Hot Water Heater Works But No Hot Water

[Althea]

Greetings- For the 3rd year in a row, we had the pleasure of de-winterizing our Safari in prep for the season. All went well with purging antifreeze, putting in fresh water, removing air from the water heater, and getting water flowing from all lines. Water pump, fridge, heat in all working condition. The step that we save for last is to fire up the water heater. After ensuring the bypass valve is in the right position, we flip on the switch and it ignites like a charm! Sweet - time to celebrate! We patiently wait for the water to heat up. Every 5 minutes we turn on the hot water and it's not hot. Hmmm...well, the water in the fresh water tank is pretty cold, having just filled it with city water so we continue to wait. After about 15 minutes the hot water heater turns off on its own (I believe there's a sensor that will automatically shut it down if it's on too long or gets too hot). We check for hot water - it's still room temp. Bummer - something's up. So, we call it a day so we can pause and do some research. Any suggestions? Thanks for your help.

[aftermath]

I would go back and double check the HW bypass. I am embarrassed to admit it but after a few years of spring preparation I missed the bypass one time. With an empty tank I fired it up and it shut down, but not right away. It hit me that I had made this mistake so I let it cool down and the next day I opened the valves and filled the tank. No damage done.

I can't think of anything else. You might have water flowing into your tank but the middle valve might still be open. This would give you some warm water because it is mixing cold with the hot from the tank.

[CBWELL]

Open the outside door for the heater and lift the relief valve slightly, with the system pressured up. If you have no water some out, you have not opened the valves correctly on the bypass. Make sure to wear gloves when opening the valve as the water might be hot. I normaly open the relief valve when dewinterizing just to confirm that the tank is full before starting it. Chris

[Seinbelld]

Hi all,

Inaugural camping trip with our new Serenity 30'. Have figured out most things but we haven't been able to get hot water. We were also smart enough to leave the manuals AT HOME. We de-winterized the trailer and opened what we thought was the bypass but all it did was drain the water out. Total noob question but would someone mind walking thru the steps of what to do to get hot water after de-winterizing... We obviously skipped one.

Thanks guys,
Eric

[HowieE]

The bypass on the heater is along side of the heater and most often reached under the bathroom sink cabinet. Sounds like you used the drain plug and got to it from the outside of the trailer through the heater access door.

If you can draw water from a faucet while having selected Hot and you are getting just cold water I would check the bypass valve.

[pmclemore]

I've had the same problem the last two years after I winterized the trailer (including by-passing the water heater and completely draining it. Nothing I did could get water to come out of the hot water tap. Yes, the bypass valves were set correctly. I gave up on it the first time it happened and went shopping for a new tank. Luckily I didn't find one. When I arrived at the next camp, it worked perfectly.

I think the matter is that since the water tank is empty, there is no "demand" when you open the tap - perhaps an air dam of some sort. So nothing happens. My latest method is to fill the water heater tank completely, letting water spill from the pressure valve.before opening the tap.

If that doesn't work, pack up and go to the next stop.

Pat

[HowieE]

It is very dangerous to light the hot water heater before you have filled the tank and have water flowing from the tap.

Once drained for winterizing it takes about 5 minutes to fill the tank. During that time you want to have a hot water faucet opened to allow the air to escape. The flow of air during this time indicates the bypass valve is open and water is filling the tank.

If you light the heater before it is full you run of damaging the heater itself or a risk of explosion.

You should not use the safety valve on the heater as a means of purging the air. Those valves are not designed or intended to be used as a drain. Opening the valve runs the risk of changing the operating points of the valve and thus losing the designed safety feature.