Mysterious Midnight Water Heater Clicking

[zapper]

While running on shore power and have the electric hot water heating element only switched on, I notice a periodic faint clicking always in the very late night or early morning hours. Never during the times when we are normally awake. If I shut off the heating element the sound stops. I have replaced the water heater control electronics, with no sucess.

I am guessing that as the WH approaches set temp, I am hearing the shut off call for heat switch cycle?

Is this normal?

-Hugh

[ITSNO60]

Originally Posted by zapper

While running on shore power and have the electric hot water heating element only switched on, I notice a periodic faint clicking always in the very late night or early morning hours. Never during the times when we are normally awake. If I shut off the heating element the sound stops. I have replaced the water heater control electronics, with no sucess.

I am guessing that as the WH approaches set temp, I am hearing the shut off call for heat switch cycle?

Is this normal?

-Hugh

Yes you are going to hear noise as there is a thermostat and a relay, anytime you have a substantial load like a heating element it is normally going to be switched on and off with a relay that can handle the current, relays click when they activate. You may also have a load selecting device that some RVs have when the water heater shares a circuit with another appliance like the microwave, it will cut power to the water heater when the microwave is switched on then restore power after a set time when the microwave is finished, this makes a clicking sound as well.

[zapper]

Got it thanks. I understand the switching clicks, but this is more like a series of clicks like a continuous buzz for about 5 seconds.

[Al and Missy]

Originally Posted by zapper

Got it thanks. I understand the switching clicks, but this is more like a series of clicks like a continuous buzz for about 5 seconds.

My 2002 vintage water heater has two thermal shutoffs. One is at the desired water temperature and one is an over-temp protection device. Assuming your water is not excessively hot, I would suspect the normal shutoff switch is not making good contact and causing the control electronics to chatter the relay. The other option is the relay itself has bad contacts and you are hearing arcing until to connection makes or breaks. There shutoffs are behind a cardboard cover accessible from the front of the heater. In my trailer that is behind a trim panel below the cabinet door under the bathroom sink. One of mine failed and I had to replace it, but the symptom was the heater would not work at all.

[JoeHTP]

Our relief valve made weird noises at night before it completely broke and leaked.

[Sport 16 STL]

We always turn off water heater during the night. Why heat water when no one is using it.

[jrwayne]

hi,

water will stay hot for hours. great feature for boondocking.

[SuperTrouper]

Originally Posted by Sport 16 STL

We always turn off water heater during the night. Why heat water when no one is using it.

I think the sound is prolly happening all the time but you only hear it at night. Al and Missy have a point regarding chattering relays. Might want to check that out. Ours is gas only so we turn it off at night to avoid middle of the night firings and it's always warm enough to wash your face in the morning. Turn it on when you rise and it'll be ready for a shower in no time. - Brad

[zapper]

Thanks for all the input. Something to think about and not worry. If it fails, I'll replace it. It was just a bit random and puzzling.

Growing up I tended fixate on mechanical anomalies, especially weird sounds. Probably came from owning too many British sports cars, Cause when you heard something that didn't belong, disaster wasn't far behind; like a spoke wheel leaving the car when the knock-off flew ahead of the car. Oops.