Lesson 8: Heating and cooling overview



To turn the furnace on, use your thermostat and set the heat higher than ambient temperature. Make sure your propane is turned on. You will feel heat through the vents, as well as from the outside furnace vent on the side of the coach.

You can use the furnace without house power – it only requires propane and battery power.



If you have AC ducts throughout the coach, then your AC is controlled by a thermostat on the wall. You also can set the speed of the fan (hi, low, auto) as well as the temperature.

Remember that you need to have either generator or shore power to run the air conditioner – it doesn’t run on batteries.

We cover much more in the video, so be sure to watch!

MasterTrack Lesson

Coaches are cooled using roof-mounted air conditioners, anywhere between 1 and 3 units. These are usually controlled by a thermostat/control panel. Heat is usually either an Aquahot system or a propane furnace. Coach propane furnaces are actually quite effective, but notoriously inefficient, as it vents combusted hot air outside the coach.

Many people don’t know this, but air conditioning is only capable of reducing the ambient air by about 20 degrees. This means that if you are in your coach on a hot 100 degree day, you can only get the coach down to 80 degrees! Sometimes people will think their A/C is not working, but it is!

Aquahot/Hyrdohot: Your system runs on both electric and a diesel burning boiler. This system provides heat and hot water on demand. For long hot water on demand, use burner (not electric, it can’t keep up). When the engine is running, it pumps coolant through system for heat transfer (more efficiency). There is no hot water tank!

Heat strips: Don’t work below about 50 degrees, some 40.

Heat pumps: A heat pump is a part of the air conditioner that basically is air conditioning backwards: Rather than pulling heat from the air and circulating it, it pulls cold from the air and circulates the heat. Most units will auto-switch to the furnace once ambient temperature reaches near 40 degrees, as the heat pump doesn’t work below that temperature.

AC Power draw: Although air conditioners can run with relatively low amps, when the pump kicks on it spikes the amps dramatically. This is why you cannot run air conditioners on battery power (rare exceptions). If you try to run the air conditioner(s) without enough power, they will simply not start. It’s possible that they’ll start and then blow a fuse, but in most cases they just won’t start. You must have the generator running or be plugged into shore power to run the A/C. If you are plugged into 20 amp service, you probably can’t even get one started. With 30 amp service, you can run one and if you’re luck two. If you have 50 amp service, you can run 2 or 3 at the same time depending on what else is currently drawing power.

It’s important to note that the dash a/c and heat run from the engine like a normal car or truck. They are independent of the heating/cooling system in the house portion of the coach. If you are traveling with people, and the house starts to get hot, you can run the generator while driving in order to run the A/C units for your guests. If you’re in cold weather, personal heaters work well for house heat while traveling (however the generator generally needs to be running as well, as space heaters draw huge amounts of power).

Video Lesson