Sta Rite Pool Heater
- Thread starter CanadaDave
- Start date
So - control board received... though an interesting thing happened.
My wife wanted to use the spa, so I turned the heater on (have not yet replaced the board). Ran for around an hour, then the heater gave the clunking noise again and died out, AGS light. I thought this was meaningful as I didn't think the clunking noise was still happening, but it is. I happened to be looking at the outside display panel when that happened.. water temp of the spa was around 102, and it didn't rise rapidly or anything during the clunking.
I cut power to the heater, waited a few minutes, then gave it power again. It fired up and ran for a few minutes, then tripped back off. Stupidly, I was in the house when that happened and I didn't hear if there was a noise, and I REALLY stupidly didn't flip it upside down to see if it was AGS before cutting power.
I cut power to the heater again and tried flipping it back within 10 seconds, but this time it did not fire - AFS light (not AGS). I cut power, waited 5 minutes or so, and powered it on again, and it fired up properly. It was pretty late by this time though, so I didn't see how long it would go.
So, a few (new?) learnings:
1) When heater fails, it still clunks (or bangs). It was more "bang, bang, bang" with about a half second between the bangs this time instead of in the video I posted that was a little more of a grinding noise. Failure light is AGS.
2) If I let the heater sit for a few minutes then apply power again, it fires up, but it will run for a much shorter period than before. Unfortunately, no confirmation as to if the failure light is AGS or if it bangs on failure.
3) Once it fails, if I cut power and then re-apply power within a few seconds, the heater refuses to fire with AFS (not AGS).
Given the above, I had a couple of thoughts that may or may not be correct, just kind of based on my having read a ton of posts here:
1) With the heater still banging, we're probably not looking at an electronic type failure, but rather a mechanical failure. That means we're probably not looking at a control board or Fenwal, since there's no real scenario where an electronic part can make the heater do that. Is that a fair assessment?
2) Since we're back to banging, the likely culprits are either that valve (maybe the spring is too weak? it looked intact) or that there's some sort of build-up inside the heating tube.
What do you think, guys? Am I thinking along the right lines, or should I still swap out the control board, just to see? I can return the board even if it has been opened (it hasn't yet) as long as it's still in pristine condition, but if the banging removes the control board as a failure option, then I'd just as soon return it unopened to save the seller some headaches.
My wife wanted to use the spa, so I turned the heater on (have not yet replaced the board). Ran for around an hour, then the heater gave the clunking noise again and died out, AGS light. I thought this was meaningful as I didn't think the clunking noise was still happening, but it is. I happened to be looking at the outside display panel when that happened.. water temp of the spa was around 102, and it didn't rise rapidly or anything during the clunking.
I cut power to the heater, waited a few minutes, then gave it power again. It fired up and ran for a few minutes, then tripped back off. Stupidly, I was in the house when that happened and I didn't hear if there was a noise, and I REALLY stupidly didn't flip it upside down to see if it was AGS before cutting power.
I cut power to the heater again and tried flipping it back within 10 seconds, but this time it did not fire - AFS light (not AGS). I cut power, waited 5 minutes or so, and powered it on again, and it fired up properly. It was pretty late by this time though, so I didn't see how long it would go.
So, a few (new?) learnings:
1) When heater fails, it still clunks (or bangs). It was more "bang, bang, bang" with about a half second between the bangs this time instead of in the video I posted that was a little more of a grinding noise. Failure light is AGS.
2) If I let the heater sit for a few minutes then apply power again, it fires up, but it will run for a much shorter period than before. Unfortunately, no confirmation as to if the failure light is AGS or if it bangs on failure.
3) Once it fails, if I cut power and then re-apply power within a few seconds, the heater refuses to fire with AFS (not AGS).
Given the above, I had a couple of thoughts that may or may not be correct, just kind of based on my having read a ton of posts here:
1) With the heater still banging, we're probably not looking at an electronic type failure, but rather a mechanical failure. That means we're probably not looking at a control board or Fenwal, since there's no real scenario where an electronic part can make the heater do that. Is that a fair assessment?
2) Since we're back to banging, the likely culprits are either that valve (maybe the spring is too weak? it looked intact) or that there's some sort of build-up inside the heating tube.
