Hydronic Tent Trailer Heating

[mrblaine]

I came across an article on the web about a guy who heated his 24 foot travel trailer with a home brew hydronic heating system.

For those who don't think they are familiar with the concept, I'd venture that no one isn't, you just have never heard it called by it's proper name.

Essentially you circulate heated water through a water to air heat exchanger and blow air through it to extract the heat and circulate it into a living space. (think heater in your vehicle)

The touted benefits are it's much safer with no fumes at all. The heat is of a different nature being more radiant and smoother if you will, without the harshness of a forced air furnace with it's higher on and off temperature differences.

I built a working prototype with parts in my garage in a few hours and so far I am highly impressed. So much so that I may consider one for the camper.

The basic design is a Setrab oil cooler as the heat exchanger, a pair of computer fans on a dimmer switch, our shower water heater, a propane tank and a small circulation pump.

The water heater is used to heat the water and then it's circulated through the heat exchanger. The pair of 4" muffin fans then blow air through the core of the exchanger and warm air is dispensed out the other side.

The goal is to solve a few minor problems and drive the efficiency of the system way up and not have any portion of it be louder than the burner on the water heater.

I found some near silent computer fans with a 6db sound level that accept variable input DC voltage. It remains to be seen if the variable input voltage will also vary the blade speed which we need. Being DC though, they should be controllable with a DC motor speed controller.

I also found a miniscule pump for circulation that is brushless and it will need to be tested for it's sound level and efficiency, although at 2.5" square and 95 gallons an hour, I don't think anything more efficient is available for the price.

I am testing with a small single fixture RV pump slightly smaller than the orange juice glass at the cheap restaurants and it's a whiny little beast, so that will have to change.

The goal is to have the majority of the system be able to be run during the daylight hours on a portion of the output from a decently sized solar panel for the electrical side and then not have it cycle the water heater enough that propane use becomes exorbitant.

I'll get some pictures of the process as it gets more refined.