troubleshooting a tempering valve
#1
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troubleshooting a tempering valve
I have a sparco/honeywell AM101C tempering valve on my DHW supply. Been working fine until the other day we started getting tap temps noticeably below the set temp, but not awful. The indirect seems to be fine (i.e., this does not appear to be a problem on the tank side). I turned the mixing valve's adjustment knob all the way down and back a couple times. That or something else appears to have fixed it, at least 96% of the way (need to put a temp probe on the taps to be sure).
Question: do these valves ever get a piece of junk in them, or get stuck, or whatever? Other things to check?
Thanks.
Question: do these valves ever get a piece of junk in them, or get stuck, or whatever? Other things to check?
Thanks.
#2
I find that the problem is typically the mixing valve or the coil(sediment).
The mixing valve is by far the cheapest and easiest to replace. Yes, I have had some fail in a way that very little hot water was mixed in.
On my parents boiler, I replaced the mixing valve and it made a big difference, but after 3-4 minutes of hot water use, it cooled down. I ended up replacing the coil and that solved the rest of the problem. The mixing valve was first not mixing well, and the coil had enough minerals and other stuff built on it that the water had to stay in the coil much longer to actually warm up.
I would start with replacing the mixing valve.
The mixing valve is by far the cheapest and easiest to replace. Yes, I have had some fail in a way that very little hot water was mixed in.
On my parents boiler, I replaced the mixing valve and it made a big difference, but after 3-4 minutes of hot water use, it cooled down. I ended up replacing the coil and that solved the rest of the problem. The mixing valve was first not mixing well, and the coil had enough minerals and other stuff built on it that the water had to stay in the coil much longer to actually warm up.
I would start with replacing the mixing valve.
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Thanks. Forgot a key piece of information: the valve is only about three weeks old. Worked fine until the other day, had an issue for a couple days, now it appears to be mostly back to its old self.
No coil here; it's plumbed off an indirect water heater. Water quality very good here. Fairly new indirect tank (3 yr old).
No coil here; it's plumbed off an indirect water heater. Water quality very good here. Fairly new indirect tank (3 yr old).
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Tempering Valve
Propably a spec of solder or other debris got in there. If it doesn't want to act right: (a) Call your installer back since it should be a warranty issue. OR (b) Get out the big hammer.
The hammer won't help the hot water issue but it might make you feel better for a while.
The hammer won't help the hot water issue but it might make you feel better for a while.
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Now Pete don't go dissing my installer.
He's a great guy and does quality work. Also on vacation this week.
I have the instruction sheet, and the manual, spec sheet and everything else that came with all the equipment. And all of it's on-line anyway and was committed to memory months ago....
I'll forgo the hammer, thanks.

I have the instruction sheet, and the manual, spec sheet and everything else that came with all the equipment. And all of it's on-line anyway and was committed to memory months ago....
I'll forgo the hammer, thanks.