What do you think, guys? Am I thinking along the right lines, or should I still swap out the control board, just to see? I can return the board even if it has been opened (it hasn't yet) as long as it's still in pristine condition, but if the banging removes the control board as a failure option, then I'd just as soon return it unopened to save the seller some headaches.
So when you first took the manifold off, how did the thermo regulator look? I looked back on the posts of this and I didn't see anything, could have missed it though, where you talked about it. Also, when you cleaned it out, did you by chance try to spray any water into the tubes to see how it came out the other side? I'm wondering if you have a clogged tube or two. As for the bypass, again, your picture shows it's intact so I wouldn't think that would cause the issue. I've never encountered a "weak" spring, just a broken plastic piece.
The control board wouldn't be causing the sound you are hearing. That is a water flow issue.
The control board wouldn't be causing the sound you are hearing. That is a water flow issue.
Thanks a lot, Paul - I appreciate the reply!
When I took the manifold off, the thermo regulator had that filter tie all wrapped around it. I took that off, but it seemed to work just fine and I couldn't see any breaks or anything. In addition to the two pictures above, I have these two that shows the bottom and what the spring looks like in "resting" position, which seems to me to be intact:
...I didn't squirt any water in the individual holes, no, because at the time I thought it was pointless because water is always flowing through the heater. However, now that I think about it... if one or two tubes are clogged, then water would still flow properly, just through the other tubes! Interesting. I'll take that manifold cover off and give that a shot. My wife's dragging me to a formal thing this afternoon, though, so it'll probably be tomorrow, rats.
Is there a particular technique for cleaning out the individual tubes, or just squirt as high a pressure as possible through each one and hope for the best?
When I took the manifold off, the thermo regulator had that filter tie all wrapped around it. I took that off, but it seemed to work just fine and I couldn't see any breaks or anything. In addition to the two pictures above, I have these two that shows the bottom and what the spring looks like in "resting" position, which seems to me to be intact:
...I didn't squirt any water in the individual holes, no, because at the time I thought it was pointless because water is always flowing through the heater. However, now that I think about it... if one or two tubes are clogged, then water would still flow properly, just through the other tubes! Interesting. I'll take that manifold cover off and give that a shot. My wife's dragging me to a formal thing this afternoon, though, so it'll probably be tomorrow, rats.
Is there a particular technique for cleaning out the individual tubes, or just squirt as high a pressure as possible through each one and hope for the best?
OH - sorry - you were asking about the regulator, not the bypass. It looked good, but it had that wrap tied around it so it wasn't moving freely. I did replace the regulator and spring 2 months ago... when I moved in, there was no regulator in there at all!
The bypass likes like it should.
If several of the tubes are partially clogged, it would make that racket also.
If several of the tubes are partially clogged, it would make that racket also.
Today's the day - I'll be taking the bugger apart after work.
Is there a "proper" technique for cleaning them out? Should I try and get a small brush (stiff wire / soft wire / etc) and use that to clean the tubes, or am I best off just using a garden hose with a spray nozzle?
Last thing in the world I want to do is damage them.
dave
Pool Clown
In The Industry
Your electronics appear to be working. The banging (overheat condition), and subsequent shut down is the system working properly. I wouldn't take the electronics out of their packaging, it is your only hope to get a refund.
Do you Check the Ph often? And does it run high? (scaling of the tubes)
Could be more of the cartridge wrap you found only in the tubes this time.
May be therm by-pass, but didn't you change that already?
Dirty filter or just too low of flow through the heater (water is gaining/absorbing too much heat).
Does the heater have an external by-pass that is open? even a little?
Sooting? I think we may have gone over that already...
Bottom line is that it is banging (water is boiling) before it shuts down , and that is, for what ever reason, too much heat (ags).
Do you Check the Ph often? And does it run high? (scaling of the tubes)
Could be more of the cartridge wrap you found only in the tubes this time.
May be therm by-pass, but didn't you change that already?
Dirty filter or just too low of flow through the heater (water is gaining/absorbing too much heat).
Does the heater have an external by-pass that is open? even a little?
Sooting? I think we may have gone over that already...
Bottom line is that it is banging (water is boiling) before it shuts down , and that is, for what ever reason, too much heat (ags).
Hey everyone!
Just checking back in... at long last, I had the opportunity to take the thing apart. It's cramped working in there, so it takes a fair bit of time.
