using water heater in below freezing weather

[Pat]

Do these 6 gallon RV  water heaters work OK when it's, say 25 outside?  Or colder?  Water going into the water heater is slightly warmed by a heated water hose. 

How about when it's windy?  Can the water heater burner ever blow out? 

We have a combination of 25s coming up tomorrow.  25 degrees high and 25 mph winds.  More or less.  Water is heated for showers only, so it would have to work an hour or less.  All other freeze protection is in place: heat lamp, open cupboards, heaters going...

Right or wrong, the grey tank valve is left open.  Can't have it freezing shut.  Tanks and pipes are all well insulated. 

 

[kjansen]

Should be no problem leaving and using the water heater. Make sure you don't have a leaking faucet as slow water running in a sewer line can freeze and plug the sewer line.

 

[Ernie n Tara]

I wouldn't worry about the water heater,  but if you really meant 25 deg. high, I'd doubt the rest of the piping will handle the lows.

Ernie

 

[Rene T]

You mentioned you're going to have heaters going. I assume you mean electric space heaters. The problem with that is that the RV furnace will not run as much therefore the basement will get cold. Typically the basement gets some heat from the furnace through the duct work. If you cut back on the use of the RV furnace you could have issues with pipes possibly freezing due to lack of heat. That's only my opinion. Others may feel differently.

 

[Mtn Mike]

We've had no problems operating our suburban 6 gallon water heater in sub 20F temperatures. However, be conscious of the tank when you turn it off. Although the water heater has got a nice foam cacone insulating it within the coach, the outside is basically exposed to the cold. It would probably take a long time for that water to freeze at 25F, but if it did that would be catastrophic  . So when you're done showering, either drain the WH or periodically fire it up to keep the water above freezing. And as was mentioned above, the rest of your water system might need attention too. Welcome to the winter camping club.

 

[John From Detroit]

IN sub freezing weather you need to either

1: Have the water heater FULL and OPERATING (TURNED ON)

or two
Drain it.

So long as it's operating the water will not freeze inside it (The lines to it possibly, The lines from it possibly but not INSIDE it)

But if you shut it off. Bypass and Drain.

 

[NY_Dutch]

We've been in temps down to -4 deg F with no water heater problems or significant pipe freezing. We only run the heater as needed, such as for showers at bedtime. The water is usually still slightly warm in the morning before we run it again.

 

[Rene T]

We've been in temps down to -4 deg F with no water heater problems or significant pipe freezing. We only run the heater as needed, such as for showers at bedtime. The water is usually still slightly warm in the morning before we run it again.

Dutch,
Is there a difference between significant pipe freezing and insignificant?  ;D

 

[NY_Dutch]

Dutch,
Is there a difference between significant pipe freezing and insignificant?  ;D

Yes there is... At -4 the only pipe that froze was a short stub pipe that connects the accumulator to the supply pipe from the pump. The only effect of that was the pump running each time a faucet was turned on, the same as it would with no accumulator. Since all normal water usage was still functional, I consider the freeze up (that took about 5 minutes with a hair dryer to fix) insignificant.

 

[Pat]

I'm in a 24' Chinook.  Everything's inside.  No basement.  I don't run the furnace.  I heat with space heaters.  All inside piping is cozy warm.  Cupboards are open.  25 watt lamp is clamped right next to water heater.  It is covered with foam, but I think it picks up inside warmth, because the whole thing except the outer wall is open to the inside.  Outside water feed is through a heated hose with built-in wiring, so water going into the heater is warmish.   

Never thought to drain the water heater after each shower.  It's not hard to do.  I don't think it's necessary, though, with all the inside warmth it's getting.  Faucets run very normally on hot. 

These Chinooks were built for the north woods, so they said.  Winter hunting and all that. 

Tonight's low is predicted to be lower than last night.  The acid test.  We're about 20 degrees below winter averages for a few days.

 

[Pat]

New help required. 

Attached is a picture of the white plastic water heater valves in the winter position.  No water flows into or out of the heater in this position.  Question:  Do either of those two silver knobs on the floor empty the water heater?  I know one is intended to empty the fresh water tank.  I removed it years ago.  But I'm not sure if one empties the water heater.  Can anyone tell from looking at the pipe configuration?

 

[Rene T]

Those are your low point drains. One is the hot side and the other looks like it's for the cold side. To empty the tank, you have to go outside, open the access door. look at the bottom of the heater and you'll see a hex plug. That needs to be removed in order to drain the tank. If it's a Suburban water heater, there will be a sacrificial anode on the end of the plug. If you have Atwood heater, it will be just a plug.

 

[Pat]

Draining via the outside plug is how I've been draining it for years.  I did it that way today.  Just wondering if there was an easy inside drain.  Thanks. 

 

[Rene T]

Draining via the outside plug is how I've been draining it for years.  I did it that way today.  Just wondering if there was an easy inside drain.  Thanks.

No, you have to do it from outside to make sure you drained all the water. I usually leave the drain plug out till spring. Make sure you shut off the 110 volt AC power (if you have a heating element) before you attempt to drain the tank.
When you open the low point drains, this does not necessarily mean that you've drained all the water. You either have to add the pink stuff or blow down the entire system with compressed air which a lot of people do.

 

[Pat]

Thanks for the extra info.  Never thought to leave the plug out.  Mine's propane. 

 

[Rene T]

Thanks for the extra info.  Never thought to leave the plug out.  Mine's propane.

Most are propane AND 110 Volt AC.

I leave my plug out because when I use to winterize with antifreeze, if there was any chance of fluids getting into water heater tank, I wanted it to drain out. With the plug in, you'll never know.    Even now, I use compressed air and I leave the plug out until I'm done blowing down then I put it back in because I head south 2 months later and I dewinterize the RV on our way to Fl.

 

[Pat]

I live in here fulltime.  However, I think I'll go back to using the campground shower until these really hard freezes stop.  If I need a little bit of hot water, I microwave it.

 

[WILDEBILL308]

When it is cold I just leave the water heater on.
Bill

 

[kjansen]

I think I would play a few games with your system.  If you don't have a check valve in your system, it looks like the left valve would also drain your water heater when you opened it.  When the system is full, I would open the drain valves and let them drain, making sure you have a hot water faucet open or the relief valve.  After everything is drained, I would go outside and open the water heater drain and see how much water would run out.  A small amount of water could stay in the WH and not do any damage.  Even when I open my drain a small amount still stays in my heater and after 13 years have never had an issue.

 

[Rene T]

I think I would play a few games with your system.  If you don't have a check valve in your system, it looks like the left valve would also drain your water heater when you opened it.  When the system is full, I would open the drain valves and let them drain, making sure you have a hot water faucet open or the relief valve.  After everything is drained, I would go outside and open the water heater drain and see how much water would run out.  A small amount of water could stay in the WH and not do any damage.  Even when I open my drain a small amount still stays in my heater and after 13 years have never had an issue.

Open all the faucets to make sure everything drains out. Then do as Kevin recommended with the heater drain plug.