Possible solar bypas valve problem

[allenV]

Hi There,
I am fairly new to pools as I have only been maintaining one for about 7 months.

I have a solar system that does a great job heating up the pool. I've had to 'bypass' the solar system b/c the pool was getting too hot. I also bypass it when I run my polaris vacuum as I get air in the lines when I use the pump with the solar system in switched on. (different problem)

I have a single manual valve that switches between "Solar" and "Bypass". When the solar is bypassed I seem to get a lot of water creeping up the return pipe of the solar system to the roof.
When I took over the pool from the pool guys I was told by them to leave the drain spigot, on the solar return pipe from the roof, open. This results in a steady drip of about 8-10 gallons of pool water for an 8 hour pump cycle. This does not make sense to me. I closed the spigot and now when the pump shuts off there is a shuttering of the pipes as that water comes back down the pipe and I assume forces it's way through(?) the bypass valve and back into the pool.

Does this make sense and is it normal or do I have a partial leak in the solar/Bypass valve?

Any thoughts and comments would be appreciated.

Allen

 

[mas985]

It is quite common for both check valves and solar valves to leak a small amount of water (when off) which can fill the pipes even when solar is off. It is not ideal but nothing to get overly concerned about either.

Where are you located?

What is the filter pressure when solar is bypassed?

How high are the panels relative to the pump?

 

[allenV]

Re: Possible solar bypass valve problem

Hi Mark
I just down the road in San Jose.
The current filter pressure in bypass mode is 12, 17 with the solar engaged.
(10/15 just after cleaning)
The panels are on top of a two story house, say about 30ft.

Is it acceptable to keep the drain spigot closed, so I do not lose ~ 8 gallons a day?

I read on another thread that someone was leaving the bypass valve partially open, 90% solar/10% bypass.
Is that a more sophisticated valve than what looks to be a simple two position valve in my system?

Thanks,
Allen

 

[jblizzle]

I must be lucky that my valves do not leak. For a while I have my 3-way set with solar off and a check valve on the solar return, but the pipes heading up the house were cut about 4' off the ground ... never had any water come out.

Can you post a picture of your plumbing setup? That may help offer solutions. I would not think you should be getting water all the way up on the roof when the valves are closed.

You only need to partially open the bypass if your pump is supplying too much water to the panels.

BTW, we recommend cleaning the filter when the pressure rises 20-25% over the clean pressure ... looks like you are about there.

 

[mas985]

When the valves are new, they usually seal pretty well but as check valves age, they tend not to seal as well and some water may get by. But not in every case. However, if they do leak, the pressure created by the pump will fill the pipe to head level of the pressure even if the leak is very small. So in this case, the pipe would fill to at most 27' which is slightly below panel height.

I wouldn't be too concerned with it and it shouldn't cause any issues in your location. Also, I would keep the host bib closed and there really shouldn't be a reason to leave it open.

 

[allenV]

Thanks Mark and Jason for the informative reply's.
I seem to need to add enough water as it is and I am now comfortable to add about 50 gallons less each week (by closing the drain valve). My biggest concern was potential damage to the solar panels.

btw, I am planning to make time to clean the cartridges this weekend. I am learning as I go and I just won a battle with black algae and those filter cartridges earned their keep over the last few weeks.
I have attached pics of the plumbing to show how simple a system it is.

I still need to understand why the booster pump for the Polaris 280 won't prime due to air in the line when the solar panels are engaged. Perhaps I will start another topic and tap into this sites expertise!
Thanks again,
Allen

 

[mas985]

Why would the panels be damaged?

Is the polaris plumbed after the solar return? It should be plumbed immediately after the filter before the solar supply line.

 

[allenV]

Re: Possible solar bypass valve problem

Hi Mark,
By your response I should not concern myself if the solar system is half full of pool water.

I inherited the Booster Pump pluming , which is shown in the last pic on the previous post. The black hose going to the pump is indeed after the solar system, right before the water returns to the pool. The white hose coming out of the pump goes to a dedicated return line to the pool. Plumbing option 3 in this pic.

The thing is, I had no problems for most of spring using solar and vacuum together. One day lots of air in all return lines to the pool. I found no leaks in the suction side, no air in the main pump basket. Air could be seen in the visible eye joint in the return line from the solar. Shortly after this inefficient operation the the booster pump would cease to prime and I could no longer use the vacuum with the solar engaged.

Is their a valve located at the highest point of the solar system that may be partially opening letting air into the system? I think there has to be one there or the system would not drain when the pumps are turned off.

Just learning.
Allen

 

[jblizzle]

Fix your image like I did in the other post.

There is usually a VRV (vacuum release valve) that is often at the top of the panels. If your pump is not getting enough pressure to the top, then it may not close all the way and allow air in.

 

[allenV]

Thanks Jason, I think I got the image posting right now.
Aleln

 

[mas985]

The problem is where your booster is plumbed into the system. When solar is turned on, air will be flushed out of the panels and directed toward the booster suction port so the booster will suck air until the panels are primed. However, as JB points out, if the VRV is not closed all the way, this will continue and the booster will never prime. So is the booster never priming or just taking a long time to prime? Either way it is going to be a problem for the booster and it really should be moved.

 

[allenV]

Thanks guys.
From your advise it sounds like a have a re-plumb job to do this winter.
I may have an older valve that may not seal altogether like it used to but that is not a real concern.
Pressure may be the factor in the VRV not closing or staying closed when the booster is turned on and not a bad VRV.

I appreciate the assistance. Thanks
Allen