Hey guys, I posted late in 2021 about issues with my cranky old used AquaTherm stove / system, but I think those are mostly resolved now. However, I'm still not getting heat into my in-floor piping. I have hot water going through the mixing valve and into the pump (which is very hot to the touch), but then it cools quickly after that and any heat is basically gone by the time it turns downward to the left of the pump. This is a new system (installed in November 2021), but it only worked for the first couple days and then stopped. Could it be that the pump is shot? The system is showing pressure, but it's not enough to push the water through, apparently. I'd happily buy a new pump if that was the source of the problem, but I'd hate to spend the money if that's not it. (BTW - Please feel free to talk to me like a three-year-old. I wish I knew more about this system, but I'm largely clueless about what is taking place here.) Thanks!
![[Hearth.com] Troubleshooting In Floor Heat](https://www.hearth.com/talk/attachments/in-floor-boiler-1-webp.292330/ "[Hearth.com] Troubleshooting In Floor Heat")
Troubleshooting In Floor Heat
- Thread starter SplittingLogs
- Start date
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My question is why is the valve above your mixing valve that conects the red pex with the blue pex open?
Good question. I don't know the answer. Should I try closing that valve to see if it makes a difference with the floor?
Just a follow up. That definitely worked! Within a few minutes the manifold began heating up. Unfortunately there were unintended consequences. The pressure almost immediately dropped to virtually zero, the big red pex pipe eventually cooled off, and the system boiled over out at the furnace. My hypothesis is that the pipes in the basement are frozen after not having much water go through them this winter, which backed things up and caused issues in the rest of the system. Of course I may be way off on that too. For the moment I've opened that valve back up so I can at least warm the house through the plenum... assuming it will go back to the way it was. Thanks!
maple1
Minister of Fire
Could be air locked, hence the drop to zero. I see one hose bib to bleed with. And a hose above that. Should be able to hook that up to house feed and force water through the loops?
Hey guys, Thanks for all of your input! Yeah, I'm not sure what I was thinking when I said the pipes were frozen. Even with it getting stupid-cold up here in northern Wisconsin, that's obviously not the case (but does speak to my general ignorance). If it is an airlock (which definitely makes sense), could someone walk me through how to push the air out, or test for that? I see Maple's suggestion above about the hose and the bib, but I'm not sure what exactly to do there.
BTW - The installer keeps blaming the floor issue on the filter in the mixing valve getting plugged with crap. I acknowledge that there could be some junk in there. We have very hard water, and we're heating with an old, second-hand AquaTherm that may have some stuff floating in it from years of use. However, I'm not sure that this is the problem because a) he's already cleaned out the filter and it didn't make a difference, and b) the hot water is getting through the mixing valve and to the pump, but not much farther than that. Any chance that could actually be the culprit?
Thanks guys! I'm trying to learn. I appreciate your help, advice and insight!
BTW - The installer keeps blaming the floor issue on the filter in the mixing valve getting plugged with crap. I acknowledge that there could be some junk in there. We have very hard water, and we're heating with an old, second-hand AquaTherm that may have some stuff floating in it from years of use. However, I'm not sure that this is the problem because a) he's already cleaned out the filter and it didn't make a difference, and b) the hot water is getting through the mixing valve and to the pump, but not much farther than that. Any chance that could actually be the culprit?
Thanks guys! I'm trying to learn. I appreciate your help, advice and insight!
Splitting Logs With floor heat it pretty simple you need hot water and you need flow. Sounds like you have hot water so why not flow. The mixing valves I have been around didn't have any screen in them maybe yours does. You have a hose bib on the return manifold out of the floor you should open it with the pump running and be able to get a flow of hot water out of it if not then you need to find if the pump is air locked or not working. I guessing you aren't running a heat exchanger with anti freeze on the floor side so you might have to install a hot water filter in the system to remove any dirt or rust that's in your system. The guy that put this in should be able to figure out why your not flowing hot water.