When I squirted water into the nozzles, there wasn't much of anything in there, but there may have been some sediment in the two middle tubes that came out with the initial blast. Whatever - when I was doing it, I had the jet nozzle on flush against one side of the tube, and water was running freely out the other side of the tube without back pressure, so I think they should be considered clear. Nothing like the filter wraps or anything.
I've got the system back together now with the heater on, so we'll see how things run. I was really hoping for a TON of stuff to come out so I'd feel better about having found the cause, but there was no "angels choir singing" moment. Like I said, there may have been a little bit in those middle tubes. Does it take much to restrict flow to the point where water will boil?
A couple of answers to the above: There isn't any bypass in the system - the heater is fully in line, no ability to divert water from the heater. The thermal bypass is indeed new, and I can't think of how I could mess up installing that - though I do a lot of brain-dead things, so I suppose it's possible!
I'm pretty good with monitoring the water, I think (though I think everyone probably says that). I take my water to the pool place for free testing every 2 weeks, and I use the strips in the meantime every few days, so things shouldn't be too far out of whack at any time. I got them to test yesterday, and all levels were within recommended spec. Ph in particular was 7.3. There was no scaling found in either the manifold when I took it apart or the tubes when I blasted water in there, so there doesn't appear to be anything chronic.
I'll let 'er rip for a few hours, and that should tell the tale as to whether the heater is happy now or not!
Whether the fix is there or not, I really want to thank both of you - PS0303 and Pool Clown - in particular for your help on this stuff. I'm working hard to keep an old pool up and running for my kids and don't have a lot of money to spend, and your advice is really invaluable in making that happen. Seriously, thanks a ton to you both.
Just checking back in... at long last, I had the opportunity to take the thing apart. It's cramped working in there, so it takes a fair bit of time.
When I squirted water into the nozzles, there wasn't much of anything in there, but there may have been some sediment in the two middle tubes that came out with the initial blast. Whatever - when I was doing it, I had the jet nozzle on flush against one side of the tube, and water was running freely out the other side of the tube without back pressure, so I think they should be considered clear. Nothing like the filter wraps or anything.
I've got the system back together now with the heater on, so we'll see how things run. I was really hoping for a TON of stuff to come out so I'd feel better about having found the cause, but there was no "angels choir singing" moment. Like I said, there may have been a little bit in those middle tubes. Does it take much to restrict flow to the point where water will boil?
A couple of answers to the above: There isn't any bypass in the system - the heater is fully in line, no ability to divert water from the heater. The thermal bypass is indeed new, and I can't think of how I could mess up installing that - though I do a lot of brain-dead things, so I suppose it's possible!
I'm pretty good with monitoring the water, I think (though I think everyone probably says that). I take my water to the pool place for free testing every 2 weeks, and I use the strips in the meantime every few days, so things shouldn't be too far out of whack at any time. I got them to test yesterday, and all levels were within recommended spec. Ph in particular was 7.3. There was no scaling found in either the manifold when I took it apart or the tubes when I blasted water in there, so there doesn't appear to be anything chronic.
I'll let 'er rip for a few hours, and that should tell the tale as to whether the heater is happy now or not!
Whether the fix is there or not, I really want to thank both of you - PS0303 and Pool Clown - in particular for your help on this stuff. I'm working hard to keep an old pool up and running for my kids and don't have a lot of money to spend, and your advice is really invaluable in making that happen. Seriously, thanks a ton to you both.
Nope, darn. She just died out again after about 45 minutes. Noise still... some chunking/banging after a while, and then "Service Heater" with AGS light underneath. Hm.
So, let me recap what I've done so far, and what I have not done. Maybe there's something that I'm missing, here:
- AGS, HLS, Thermistor and Thermal regulator have been replaced and are new. Edit: For giggles, I swapped the new water pressure switch back in with the old one this morning just to see if it made a difference, but no change.
- Manifold has been taken off and checked for debris. The cartridge wrap was found in there the first time and removed. No debris found the second time it was removed.
- Manifold Bypass valve removed and checked for damage and operation. This has not been replaced.
- Squirted water through each of the tubes in the heat exchanger. Water flow seems to be fine, in that I get a steady stream of water in one end and out the other without a bunch of back pressure or anything. Possible that a small amount of debris came out of a couple of tubes, but nothing of note.
- Heater is in-line with the rest of the system. No bypass exists. Water flows from the pump to the filter, then directly through the heater and then to the rest of the system (salt cell, pool, etc).
