Hurricane Engine Heat

[Carl Boger]

On my way home from Florida earlier this month, I discovered that my Hurricane heating system was not working.  Once I got home I bought and added about 1//2 gallon of boiler mix to the system.  This allowed the system to start and to continue running for over two hours raising the temp from the 60's to 77 degrees.  It cycled on and off normally so I moved on to the next problem of the Engine Heat light not coming on.

I tested the light and found it was burned out so I replaced the light.  Still no light.  I verified that the new bulb was good by hooking it up to 12 volts and it did light up.  I checked the wire to the back of the switch and over to the light and I am getting just under 12 volts there, 11.86 or there abouts.

When I was driving home I had the Engine Heat switch turned on and the Water Pump switch turned on.  The Engine heat light was lit up and the Water Pump at the Hurricane heating system was running.  It will back feed the light in the far right of the picture slightly illuminating it.  The Water Pump for the fresh water system lights it up fully when it is turned on so I believe that light is for the  fresh water pump.

Now down to my real question(s).  Is there a switch at the engine that opens when I turn on the Engine heat switch?  If so any idea where it might be?  The Hurricane operating manual is fairly generic and vague.  I rarely need to use the heating system so I have never turned it on much  unless I was also  exercising the generator.

My thought was that I needed to turn on the Hurricane Pump, and the Engine Heat switch to preheat the engine and to use the engine as a heat source while traveling.  I have traveled this way in the past and had heat in the coach.

Right now I believe the Engine Heat light will not turn on because whatever it is wired to is not working and completing the circuit.

Anything to point me in the right direction would be greatly appreciated.

[Fred Brooks]

   Greetings Carl,
  The way the Hurricane is engineered and Beaver installed it has a loop of engine coolant going thru the water heater that heats the hot water. This is so you have hot water on demand in transit without running your Hurricane. There is an auxiliary coolant pump supplied by Hurricane that is mounted next to the Hurricane heater that is part of that loop. Here is how that works: When you turn on the Hurricane heater and you want to pre-heat your engine because it is wintertime, you turn on the switch in the consol that says engine preheat. This activates the auxiliary coolant pump. The Hurricane heater is now heating the water heater which in turn heats the engine coolant loop inside the water heater and then sends it to the engine block and then back to the water heater. This takes usually an hour to raise the engine coolant 10 degrees but is dependent upon outside ambient temperature. Never leave that Preheat switch in the ON position once you depart and start driving. If you forget, not only is the engine getting hot from throttle demand, but the Hurricane is also heating your engine thru the coolant loop inside your water heater. Hope this helps, Fred    BTW Happy Thanksgiving!

[David T. Richelderfer]

In our coach, the two switches say "Diesel Burner" and "Engine PreHeat" leading to less confusion.  Carl's coach's switch simply says "Engine Heat", leading to the question of whether it needs to be ON for PRE-heating the engine or ON for heating the Hurricane's water/coolant from the engine.

BTW, we have an AquaHot, not a Hurricane, and both switches mentioned above have lights ON when switched ON.

On those rare occasions when we are "in the cold," an hour or so before starting the engine I will turn ON the AquaHot's Diesel Burner switch, then 15 minutes later turn ON the Engine PreHeat switch.  An hour lead time will warm up the engine to near 100F before starting it.

[Carl Boger]

Thanks Fred and David.

On my coach the circulation pump for the hurricane only comes on when the water pump switch closest to the right is turned on.  It will start the pump whether the thermostat is turned on or off.  I have no real clue that the Engine Heat switch is actually doing.  It did light up when I would turn it to the up position, but now it doesn't.   

I had believed that it might have opened a valve in the hot water lines, loop, to help preheat the engine when it was cold. 

I am also not positive that the system was installed properly.  Really why a 12 volt on off switch for engine preheat?  Where is the switch going to and what is it turning on and off?

Usually I only need AC, but I would like everything to work as it is designed.  The heat now works after you turn on the thermostat, the Hurricane switch, and the pump switch.  The fans are controlled by a separate fan switch that has high low and off speeds.

Engine Heat is a unknown for me.  The Coach is also currently winterized so there is no water in the water heater, but the heat ex changer loop is still hooked up.   As you know space is tight and following unmarked wires is challenging.

Thanks for the help everyone, and absolutely have a great Thanksgiving! 

[David T. Richelderfer]

From reading this Forum over the years, I have learned there is a circular "loop" running from the engine forward through the coach furnace (Hurricane or AquaHot) and on to the dash heat.  There are one or two manual valves in this loop located under the bed (or under the engine access door in the bedroom floor).

When the engine is running, the loop's coolant circulation is provided by the engine's water pump.  When the engine is not running, the loop's coolant circulation is provided by a pump in the coach furnace (Hurricane or AquaHot) that is activated by turning ON the Engine PreHeat switch.  I can hear the coach furnace pump start running to push coolant through the loop when I turn ON the Engine Preheat switch.

Of course, to preheat the engine, two things are needed - heat and moving that heat to the engine.  So, turning ON the coach furnace (Hurricane or AquaHot) provides the heat and turning ON the Engine Preheat switch activates the pump to move the heat down the loop to the engine.

[Carl Boger]

Thanks for everyone's help.

I am going to chalk this one up to OPERATOR ERROR!

I have to have the furnace actually running for the Engine Light to illuminate!  On my coach at least the thermostat has to be on heat, the Hurricane system turned on and once its running the engine heat switch will work.  The hurricane pump will run with the pump switch turned on or off depending on the signal it get from the control board.

As for the manual valves under the bed, I may have the only coach that does not have them.  I'm not sure if a prior owner deleted them or if they were never installed.

Anyway the good news is everything is working properly again.   
Thanks again for everyone's help.

[Steve Huber]

Carl,
I initially couldn't find the seasonal valves on my 2000 Marquis either. I finally located them tucked away on the driver's side under the flooring near the bed. Had obviously been installed by someone a lot more flexible than me. In any case they were not at all obvious. Also found mine were labeled in reverse (summer was winter, etc).
Steve