Water circulator for freeze protection

[hugh]

I've been thinking about adding freeze protection to my tanks, drains and outside water lines for cold weather camping.

It seems like the normal way to do this is with heating pads on the tanks, and heater wire wrapped around the pipes. But running several hundred watts of electric heating means I'd always have to be plugged in.

As an alternative, I've been considering adding a circulation pump off the hot water line, which would feed a long run of 1/4" PEX wrapped around the water lines and tanks. Basically, it would turn the hot water heater into a closed loop radiator system to keep the pipes from freezing.

Anyone tried doing this? Any thoughts from the engineers out there?

[HABBERDABBER]

At first glance, you'd be adding another water system with the potential to freeze up. I'm no plumber, but with a flush enough checkbook one can do most anything. But why?

Any water system would still be marginal in really cold conditions (0 F) unless the system and tubing were very well insulated. The PEX plastic is not a good conductor of heat transfer to keep your intended items warm. Aluminum, or copper tubing would be much better for heat transfer. The PEX is very strong and durable stuff, but even it and all the inter- connections especially are vulnerable to freeze damage.

K.I.S.S. There are ways and means to use your rig in cold weather. The question is just how cold do you want to be able to use it, and for how long?

Cold weather Escape use has been discussed extensively on this forum. Do a forum key word search.

[hugh]

Originally Posted by HABBERDABBER

At first glance, you'd be adding another water system with the potential to freeze up. I'm no plumber, but with a flush enough checkbook one can do most anything. But why?

Any water system would still be marginal in really cold conditions (0 F) unless the system and tubing were very well insulated. The PEX plastic is not a good conductor of heat transfer to keep your intended items warm. Aluminum, or copper tubing would be much better for heat transfer. The PEX is very strong and durable stuff, but even it and all the inter- connections especially are vulnerable to freeze damage.

K.I.S.S. There are ways and means to use your rig in cold weather. The question is just how cold do you want to be able to use it, and for how long?

Cold weather Escape use has been discussed extensively on this forum. Do a forum key word search.

Yeah, idea is to get long weekend use (3-4 days) in daytime temperatures below freezing (20 degrees or so), without plugging into a power outlet.


Maybe I missed something when I searched, but I didn't see anybody doing that. (well, with a working plumbing system anyway )

[HABBERDABBER]

No, nobody I am aware of has done a hot water based exterior tank warming system. Someone did post a query of using the hot water tank as a boiler for cabin heating.

My suggestion for a forum search relates to methods, equipment and techniques to camp comfortably in below freezing weather.

[hugh]

Originally Posted by HABBERDABBER

No, nobody I am aware of has done a hot water based exterior tank warming system. Someone did post query of using the hot water tank as a boiler for cabin heating.

My suggestion for a forum search relates to methods, equipment and techniques to camp comfortably in below freezing weather.

Yeah, I'm definitely new to winter camping in a trailer.


That said, I've spent many months winter tent camping (used to do a lot of mountaineering), so anything in the trailer seems like pure luxury in comparison.

[HABBERDABBER]

Have your rig winterized, with the water lines blown out, et al. Bring plenty of water and keep it liquid. Use some for manual flushing of the toilet. Add some RV anti-freeze to black & grey tanks. Get a small solar shower bag, heat water on the stove for a nice warm shower. Go without the luxury of hot, running water on demand. The rest of the luxuries are available.
Operating from lead acid batteries, you have 1, maybe 2 days of furnace use, which is a limiting factor for winter boondocking. Lights, heat, shelter, cook stove, indoor toilet, soft bed.......the rest you have.

That's what I'd do. Protecting all you envision from freezing could be a real Rube Goldberg contraption.

[Keith3]

Originally Posted by HABBERDABBER

No, nobody I am aware of has done a hot water based exterior tank warming system. Someone did post a query of using the hot water tank as a boiler for cabin heating.

My suggestion for a forum search relates to methods, equipment and techniques to camp comfortably in below freezing weather.

I was the person looking at using radiators off the water heater. Dickinson Marine has some nice radiators with 12v fans, but when I contacted them they recommended against using theirs with drinking water due to the materials not being selected for drinking water safety. They just weren’t sure how it may contaminate the water. I appreciated their honesty.

For the op I wonder if a simple 1/4 hot water line dumping into the fresh water tank would be enough to keep the tank from freezing. Assuming that you have the spray on insulation you could snake a thermometer into the tank and have a valve open when the temp gets below a preset number, like 38 F or so. Dump a bit oh hot water, pull water through the main water line. If the trailer is otherwise warm that may work out fine. (Thermostatically controlled valve is your problem to solve.)

What everyone else says is true, but it’s fun to play Rube Goldberg games in your head.

[alanmalk]

Originally Posted by HABBERDABBER

No, nobody I am aware of has done a hot water based exterior tank warming system.

...

I did something quite similar.

With help from Reace back in the "old days", we installed a T in the bypass line of the water heater (the short winterizing line). This lets me tap into hot water independently of the main line to the fixtures. From the T a tube runs back to the fresh water tank via the air vent line. The idea being that I can dump hot fresh water back into the fresh water keeping it above freezing.

But - and we've met this "but" before - I have never used it. 2 reasons: After 7 years I wonder what is growing in this tube that I can't sterilize, and second, I don't intend to camp where temps fall below freezing during the daytime.