Sunday, November 29, 2015

Manual fresh water tank heater: just a hose from the hot water faucet to the tank, but it keeps the pipes from freezing

During our last trip to Sequoia, the outlet hose leading from the water tank to the pump froze one night, when the temp got down to 11 degrees.  When we got home, I rigged up this simple solution:  A hose connects to the water faucet.  The hose runs to the outside through the outdoor shower opening.  The hose runs along the outside wall of the trailer, and the end goes into the external fill pipe of the water tank.  We run a few gallons of hot water, and the temp of the tank is substantially increased.  The warmed-up water runs through the outlet hose and back to the pump.

Here are some photos:

This is the end that screws onto the faucet – I have included a swivel fitting to make it easier to attach:

Here it is attached to the faucet:

The hose runs over the edge of the sink, under the counter, and into the opening for the outdoor shower:

This is a larger view of the hose as it passes through the outdoor shower opening:

This is an exterior view, showing the hose emerging from the outdoor shower opening – I have also inserted tightly-fitting foam blocks into the outdoor shower fixture as extra insulation:

And here is the hose going into the external fill pipe door:

For storage, the whole thing coils up and goes into an under-seat storage bin.

Some thoughts and caveats:

A thermostatically controlled built-in under-counter system would be far better.  But it requires cutting into the plumbing, and some electrical work.  My solution is crude but effective -- very simple and inexpensive.  It does the job, especially if (like us) you rarely camp in weather below 20 degrees.  (We have camped at 20 many times, with no freeze, but this last trip was just a little too cold.)

Obviously, this solution only works if you have an outside shower fixture -- otherwise, how would you get the hose through the wall?  And it is much easier if you have previously removed all of the outdoor shower plumbing fixtures.  (We did that when we got the trailer, because it is always too cold for a late afternoon outside shower when we are boondocking.  We needed the extra room under the sink more than we needed the shower, since we use the inside shower.)

The main drawback to this system is that it has to be set up whenever you want to use it and then taken down whenever you want to change your campsite.  But we so rarely encounter temperatures below 20 that this will be an infrequent event.

The other drawback is that this system does not operate automatically, unlike thermostatically controlled hot water recirculators.  So, for example, I plan on running this device at least once during the night, which will mean that when I get up at 3 am (which I always do), I will have to stand there for three minutes while the hot water runs into the fresh water tank.  Not a deal-breaker, but not effortless, either.  And the water heater will need to stay on during the entire night, which means that it will cycle on and off every few hours, which is a little noisy.  Better than frozen pipes, though!


Michael Jones said...

Your hot water heater is next to your gravity fill in the pictures, you could simplify this by running a hose from the pressure relief valve on the outside of the water heater instead of routing hoses from inside. This keeps everything outside of the camper. Very neat idea overall!

Liz W said...

Hi I think you're the same guy that's on the funfinder forums. Anyway assuming that... Hi!

I have always understood that running water doesn't freeze. So, could you just run regular water not hot water and that way your water heater wouldn't have to turn on all night. Or, maybe even just cut a vent in the water pump area into the living area so the pump would stay a little warmer?

Enjoying your blog! You got some great ideas!