When my hot, water heater runs out of hot water, I have to wait a while until it's hot again. I'd like a way to check the temperature without running water to the faucet every 10 minutes.

Is it possible to put a temperature probe in the heater, and a display unit elsewhere?

(This specific unit is a propane-fired RV unit, with a 6 gallon tank, hence the running out. But I invite answers for regular house units as well.)

1 Answer 1


I don't see why not. In fact, all heaters I've seen are sold with a temperature probe on the inside and a display on the outside. I don't know why yours isn't. The problem is, of course, that you need to somehow get the probe on the inside - you must find a way, we don't know the construction of the heater.

The easiest thing to use (provided you can think of a way to insert the probe) would be a digital roasting thermometer.

roasting thermometer

The probe is stainless steel, so it won't rust in the water. It has a flexible connection to the processor/display unit. It has a limited temperature range, but 15°C to 100°C should be covered. The price is in the 20 - 30 Eur range. Maybe you can even put the "alarm when a temperature has been reached" into use, or get one of the radio models - they display the temperature on a second wireless display within a limited range, probably strong enough for another room. I don't know what the drain on the batteries will be during constant use, it might be a drawback. So try to get a mignon powered one instead of button cells.

  • I think I just found another reason to like Germany. I've never seen a temp display on any water heaters in the US, with the exception of a solar device.
    – BMitch
    Jul 3, 2011 at 17:00
  • Maybe there is a difference in the type of heaters. I am talking about small (50-100 l) electric heaters mounted in the room they are used, I don't know if central heaters meant for the basement have that feature. And the analog displays are very primitive, without numbers on the scale. But enough to know when the water is "hot" or "cold".
    – rumtscho
    Jul 3, 2011 at 17:07

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.