? What diameter? [/*:m:bot7mf43]
2. What can I expect for a temperature increase with solar heating in my area? [/*:m:bot7mf43]
3. If I want the pool to be 80*, how many months will solar extend my pool use? [/*:m:bot7mf43]
4. What have others paying for a system in my area? [/*:m:bot7mf43]

 

[jblizzle]

Re: Am spec'ing out my pool to PBers and want to option sola

1. Spec two 2" pipes stubbed out to the house. You will also need a 3 way valve on the solar supply and a check valve on the solar return, but that could be later.

2. Hot. My pool is currently over 90. Depends on number of panels and exposure.

3. At least 7 months, more if you use a cover.

4. Likely $4-5k. Unless you do it yourself. Mine was about $1500 using used panels I bought off craigslist from someone up by you.

 

[Isaac-1]

Re: Am spec'ing out my pool to PBers and want to option sola

What Jason said, but I would also suggest looking at http://h2otsun.com/ They have lots of information on installing solar heat systems (of course it is mostly directed at using their product, but there is still lots of good general information) Most information you will find online will talk about retrofitting solar heat to an existing pool, one of the articles at the link above shows how to plumb in a better way with an additional separate return line for new pool construction (I don't recall if it is in their installation instructions or one of their additional reading items).

Ike

p.s. I do not have the above mentioned panels, I did consider them when I recently replaced my old panels, but ended up going with Techno-Solis brand panels as they were less than half the price while still being a reputable brand name panel.

 

[surferbum]

Re: Am spec'ing out my pool to PBers and want to option sola

1. Spec two 2" pipes ... 4. Likely $4-5k ...

Thanks.

What Jason said, but I would also suggest looking at http://h2otsun.com/ They have lots of information ...

Thanks.

 

[bmoreswim]

Re: Am spec'ing out my pool to PBers and want to option sola

We too ran 2 - 2" pipes from the equipment area over to an area that may house a future pavilion which solar could be installed on.

Our PB also gave an off the cuff number on the cost and it was similar. Higher than I expected though.

 

[surferbum]

Re: Am spec'ing out my pool to PBers and want to option sola

What Jason said, but I would also suggest looking at http://h2otsun.com/

I looked at the website and was very interested in their discussion of pump size and plumbing. One takeaway that I have from the pump size was that if the pump develops too much pressure then it will damage itself in such a way so that it becomes more inefficient in the future. A second takeaway was that solar cells are more susceptible to pressure-related damage then I expected. Unfortunately, I am just confused about what pump HP to get if solar is in the future for an addition other then variable speed capability.

 

[Isaac-1]

Re: Am spec'ing out my pool to PBers and want to option sola

Correctly sizing a pump for solar use while minimizing pressure the panels are exposed to is a challenge. Therefore in a new installation it may be smart to add an additional return fitting plumbed for future use that would be dedicated to solar return flow only and not connected to the existing plumbing. Of course this only helps when the issue is somewhat oversized pumps, having too small of pump to manage efficient solar flow can still be a problem.

Ike

 

[jblizzle]

Re: Am spec'ing out my pool to PBers and want to option sola

My 1HP 2-speed runs my solar just fine. Mark uses a 1/2HP pump to run solar on a 2-story.

Just about any reasonable pump you get for the pool will run the solar just fine (maybe not optimal, but fine). If it is too strong, you can adjust how much water is diverted to the solar to lower the panel pressure.

How much pump you need really depends more on the details of the pool ... will you have a spa? waterfeature? etc? The bigger the pump, the more it costs upfront and the more it costs to run. Certainly get a 2-speed, although you may have rebates available for VS (there are smaller VS pumps that could work as well) ... we do not have any rebates down here.

 

[Isaac-1]

Re: Am spec'ing out my pool to PBers and want to option sola

Jason what you say about diverting flow away from the solar is only true if the source of the excess back pressure is not return lines to the pool. I am currently fighting that balance issue myself, installing larger eyeball fittings or alternative venturi fittings to reduce back pressure also also effects pool circulation and skimming.

 

[surferbum]

Re: Am spec'ing out my pool to PBers and want to option sola

As an aside, having talked to four PB in my area the subject of pump speed and HP comes up with every one. One says it must be variable-speed pump to conform to new AZ law. Another says the law calls out for multi-speed which can mean 2-speed. After reviewing articles on the 2012-law it seems unambiguously to mean 2 or more speeds. Don't know whether the pool builder pushing variable-speed was ignorant or greedy.

 

[jblizzle]

Re: Am spec'ing out my pool to PBers and want to option sola

Glad you researched that for yourself ... I think it actually states that anything over 1HP must be 2+ speeds. But below that could still be a single speed. {But don't quote me on that }