Troubleshooting Cold Water From An Excel RV Tankless Water Heater

Question:

I just bought and installed a excel tankless water heater. I ran the same one last year but forgot to drain water out of it back in the winter and the heat exchanger busted so I went and bought a brand new one today. After hooking it up and running it the same way I have in the past it’s not getting hot at all like barely warm water coming from it, even with everything set to the max settings. If I turn my hot water off and let it build it it gets really hot but as soon as I turn hot water back on it goes back to warmish water. It’s almost like the water is going so fast it don’t have time to keep it warm or something. Please help haha

asked by: Bukiedean

Expert Reply:

The only real troubleshooting you can do on the Excel RV Tankless Water Heater # EX93FR is to ensure that you have the proper water and gas pressure running to the unit and that there's two good D-batteries in it. I would start by checking the batteries as this is the simplest step.

After that the water pressure, this unit was designed to work 2psi - 120psi water pressure but if it's too high it'll obviously rush through the unit quicker than it needs to fully heat up. If you are running off of city water then I recommend picking up a regulator like # 37262215 to drop it down to 50-55psi, which is the slightly above the standard 40-50psi water pressure typically recommended for RV's.

The last thing to check would be the gas pressure to ensure you're getting 11" WC. This is something only a technician can check with a meter. You may have a clogged up regulator that just needs to be cleaned and readjusted to send proper pressure to the unit. If the regulator is bad I'll just need to see a picture of it to find the correct replacement to fit your system.

If none of this fixes the issue I would reach out to Excel for a warranty claim, as it would be some sort of internal manufacturer defect.

expert reply by: Kevin C