Okay... so the AQUAHOT is the electric water heater and works rather slowly, the DIESEL BURNER is the fast water heater and will maintain hot water as it is used, and the HYDOHOT is the whole waterheating unit? To use the AQUAHOT you must have either generator or minimum 30 amp shore power. To use the DIESEL BURNER you will need more than roughly 1/4 tank of diesel because it pulls its diesel from roughly the 1/4 tank level so you cannot use all your diesel while camping. And, by the way, your generator also takes its diesel from about the 1/4 tank level. The furnace can be turned on at the thermostat, but if the HYDOHOT (waterheating unit) doesn't have the water temperature up, then the furnace fans won't operate until the water temperature is up.
Bottom line - don't plan on camping in cold weather and using your DIESEL BURNER or generator if your diesel tank is near 1/4 full. Get it filled BEFORE that cold weather camping excursion.
There is reasoning behind the 1/4 tank part. The idea is that you won't identically use up all your fuel and not be able to drive to get it.
The heating system is one unit made by one company. The names of the company and 20 models have changed.
Insided the unit are three sources of heat. One is electric and is limited in output equal to the total amount that can come from a portable plug in heater. The second is a much larger burner that consumes fuel from your one and only fuel tank. The third is the motorhome engine itself. To heat the motorhome, one or all of these three can be operating. The first two are turned on by switches somewhere in your motorhome.
You can get heat out of the system in two ways. One is hot water that you get when you turn on the tap. The other is hot air that you get when you turn on one a thermostat, select the furnace mode and set a a room temperature. You can get a little hot air or hot water when you are only using the electric part of the heating unit. You can get lots when you turn on the diesel part.
The thermostats have an additional function and, in most cases, share the brand name of your air conditioning units. The thermostats can be set to "Heat Pump" or "Cooling".
Be careful of relying on a 30 amp source. It is barely enough to run a large motorhome. If your refrigerator, battery charger and the electric part of the heating system are on you are close to using up all 30 amps. A toaster or hair dryer will overload it and the breaker at the power pole will trip.
It is obvious that 50 amps is better. What is not obvious is that "50 amp hookups" means a pair of 50 amp circuits, or 100 amps. With 100 amps you can use everything Beaver put in your motorhome for you.
When we are on a 30 amp hookup the fridge is put on propane, the battery charge rate is lowered, the electric portion of the heating system is on and we have the "one appliance" rule.
When it is cold enough to need heat, our primary heat source is a portable baseboard heater. It is silent and safe. The HydroHot heating system is noisy. If we don't stay warm enough, then we use the diesel burner.
All of our phone numbers are listed in the Beaver directory. Call anyone, tell them you are a new Beaver owner and you'll get lots of friendly help. Better, make friends with a Beaver owner and get a "walk around" and briefing. Best, go to a BAC Rally.
