FAQ - On RV hot water systems

My HWS is not hot enough

Q:
I have a gas/electric unit in my caravan and I have noticed that the water does not get very hot on either gas or 240v. I suspect that the previous owner may have ran the system on gas with the AC switch on. I have replaced the anode and flushed the tank out. I have also tried pushing the reset buttons after the unit has cooled down. However the temperature of the water is still not very hot on either gas or electric. Could you suggest a solution to my problem ? Chris
A:
Hello, Possibly underneath the van there is a tempering valve. Both hot and cold run into this valve. Have a play with it and see if it makes a difference. It is not uncommon that some people turn this down below the specified 55 degrees. Regards, Mike (Caravans Plus Technical)
Reply:
Hi Mike, I tried that over the weekend and it seems to have fixed the problem.
Thanks for your help, Regards Chris

Q:
Hi, I have a instant gas HWS and the temperature either does not get hot enough, or the water flow is so low that its useless for the shower. How can I fix this? Peter
A:
Hi Peter, You didn't indicate the size or brand of your HWS but instant gas HWS's do have limitations. I guess you have checked your gas jet is not partially blocked. If all seems well on the gas flame side (yellow flames indicate a problem), you may need to go to a larger instant HWS or go to a storage HWS system. The reason instant HWS systems can struggle in certain areas is due to the incoming water temperature.

If you are in a cold climate, either your tank water or the incoming mains water will be a low temperature. The instant gas HWS has a limit on the amount it can raise the temperature during the time it flows through the HWS. You can slow down the water flow to get it very hot but this will cause problems when used for a shower.

A further complication of slow flow if you are pumping your water is that most common pumps used in RV's must switch off and on during your shower. You can reduce this pulsation by installing a pulsation dampener, but you can not eliminate it unless you go to a variable speed pump.

Q:
I am wanting to put a cheap instant electric hot water system in my caravan to run a shower. What would you recommend?

A:
There are some instant HWSs that run on electricity, but when in a caravan they are limited by the amount of electricity that can come through a 15amp power cord. This by its very nature will either give warm water at a reasonable flow-rate or hot water at a slow flow-rate. The only way to increase the flow-rate would be to start with warmer water.

Our recommendation is to use a storage hot water system.