- I've cleaned the pool filters regularly (and did that yesterday morning, in fact, before this latest attempt).
I have not actually replaced the manifold bypass valve, which I can certainly do. I did assemble the thermal regulator myself (spring, clip and thermostat) - is it possible that I've done that incorrectly? I could potentially try just the regulator and spring without the clip, for example... it's worth noting, however, that when I bought the house, there was no regulator in there at all and the symptoms were identical.
I still have the control board in its original packaging if that's worth try.
Symptom is that the heater will run for a while (generally 45 minutes to 2 hours), then make a chunking/banging noise and fail with AGS light on. If I wait a few minutes and re-apply power to the heater, it will turn back on, but then only run for a few minutes before failing.
So, let me recap what I've done so far, and what I have not done. Maybe there's something that I'm missing, here:
- AGS, HLS, Thermistor and Thermal regulator have been replaced and are new. Edit: For giggles, I swapped the new water pressure switch back in with the old one this morning just to see if it made a difference, but no change.
- Manifold has been taken off and checked for debris. The cartridge wrap was found in there the first time and removed. No debris found the second time it was removed.
- Manifold Bypass valve removed and checked for damage and operation. This has not been replaced.
- Squirted water through each of the tubes in the heat exchanger. Water flow seems to be fine, in that I get a steady stream of water in one end and out the other without a bunch of back pressure or anything. Possible that a small amount of debris came out of a couple of tubes, but nothing of note.
- Heater is in-line with the rest of the system. No bypass exists. Water flows from the pump to the filter, then directly through the heater and then to the rest of the system (salt cell, pool, etc).
- I've cleaned the pool filters regularly (and did that yesterday morning, in fact, before this latest attempt).
I have not actually replaced the manifold bypass valve, which I can certainly do. I did assemble the thermal regulator myself (spring, clip and thermostat) - is it possible that I've done that incorrectly? I could potentially try just the regulator and spring without the clip, for example... it's worth noting, however, that when I bought the house, there was no regulator in there at all and the symptoms were identical.
I still have the control board in its original packaging if that's worth try.
Symptom is that the heater will run for a while (generally 45 minutes to 2 hours), then make a chunking/banging noise and fail with AGS light on. If I wait a few minutes and re-apply power to the heater, it will turn back on, but then only run for a few minutes before failing.
WOW....
You have pretty much done everything to this heater. I guess if you want to try replacing the bypass and see what if anything that does. It just looks like it's in good shape and not the issue.
The board wouldn't be the issue now. The clunking sounds, I watched your video several times, is a typical sound you get when the bypass is broken or poor water flow.
You have pretty much done everything to this heater. I guess if you want to try replacing the bypass and see what if anything that does. It just looks like it's in good shape and not the issue.
The board wouldn't be the issue now. The clunking sounds, I watched your video several times, is a typical sound you get when the bypass is broken or poor water flow.
Pool Clown
In The Industry
Nope... the pump is a 1.5hp single speed Sta-Rite..
The system runs at 21-22 PSI when the filters are clean, and around 25 when the filter is really dirty... except for when I have the system set 100% to the spa, and then it runs at around 30 PSI, as there's only one outlet for water in the spa, where there are 5 or 6 (can't remember) for the pool so there's correspondingly more back pressure getting the water pushed out.
How much flow is actually necessary for this not to happen? I genuinely can't imagine that a droplet of water is spending more than a second in the tube given how much water is gushing through the system. Is it somehow possible that the flame itself is somehow way too high for the heater, and it's superheating the water in the amount of time it has? It's a big beast - 400,000 BTU - so maybe if the flame is way too high or something, it's making it too hot?
I'll grab a bypass and put that in just for completeness, I suppose. It's not a wildly expensive part, and it's about the last thing that I can imagine that it could potentially be.
I suppose there's a possibility that there's a supremely encrusted chunk of (something) in the far back end of one of the heat exchanger tubes that I would need some kind of chemical cleaner to get out of there. Does such a thing exist, where I can spray it in there, let it sit for a few seconds and then flush it out with water?
Beyond all of these things...... a partial plug in the pool lines themselves?! I honestly don't know. I'm kind of at a loss...
dave
The system runs at 21-22 PSI when the filters are clean, and around 25 when the filter is really dirty... except for when I have the system set 100% to the spa, and then it runs at around 30 PSI, as there's only one outlet for water in the spa, where there are 5 or 6 (can't remember) for the pool so there's correspondingly more back pressure getting the water pushed out.
