Heating space between hulls

[Jim and Chris Neuman]

Living on the Northwest coast of Washington we rarely get temperatures low enough to cause freezing issues while in winter storage.  It does happen though and the potential for freezing damage does typically raise its head a few times each year while during the winter months.

I have been giving some thought to the installation of an electric heater designed to keep warm air moving between the hulls when temps drop into the 10's & 20's.  A small, high quality electric heater permanently installed which draws in cabin air and routes it through areas between the lower hulls where plumbing and other temperature sensitive components live could serve the dual purpose of protecting trailer components from freezng and help keep things warmish and dry.

I understand this system would only be functional while on shore power.  Anyone here designed and installed such a system?  

[theOrca]

I did. It should be findable as I posted pictures and instructions.

Essentially I opened the third port on the Dometic heater and hard ducted it directly across the rear of the trailer. Turned 90 degrees forward and installed a flow adjuster right after it reentered the underbed area. I placed a diverter at that point, and sent part of the warm air directly down under the drivers side bunk. I also installed a 3" flex line running forward all the way to the forward dinette seat. I have been in minus 18 degree F temps in Republic, and the minimum temp under either bunk was 38 degrees. My friends trailer water froze every night by 9 pm. It is tight, but doable!

The electric option just would not work for me as I use my Olly as an Elk Camp Cabin. I wanted an extra propane heat load, not an extra electric load.

Edited yesterday at 04:48 AM by theOrca

[Geronimo John]

Several owners have added individuall heaters in the intersticial space between the hulls.  The top choice is to get heat to the water liness entry area aft of the port bunk.  This area tends to freeze first.  I recall that he used a 500 watt 120V heater for this purpose.  A second area prone to freezing is the cabinet space in the bathroom.  For occasional use this would in my opinion be enough.  

However if you are where The Orca is, a forced air approach would be desireable.  Intake air from the cabin and distribute it to both port and starboardd areas with extra air going on the port rear side would be my choice.

GJ

[Allons-Y]

I installed a 500W  "xtreme" bilge heater.  It is on a thermostat to maintain a temp of ~ 50f.  I have used it for the past few winters and have added a special circuit to plug it in.

They are available from xTreme heaters and Amazon. 

[theOrca]

12 hours ago, Allons-Y said:

I installed a 500W  "xtreme" bilge heater.  It is on a thermostat to maintain a temp of ~ 50f.  I have used it for the past few winters and have added a special circuit to plug it in.

They are available from xTreme heaters and Amazon. 

That was my first thought, and a much simpler solution than changing the ducting. The only downside I could see is that it requires 24/7 shore power.