Hey there! I'm in Tucson, AZ, with the hot sun beating down on all the pool equipment. Having issues with the pipes that run the water up to the solar heater making extremely loud glugging sounds at night as though there are bubbles surfacing in them. Called out our pool tech today and he couldn't hear the sound and told me there was no possible way it was happening, so that was not helpful. 2 hours after the equipment shut off today, I can hear water running consistently through the pipes near the pump. I sent a video to him via text but I'm kind of tired of being told I just don't understand (he first decided to explain the timer to me, which I've known how to use for years..). What is going on here? I am certain there must be a leak somewhere. There's water coming out of the actuator valve, especially when it's cold outside or I run the pool overnight (to avoid said noise waking me up). The noise gets worse the longer the equipment is off. Would really appreciate any suggestions!
Solar and Actuator Valve Issues
- Thread starter qquiscula
- Start date
MSchutzer
Silver Supporter
If I were to guess I would say that your check valve is leaking allowing the water to back flow slowly (gurgling air though the filter as it does.
In almost all solar systems there is vacuum breaker in the system to allow the water to drain out of the panels when shut off.
When the pump is shut off you want all that water to run out of the solar pipes and flow to the pool return lines. There’s usually a check valve in the supply line after the pump and before the solar diverter valve. This check valve prevents the panels from draining back through the filter which would cause junk in the filter to flow backward into the pool.
I have a check valve in my system also, and at one point the seal on the flapper had a small split in it. This allowed a little bit of the water in the filter to back flow to the pool when the solar was off. At night I would hear occasional gulping and burping (sort of like a water cooler sound) as the pool equipment is outside a bedroom wall. As the water slowly leaks out of the filter back into the pool air burps through the pipes (due to the open vacuum breaker) and ends up in the top of the filter. When it does, it burps like a water cooler. This sounds like what you are hearing.
As I’ve heard that same noise on my system I would guess your check valve is leaking a little water backwards.
Can you post some pictures of the plumbing from the pump output to the filter, and then to your solar diverter valve. I can help you identify if you have a check valve in the system.
In almost all solar systems there is vacuum breaker in the system to allow the water to drain out of the panels when shut off.
When the pump is shut off you want all that water to run out of the solar pipes and flow to the pool return lines. There’s usually a check valve in the supply line after the pump and before the solar diverter valve. This check valve prevents the panels from draining back through the filter which would cause junk in the filter to flow backward into the pool.
I have a check valve in my system also, and at one point the seal on the flapper had a small split in it. This allowed a little bit of the water in the filter to back flow to the pool when the solar was off. At night I would hear occasional gulping and burping (sort of like a water cooler sound) as the pool equipment is outside a bedroom wall. As the water slowly leaks out of the filter back into the pool air burps through the pipes (due to the open vacuum breaker) and ends up in the top of the filter. When it does, it burps like a water cooler. This sounds like what you are hearing.
As I’ve heard that same noise on my system I would guess your check valve is leaking a little water backwards.
Can you post some pictures of the plumbing from the pump output to the filter, and then to your solar diverter valve. I can help you identify if you have a check valve in the system.
Last edited:
Thank you for the insight! Attaching some photos.. I don't think we have a check valve- in fact I think the tech that came out yesterday suggested installing one to fix the problem, but seemed to feel like that also was not likely to solve the problem. One of the photos is of the water coming out of the valve actuator. When I turn off the equipment after it's been running for a long time, I can hear a sound as though it's sucking in air.
MSchutzer
Silver Supporter
Is this a new problem or has your system always made this noise after the pump is off while the water is draining?
There’s usually a vacuum relief valve up at the panels to let the water drain out of the panels. Unless I’m missing something there’s nothing to prevent some of that water from flowing backwards through the filter regardless of which way the solar valve is set.
If there’s no vacuum valve then the panels form a closed loop and it could work without a check valve as long as there is no way for air to leak into the system. If air leaks in the weight of the water will cause it to drain back to the pool. But it’s really a bad design not to have a vacuum valve as the water stays up in the panels where it could potentially freeze.
If this is something that just started happening then it may be that it’s the leak in your solar control valve as if it’s leaking water it will also let air back into the system when the pump is off.
The burping you are hearing indicates that the water in the filter is slowing draining out, and as water drains out air gulps back into the filter from the outlet line (which is likely open to the air due to the vacuum breaker).
The right way to fix this is to add a check valve right after the pump output, it looks like you have a nice straight pipe section right before your temperature sensor where it could go.
Here’s a picture of my setup, in my case the check valve is a combo check valve and flow meter.
I hope this helps.
There’s usually a vacuum relief valve up at the panels to let the water drain out of the panels. Unless I’m missing something there’s nothing to prevent some of that water from flowing backwards through the filter regardless of which way the solar valve is set.
If there’s no vacuum valve then the panels form a closed loop and it could work without a check valve as long as there is no way for air to leak into the system. If air leaks in the weight of the water will cause it to drain back to the pool. But it’s really a bad design not to have a vacuum valve as the water stays up in the panels where it could potentially freeze.
If this is something that just started happening then it may be that it’s the leak in your solar control valve as if it’s leaking water it will also let air back into the system when the pump is off.