How much flow is actually necessary for this not to happen? I genuinely can't imagine that a droplet of water is spending more than a second in the tube given how much water is gushing through the system. Is it somehow possible that the flame itself is somehow way too high for the heater, and it's superheating the water in the amount of time it has? It's a big beast - 400,000 BTU - so maybe if the flame is way too high or something, it's making it too hot?
I'll grab a bypass and put that in just for completeness, I suppose. It's not a wildly expensive part, and it's about the last thing that I can imagine that it could potentially be.
I suppose there's a possibility that there's a supremely encrusted chunk of (something) in the far back end of one of the heat exchanger tubes that I would need some kind of chemical cleaner to get out of there. Does such a thing exist, where I can spray it in there, let it sit for a few seconds and then flush it out with water?
Beyond all of these things...... a partial plug in the pool lines themselves?! I honestly don't know. I'm kind of at a loss...
dave
Just a quick update: The bypass has been ordered and will arrive in a few days. My local dealer doesn't stock it and wanted $74 (!) plus 2 weeks to get it in, so Amazon got the business for $30 USD and 3 days shipping. Hate like heck to not support local businesses where I can, but the local monopoly on Pentair/Sta Rite is a little parasitic.
Anyway, rant over..
Just further to my question above. When I go in and replace the bypass, I want to take another run at cleaning those tubes out. Is there a spray I can use that will loosen the deposits that I might have, or similar? I *really* don't want to do something that will damage the copper, but I want to make absolutely sure that those tubes are 100% clear to rule anything out. It seemed like water flow was fine, honestly, but since I'll be in there anyway, it's worth a shot...
- - - Updated - - -
And also - is it possible that the flame is somehow too high, per above, so it's somehow heating the exchanger up too much? Is that even a thing with pool heaters?
Anyway, rant over..
Just further to my question above. When I go in and replace the bypass, I want to take another run at cleaning those tubes out. Is there a spray I can use that will loosen the deposits that I might have, or similar? I *really* don't want to do something that will damage the copper, but I want to make absolutely sure that those tubes are 100% clear to rule anything out. It seemed like water flow was fine, honestly, but since I'll be in there anyway, it's worth a shot...
- - - Updated - - -
And also - is it possible that the flame is somehow too high, per above, so it's somehow heating the exchanger up too much? Is that even a thing with pool heaters?
I wouldn't want to use any chemical to clean the tubes if that is what you were thinking. I'm not even aware of any type of bendable cleaning brush you could use. Unless there is something in the AC arena.
You would need a manometer to check gas pressure to see if it's too high causing a higher/hotter flame.
You would need a manometer to check gas pressure to see if it's too high causing a higher/hotter flame.
Just a quick update: I've ordered the manifold bypass as well as two really neat brushes that look like they will do a great job. They're meant for cleaning aquarium pipes, and they have springs on the end instead of hard steel. I ordered one with stiff bristles and one with soft bristles, and I'll take some pictures and show everyone. They were super-cheap, but unfortunately come on the slow boat from China, so it'll take a couple of weeks. I'll pass those through, replace the manifold bypass, and post back once that's all done. It'll be a quiet couple of weeks, though.
Once again, I wanted to thank everyone for their patience and help on this topic, especially PS0303 and Pool Clown. You folks are volunteering a lot of your time helping out people like me who could otherwise be taken for a pretty nasty ride (or stumble around blindly messing things up), and I, for one, really appreciate it. Thank you!!
Once again, I wanted to thank everyone for their patience and help on this topic, especially PS0303 and Pool Clown. You folks are volunteering a lot of your time helping out people like me who could otherwise be taken for a pretty nasty ride (or stumble around blindly messing things up), and I, for one, really appreciate it. Thank you!!
f3justusc
Well-known member
I am still following your thread. I applaud your perseverance and I am waiting to cheer when you tell us it is fixed!
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Hey - thank you as well, f3justusc - you saved me $200 with that "return to Amazon" idea! Without that, I'd have replaced the control board needlessly.
f3justusc
Well-known member
Awesome! I wondered if that was where you got it! Amazon is pretty darn good for most things!!