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Topic: 'Diesel' Switch on AH Panel (Read 485 times) previous topic - next topic

'Diesel' Switch on AH Panel

Question:  Does the Diesel switch on AH panel allow the engine to heat the aqua-hot, or does it allow the AH to preheat the engine before starting?
Thanks, Mike
Mike Brady
'97 U320 SE. #5137
'13 Honda Fit
Willow Springs, MO

Re: 'Diesel' Switch on AH Panel

Reply #1 –
I am sure it uses the A Hot to pre heat engine.
JohnH
Coachless, now use aircraft. 2003 Ford Travelair TC280 class C. Super shape. Just for 1 yr .
1994 Ford E350 ClassC,total renovation inside and out. Now sold.
2000 U295  36' Cummins 350 c/w Banks Stinger, Resonator upgrade,Solar, LED lites.Residential fridge with slide out pantry. Build 5674. Sold
ex 92 GV 022C ored Cummins. Sold
ex 95 GV240 cat 3116. Sold
2017 Mini cooper s & 2016 land Rover LR2 HSE  LUX.
jhaygarth@aol.com    SKP #130098
treat everyone as you would like to be.

Re: 'Diesel' Switch on AH Panel

Reply #2 –
Quote from: Yetch –
Question:  Does the Diesel switch on AH panel allow the engine to heat the aqua-hot, or does it allow the AH to preheat the engine before starting?

There should be 3 switches; diesel, electric, and engine heat.

The diesel switch controls the diesel burner in the AquaHot.  It allows the AquaHot to burn diesel fuel to create heat/hot water.  It has nothing to do with the coach engine per se.

The electric switch allows the electric element in the AquaHot to heat up.  This will provide some heating but doesn't provide close to the BTUs that running the diesel burner does.

If both diesel and electric switches are on, the AquaHot is designed so the electric element will operate and the diesel burner will only fire up if the heating rate/boiler temperature on electric alone is insufficient.

The Engine Heat switch allows the AquaHot to preheat the coach engine IF the AquaHot is running (on either electric or diesel) and the boiler is hot.  This isn't instantaneous heating, so allow plenty of time if you need to preheat the engine (say, hours).

The coach engine heat from running (say, down the road for a few hours) does heat up the boiler fluid so you have some hot water/heat at the end of a drive day without explicitly running the AquaHot on diesel or electric.  How much heat/hot water depends on ambient temperatures, usage, etc.

HTH.
Learn every day, but especially from the experiences of others. It's cheaper!  - John C. Bogle

2000 U320 36' non-slide / WildEBeest Rescue
2003 U320

Re Engine Heat' on AH Panel

Reply #3 –
My Bad!  I meant the 'Engine Heat' switch.
Mike Brady
'97 U320 SE. #5137
'13 Honda Fit
Willow Springs, MO

Re: 'Diesel' Switch on AH Panel

Reply #4 –
Mike,

I agree with prior posts.

If it is cold enough to need engine preheat, it is to cold for the electric element to handle the demand.  You need the Diesel Burner to be on with the electric element IF you are plugged in.

Run the engine for at least one hour, two or three is better, and the engine will light right up.

If you need more info, call me 7 one 3  8 one 8  3234
Rudy Legett
2003 U320 4010 ISM 450 hp
2001 U320 4220 ISM 450 hp
1995 U320 M11 400 hp
1990 Granvilla 300 hp 3208T
Aqua Hot Service Houston and Southeast Texas

Re: 'Diesel' Switch on AH Panel

Reply #5 –
Any time it's below 40deg, I turn mine on. The colder it is, the longer I let it run. If nothing else it keeps the pump in working order.
Richard & Betty Bark & Keiko our Golden Doodle
2003 U320T 3820 PBDS
Build # 6215
MC # 16926
2016 Chevrolet Colorado 4X4 diesel

Re: 'Diesel' Switch on AH Panel

Reply #6 –
Mike, I knew you meant to say "engine heat" due to the way your comment was leaning.
JohnH
Coachless, now use aircraft. 2003 Ford Travelair TC280 class C. Super shape. Just for 1 yr .
1994 Ford E350 ClassC,total renovation inside and out. Now sold.
2000 U295  36' Cummins 350 c/w Banks Stinger, Resonator upgrade,Solar, LED lites.Residential fridge with slide out pantry. Build 5674. Sold
ex 92 GV 022C ored Cummins. Sold
ex 95 GV240 cat 3116. Sold
2017 Mini cooper s & 2016 land Rover LR2 HSE  LUX.
jhaygarth@aol.com    SKP #130098
treat everyone as you would like to be.

Re: 'Diesel' Switch on AH Panel

Reply #7 –
I believe the instructions call for turning the engine heat switch off before starting the engine. Perhaps to avoid a conflict between the engine circulating the coolant and the pump circulating the coolant? Perhaps Rudy will verify my memory.

Re: 'Diesel' Switch on AH Panel

Reply #8 –
You are right and that's what I do
Richard & Betty Bark & Keiko our Golden Doodle
2003 U320T 3820 PBDS
Build # 6215
MC # 16926
2016 Chevrolet Colorado 4X4 diesel

Re: 'Diesel' Switch on AH Panel

Reply #9 –
I am 'full-timing' every other week in the Midwest, and I am leaving both diesel and electric on all the time,  as the coach needs to be comfortably heated; seems to be working pretty good(knock on wood).  On fridays, I head home, and it will be below freezing, so the plan is to turn the engine heat on Thursday night to be ready for an engine start Friday morn.
Mike
Mike Brady
'97 U320 SE. #5137
'13 Honda Fit
Willow Springs, MO

Re: 'Diesel' Switch on AH Panel

Reply #10 –
Properly installed engine coolant lines at the heater flow in the same direction as does the engine preheat pump.  So It does not matter whether the pump is running or not when the engine is running.  BUT, there is no reason to believe the assembly person knows which line is from the engine and which line is back to the engine.

SO, the best policy is to turn pump off before starting engine.

Running the engine preheat for a minimum of one hour will usually get the engine to start.  Two to three hours is better.  Over night for hours is overkill.  But that does not hurt anything.  Just uses more heat energy from heater coolant than needed.
Rudy Legett
2003 U320 4010 ISM 450 hp
2001 U320 4220 ISM 450 hp
1995 U320 M11 400 hp
1990 Granvilla 300 hp 3208T
Aqua Hot Service Houston and Southeast Texas