The burping you are hearing indicates that the water in the filter is slowing draining out, and as water drains out air gulps back into the filter from the outlet line (which is likely open to the air due to the vacuum breaker).
The right way to fix this is to add a check valve right after the pump output, it looks like you have a nice straight pipe section right before your temperature sensor where it could go.
Here’s a picture of my setup, in my case the check valve is a combo check valve and flow meter.
I hope this helps.
Thank you again! I'll look into getting the check valve installed. It's always made SOME noise but its gotten really loud the last two weeks. It definitely wasn't waking me up at night before.
MSchutzer
Silver Supporter
By the way your solar actuator valve that is leaking is easy to fix. There is one 3 to 4” O-ring on the valve lid, and a pair of O-rings in the area where the valve handle passes through the valve lid.
You can buy replacement O-ring kits for the valve and it only takes a Phillips screwdriver, a little silicon grease, and about 10 minutes to completely replace those O-rings.
You can buy replacement O-ring kits for the valve and it only takes a Phillips screwdriver, a little silicon grease, and about 10 minutes to completely replace those O-rings.
Thanks! A little update.. I sent videos of the noise and leak to the same tech, and he said "okay this makes sense, there must be a problem with the programming in the solar". That makes.. zero sense.. am I right? Especially as the programming has not changed in years. I'm really considering calling someone else at this point.
MSchutzer
Silver Supporter
I don't see how the programming of the valve is involved either.
Lets say the valve was in the solar on position (when the pump turns off), then the solar feed pipe would be connected to the output of your SWG. When the vacuum relief valve opens up the water in the solar feed pipe drains back though the SWG, filter, and pump to the pool. The water in the return solar pipe would drain back to the pool though the pool return line.
If the Solar valve is off with the pump off, then the solar feed pipe would be closed and a column of water would be sitting above the closed valve in the feed pipe. When the vacuum breaker valve opens up at the panels then the water in the panels drains back down the solar return pipe causing water to flow through the Tee junction with the returns on one side, and the output of the SWG on the other side. There's probably less restriction on the return side so more water will flow there, but there's nothing to prevent back flowing through SWG, filter, and pump while the panels are draining. Once the water column in the solar return pipe drains down to a level that is below the top of pipe in your SWG loop then all the remaining water will return via the pool returns.
But even when the system is off for a long time you have a filter that is full of water and the top of the filter is 3' or so above ground level. The SWG pipe loop on the filter output is above the top of the filter and since water doesn't flow uphill the filter will not drain out back through the output. So you have the weight of the water in the filter trying to seek its level, which is the pool level and it will drain back through the pump to the pool. As soon as it starts to drain back down the output side of the filter will be in vacuum. If the output side of the filter is full of water then you're fine and you have a closed loop of water. But there's likely a vacuum breaker on the panels that will let air into the system, and there's also the leaky O-rings on your Solar valve that will slowly let air in when the pump is off.
As the air is let into the piping on the outlet side of the filter the water in the filter slowly drains back into the pool via the pump, and as the water leaves the filter it will gulp air back in from the outlet side piping.
You can try and replace the O-rings in the valve as a first step and see if that helps, but I don't see how that will completely eliminate the back flow issue.
I still think the proper way to fix the back flow issue is to add a check valve in the pump outlet line. That will stop any back flow and filter draining regardless if the output side is open to the atmosphere when the vacuum relief valve is open.
Lets say the valve was in the solar on position (when the pump turns off), then the solar feed pipe would be connected to the output of your SWG. When the vacuum relief valve opens up the water in the solar feed pipe drains back though the SWG, filter, and pump to the pool. The water in the return solar pipe would drain back to the pool though the pool return line.
If the Solar valve is off with the pump off, then the solar feed pipe would be closed and a column of water would be sitting above the closed valve in the feed pipe. When the vacuum breaker valve opens up at the panels then the water in the panels drains back down the solar return pipe causing water to flow through the Tee junction with the returns on one side, and the output of the SWG on the other side. There's probably less restriction on the return side so more water will flow there, but there's nothing to prevent back flowing through SWG, filter, and pump while the panels are draining. Once the water column in the solar return pipe drains down to a level that is below the top of pipe in your SWG loop then all the remaining water will return via the pool returns.
But even when the system is off for a long time you have a filter that is full of water and the top of the filter is 3' or so above ground level. The SWG pipe loop on the filter output is above the top of the filter and since water doesn't flow uphill the filter will not drain out back through the output. So you have the weight of the water in the filter trying to seek its level, which is the pool level and it will drain back through the pump to the pool. As soon as it starts to drain back down the output side of the filter will be in vacuum. If the output side of the filter is full of water then you're fine and you have a closed loop of water. But there's likely a vacuum breaker on the panels that will let air into the system, and there's also the leaky O-rings on your Solar valve that will slowly let air in when the pump is off.
As the air is let into the piping on the outlet side of the filter the water in the filter slowly drains back into the pool via the pump, and as the water leaves the filter it will gulp air back in from the outlet side piping.
You can try and replace the O-rings in the valve as a first step and see if that helps, but I don't see how that will completely eliminate the back flow issue.
I still think the proper way to fix the back flow issue is to add a check valve in the pump outlet line. That will stop any back flow and filter draining regardless if the output side is open to the atmosphere when the vacuum relief valve is open.