I started another post thinking that there was a problem with my water heater thermostat, which I ended up replacing. But my water heater works fine, except when I run the Watts recirculating pump I have installed in the system and then it trips the thermostat after working and doing what it should do for a short time. This pump has been working fine for the last three years with no problems. It is still recirculating water as it is supposed to do, but now all of a sudden it is tripping the thermostat on the water heater after working for a little length of time. What could be wrong? I really need this in my system as it takes a ridiculously long time to get hot water at my kitchen sink without it.
Water Recirculating Pump Tripping Thermostat on Water Heater
- Thread starter tonyn1
- Start date
Users who are viewing this thread
John Gayewski
In the Trades
What is the symptom? As in why is this a problem? Are you running out of hot water quickly?
Sponsor
Paid Advertisement
I thought I explained it pretty well. If I don't run the recirculating pump, the thermostat doesn't trip, but then it takes forever to get hot water where I need it, which is why I installed the pump in the first place. It had been working fine for 3 years, but suddenly is making the thermostat trip, though it is still recirculating like it should.
Tuttles Revenge
In the Trades
- Messages
- 4,205
- Reaction score
- 1,459
- Points
- 113
When you say "Tripping" you mean the reset button on the thermostat. That should have nothing to do with the recirculating pump as they're wired from different circuits or should be.. It could be related if perhaps the recirc is causing the elements to run longer and the reset is on the verge already.
The t-stat is likely tripping because one of the components in its system is going bad. Could be a t-stat, bad element or loose wire on one of the components. I'd try checking all the connections first, then using a multimeter to determine if the elements are fully resistant or if the t-stats are working properly.
The t-stat is likely tripping because one of the components in its system is going bad. Could be a t-stat, bad element or loose wire on one of the components. I'd try checking all the connections first, then using a multimeter to determine if the elements are fully resistant or if the t-stats are working properly.
John Gayewski
In the Trades
How do you know the thermostat isn't tripping? The water never gets hot and your assuming it's the thermostat? How can you tell the thermostat should trip and isn't?
Jeff H Young
In the Trades
I think he is saying when he turns on circ pump it circulates hot water . but a short time later ( minutes , days , weeks I dont know what a short time later means) the red button upper t state trips and then he starts circulating cold water because the heater no longer makes hot water.
Seems to me that 2 upper t stats have been reported to repeatedly trip the high limit switch. Meaning its overheating. Only thing I could think of is lower the temp on the t stats. I dont think his circulation pumpcan be causing it
WorthFlorida
Clinical Trail 5th session completed 4/24/24.
John Young's description is on the right track.
You'll need a clamp meter to check the current for each of the two elements. With a cold tank the top element is turned on first. Once the set temperature is satisfied the upper thermostat switches to the lower element.The elements are 4500 watts each at 240 volts and it'll draw approximately 18.75 amps. With wires removed from the thermostat, each element will be ~12-13 ohms each.
What is happening as the water circulates with a hot tank, the lower element will turn on as the temperature goes below its set temper (120º), if the top thermostat water get below the set temperature, it switched power to the upper heating element, then it trips the thermostat because the upper heating element is bad. Corrosion on will occur on a heating element and burn a hole in it and that is a short or over current. I seen when doing an ohm meter check, the element will check OK on resistance and other times it an open. But I do not think this is the scenario.
The magic going on is when after the thermostat has it's breaker tripped, assuming its the upper element will turn on first, it does not make sence its the upper element because you do get hot water eventually, therefore, I'm assuming the lower heating element is bad. When you reset the thermostat, water gets hot from the upper element then switched to the lower element and, but with out the circulator running there is no trip. If this happen in a few minutes the lower element is turning on and it trips the upper thermostat.
I would do a current or ohm test and replace both elements since the short may be intermittent. They are not that expensive, $12-$15 each at home depot.
John Gayewski
In the Trades
We have no idea what's happening becuse he keeps saying it's tripping without describing what's happening. The overload tripping and the circulator have nothing to do with one another.
An overload being tripped shouldn't happen, a thermostat being tripped in most descriptions just means it's working. The water gets hot, the thermostat trips and shuts down the element. An overload means the temp is getting too high. Could be electrical resistance causing that, a short, bad wiring, the breaker, or bad reset. Since the whole thermostat has been replaced it's down to the element or wiring or breaker.
An overload being tripped shouldn't happen, a thermostat being tripped in most descriptions just means it's working. The water gets hot, the thermostat trips and shuts down the element. An overload means the temp is getting too high. Could be electrical resistance causing that, a short, bad wiring, the breaker, or bad reset. Since the whole thermostat has been replaced it's down to the element or wiring or breaker.
Similar threads