Thanks for your thoughts, Hedge Wood! When I open the bib, I immediately get a flow of cold water, for what it's worth. Not sure what that means in the scope of the overall system, but that's what I'm seeing.
We did have anti freeze in the system initially, but it's boiled over so many times that I'm sure most of the anti freeze is long gone. As for a heat exchanger or hot water filter ... I'm not sure. What you see in the picture above is what I have at the moment.
"The guy that put this in should be able to figure out why your not flowing hot water." Unfortunately, I'm not sure that this is the case. I paid him plenty of money to build the system, and it worked for all of two days (back in November 2021). Real nice guy, but 1) I'm not a priority for him (he knows the system is jacked but hasn't shown any interest in coming out and fixing it), and 2) He doesn't seem to have any idea what the issue is, apart from focusing on the filter screen being potentially clogged. I really wish he could accurately diagnose and fix the problem, especially with my financial investment into the system, but ... here I am trying to figure it out on Hearth.com. That's why I really, really appreciate you guys coming alongside me in this.
We did have anti freeze in the system initially, but it's boiled over so many times that I'm sure most of the anti freeze is long gone. As for a heat exchanger or hot water filter ... I'm not sure. What you see in the picture above is what I have at the moment.
"The guy that put this in should be able to figure out why your not flowing hot water." Unfortunately, I'm not sure that this is the case. I paid him plenty of money to build the system, and it worked for all of two days (back in November 2021). Real nice guy, but 1) I'm not a priority for him (he knows the system is jacked but hasn't shown any interest in coming out and fixing it), and 2) He doesn't seem to have any idea what the issue is, apart from focusing on the filter screen being potentially clogged. I really wish he could accurately diagnose and fix the problem, especially with my financial investment into the system, but ... here I am trying to figure it out on Hearth.com. That's why I really, really appreciate you guys coming alongside me in this.
This valve is off, correct?
![[Hearth.com] Troubleshooting In Floor Heat](https://www.hearth.com/talk/data/attachments/292/292904-89d212d9ec47baabfdc1910432b56609.jpg?hash=bqD14APtyS "[Hearth.com] Troubleshooting In Floor Heat")
When you open this valve, you get cold water? With some pressure? This is on the return line, so if your floor heat hasn’t been on for long, it would be cool.
![[Hearth.com] Troubleshooting In Floor Heat](https://www.hearth.com/talk/data/attachments/292/292905-a9f6f9ca73beefa4c848aa584c3fbed5.jpg?hash=NKRLtUkDa6 "[Hearth.com] Troubleshooting In Floor Heat")
I am not a plumber, nor am I a HVAC tech. Take the following from a construction worker turned floor covering installer, but whose current occupation is teaching school. I also run and troubleshoot my own hydronic system, and am not above a few mistakes. 😁If it were mine I would want another hose bib here. Then you could do a couple of things. #1 Open in to see if there is hot water flow. #2 Connect a garden hose from a hydrant to it, open the other hose bib on the return side, shut all the other valves, and see if you can get water flow through your floor pipes with your garden hose. Like was mentioned, it is possible, though probably unlikely, that they froze up.
![[Hearth.com] Troubleshooting In Floor Heat](https://www.hearth.com/talk/data/attachments/292/292907-ea7982cad441e7b1407026eda43f7209.jpg?hash=G0IEXdiMD2 "[Hearth.com] Troubleshooting In Floor Heat")
When you open this valve, you get cold water? With some pressure? This is on the return line, so if your floor heat hasn’t been on for long, it would be cool.
I am not a plumber, nor am I a HVAC tech. Take the following from a construction worker turned floor covering installer, but whose current occupation is teaching school. I also run and troubleshoot my own hydronic system, and am not above a few mistakes. 😁If it were mine I would want another hose bib here. Then you could do a couple of things. #1 Open in to see if there is hot water flow. #2 Connect a garden hose from a hydrant to it, open the other hose bib on the return side, shut all the other valves, and see if you can get water flow through your floor pipes with your garden hose. Like was mentioned, it is possible, though probably unlikely, that they froze up.
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