Building Materials for Manifold

[bbaper]

I have 5 solar panels that I'm planning on running in parallel. In wondering materials people have used to build their manifold to supply water to their panels.

My panels are using 1/2" polyethylene.
I have 1.5" PVC coming from my pump.

In the Rimstar photo it looks like they are using MDPE pipe with unions on a tee? Don't know where I would get either in Canada.

The connectors for PVC are very limited. The pool supply store said the could possibly order a 1.5" to 1/2" PVC tee. Didn't want to even ask the price.

I found polyethylene tees 1.5" to 1/2", but I would have to use clamps.
TIA

Walter

[Mike90250]

Have you looked into CPVC pipe & fittings ?

[bbaper]

Have you looked into CPVC pipe & fittings ?

Thanks for the suggestion Mike. I looked on homedepot.com, and the CPVC 1.5 x 1.5 x .5 tees are $10... each.

Hoping for something cheaper.

I was wondering what materials people had been making their Manifolds of.

[russ]

Thanks for the suggestion Mike. I looked on homedepot.com, and the CPVC 1.5 x 1.5 x .5 tees are $10... each.

Hoping for something cheaper.

I was wondering what materials people had been making their Manifolds of.

That seems horribly expensive - look for other web sites - With solar panels you can get excessively high temps for plastic - that is the reason copper is used.

On Rimstar they are working with the black plastic coils? Much lower temps involved.

[skeeter_ca]

So are you saying you cannot get PVC at the local hardware stores or big box stores in Canada? PVC is what is used most the time in solar systems. If you can I would go with 2" just to help reduce friction loss on long runs. A 2" tee from Home Depot runs about $2.25. You could probably work up an order and have it shipped to you cheaper than a pool store would sell it to you. After assembly paint it black to protect it from UV rays.

You would not be seeing temps any higher with commercial panels as opposed to properly designed DIY coil panels. PVC can easily handle the temps and pressures associated with solar pool systems. Of course every effort should be made to have the lowest operating pressure possible on the solar system whether it be commercial or DIY panels.

skeeter

[russ]

You would not be seeing temps any higher with commercial panels as opposed to properly designed DIY coil panels. In stagnated condition that can be well over 100°C (212°F)

PVC can easily handle the temps and pressures associated with solar pool systems. Yes and no - this is DIY

skeeter

Comments in bold in the text

[bbaper]

So are you saying you cannot get PVC at the local hardware stores or big box stores in Canada? PVC is what is used most the time in solar systems. If you can I would go with 2" just to help reduce friction loss on long runs. A 2" tee from Home Depot runs about $2.25. You could probably work up an order and have it shipped to you cheaper than a pool store would sell it to you. After assembly paint it black to protect it from UV rays.

You would not be seeing temps any higher with commercial panels as opposed to properly designed DIY coil panels. PVC can easily handle the temps and pressures associated with solar pool systems. Of course every effort should be made to have the lowest operating pressure possible on the solar system whether it be commercial or DIY panels.

skeeter

Here it seems the Home Depot leave it to the Pool Stores to carry the PVC. Lowes has opened up here recently, and they carry a limited variety of PVC fittings. I did find a local store that carries all kinds of PVC fittings. a 1.5 x 1.5 x .5 tee is just under $5. Since I need 10 that's still $50. Plus the PVC pipe. I looked a site in the US that would ship to Canada. They doubled the price with shipping charges.

This is a DYI project. I think I will take your advice about using the PVC and painting it black.

Thanks for the input Skeeter.

[russ]

Here it seems the Home Depot leave it to the Pool Stores to carry the PVC. Lowes has opened up here recently, and they carry a limited variety of PVC fittings. I did find a local store that carries all kinds of PVC fittings. a 1.5 x 1.5 x .5 tee is just under $5. Since I need 10 that's still $50. Plus the PVC pipe. I looked a site in the US that would ship to Canada. They doubled the price with shipping charges.

This is a DYI project. I think I will take your advice about using the PVC and painting it black.

Thanks for the input Skeeter.

There is a big difference in ratings as regards service temperature for the PVC vs CPVC - check those temps first - the advice as given is WRONG without warning you.

If you look around someone should be selling the pipe that are not thieves.

[russ]

For solar panels I used copper to the heat exchanger in the tank as the temp was potentially too high for any type of plastic pipe.

For a RimStar type plastic coil heater this is not a concern.

[skeeter_ca]

All solar systems should have a vacuum break installed on the system. If the system is shut down during the daytime the water should all drain back out of the system. This prevents a stagnate water situation and intense heat build up. When the water is flowing through the panels the temps are alot lower and is not a concern. All solar pool heaters should have vacuum breaks installed in the system for this very reason. Even the the commercial system do not allow stagnate conditions in the panel while the sun is shining on them because the intense heat is not a good thing.

All the systems i have seen or read about all use standard PVC plumbing. CPVC is not the standard. The only time i have heard of using CPVC is when PVC is not available or the DIY'er already had it on hand from another project. What kind of pipe is used on your pool now. PVC. Can you use CPVC, of course but it is over kill. If you had a heater, gas or electric, it would be connected with PVC. Here in California PVC is used almost exclusively for solar system plumbing. And the last time i checked it gets pretty hot here, 107 today.

Also look up irrigation stores that sell to landscapers. They should have a good selection of pipe and fittings at a reasonable price.

As for pressure in a solar system, you should not be seeing anything above 30psi. If you are you should have a good look at your design to see where all the back pressure is coming from and redesign the system properly. Alot of good systems run pressures alot lower. Friction loss is one big back pressure cause which is why i recommended the 2" pipe if possible. Also your coils need to be long enough to absorb the heat but not so long to cause to much back pressure. Either way PVC and irrigation plumbing can easily handle those pressures under normal operating temperatures.

skeeter

[skeeter_ca]

Solar panels for heat exchangers, like for storing hot water for later use, is an entirely different animal than solar panel collectors to heat a pool. They both use the sun but for different outcomes.

Solar pool collectors use the water in the pool to circulate through the collector to gain heat and return it back to the pool immediately. Water is constantly flowing the entire time unless the pump is shut down and then the water drains out of the collector so it is empty. Pool water also has some nice chemicals in it which is not at all good for copper to be exposed to.

Solar panels for heat exchangers keep the water in the collector even when there is no circulation which helps to add even more heat to the water. Hence the need for high temp application like copper.

skeeter

[russ]

Solar panels for heat exchangers, like for storing hot water for later use, is an entirely different animal than solar panel collectors to heat a pool. They both use the sun but for different outcomes.

Skeeter - this is a DIY system - could be most anything.

CPVC is commonly used throughout the developed and even developing world where water up to say 90° C (200°F for backwards groups). PVC is good up to about 50°C (about 120°F)

Stagnating water temps in any kind of panel can go well above boiling - I think everyone is well aware of the differences i=between pool and dhw systems - but this is DIY and the OP talks of panels.

The siphon break is used sometimes and sometimes not.

[skeeter_ca]

Russ - Thats true it could be for just about any kind of application.

I guess i jumped to conclusions when he was asking a pool supply store for PVC fittings. So i guess to find out just what this is for perhaps we should ask the OP.

bbaper - What is this panel going to be used on because as Russ has pointed out it does make a difference?

skeeter