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Topic: Cummins heating Aquahot loop while driving (Read 616 times) previous topic - next topic

Cummins heating Aquahot loop while driving

While driving and wanting the Cummins to heat the aquahot loops, does the AH switch that is used to preheat the cummins when parked need to be on?

Never thought about it before.
Dan - Full timing since 2009
2003 U320 40' Tag 2 slide

Re: Cummins heating Aquahot loop while driving

Reply #1 –
No, it does not
Frank & Daisy
NO LONGER  "looking for the perfect Foretravel
36' or less non slide preferred."  She has been found and is ours.
2003 U320 36' non slide  Unit 6103
Cummins ISM 450
Allison 4000MH

Re: Cummins heating Aquahot loop while driving

Reply #2 –
Completed a 135 mile drive today. Pulled into campground.  AH diesel burner kicked on immediately after parking  (diesel switch was on). 

AH loops should have been fully hot from the 135 mile drive.
Dan - Full timing since 2009
2003 U320 40' Tag 2 slide

Re: Cummins heating Aquahot loop while driving

Reply #3 –
My experience is that driving heats the AH tank up to about 145-150°. Enough for hot water for most uses after a day of driving.  If you want hotter it needs to have the electric or diesel on  The diesel can be on while you drive.

Adding a temp sensor and display gives you a lot of information about how the AH works.  My temp displays come on when the water pump is on.  Red is the AH tank, blue is at the manifold.
Roger Engdahl and Susan Green
2001 U320 3610 #5879 (Home2) - 2014 Jeep Cherokee or 2018 F150
Hastings, MN

Re: Cummins heating Aquahot loop while driving

Reply #4 –
The engine preheat switch should be off at all times except for when you want to start a cold engine in frigid conditions.

The engine preheat loop will, as Roger noted, heat the coolant.  This will heat the interior to 70+ down to 50, maybe 45 degrees outside.  But it does not have the capacity of the 50k btu diesel burner.  So, when traveling in freezing conditions, turn on the diesel burner to supplement the preheat loop to keep the interior at 70+ degrees.
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: Cummins heating Aquahot loop while driving

Reply #5 –
When I had my Monaco Dynasty I put a couple of heaters in the back of the coach
would keep the coach HOT inside well below 0 fahrenheit outside. I guess the
Aqua-hots heat exchanger isn't isn't that efficient. In the summer won't the Aqua-
hot water temperature reach engine temperature and if not why.
Peter and Frieda Morin
1999 36ft. U320 Foretravel
Build # 5436
1998 Suzuki Sidekick Sport

Re: Cummins heating Aquahot loop while driving

Reply #6 –
Quote from: Rudy –
The engine preheat switch should be off at all times except for when you want to start a cold engine in frigid conditions.

The engine preheat loop will, as Roger noted, heat the coolant.  This will heat the interior to 70+ down to 50, maybe 45 degrees outside.  But it does not have the capacity of the 50k btu diesel burner.  So, when traveling in freezing conditions, turn on the diesel burner to supplement the preheat loop to keep the interior at 70+ degrees.

We are now right at the TX/OK border at Lake Texoma.  Had the electric and diesel switches on from our start in Chickasha  OK at 44 degree morning.  I "think" I had front thermostat set at 70 and back at 63.  Warm outside on arrival at 1:30.

I'll pay more attention to thermostats and outside temp on on our next move on 14 Nov.

Arriving in Lake Texoma and parked, suprised the burner kicked on (no gen run on drive).  But sounds like all is operating normally.
Dan - Full timing since 2009
2003 U320 40' Tag 2 slide

Re: Cummins heating Aquahot loop while driving

Reply #7 –
Quote from: Lt403 –
No, it does not

Learn something new everyday. I thought that it did need to be on in order for the coolant from the engine to reach the aqua hot. So during the day when I'm driving I do have that switch on and have hot water when I get to where I'm going. I will attempt it the next time without the switch on and see if there's a difference. So the engine then pumps the water through the aqua Hot loop without the aqua hot pump circuit on?
'99 U320 40 WTFE
Build #5462,
1500 Watts Solar 600 amp Victron lithium
2012 Jeep Grand Cherokee Overland Hemi
Instagram bobfnbw
Retired

Re: Cummins heating Aquahot loop while driving

Reply #8 –
Quote from: Journey, Roam, Explore –
Learn something new everyday. I thought that it did need to be on in order for the coolant from the engine to reach the aqua hot. So during the day when I'm driving I do have that switch on and have hot water when I get to where I'm going. I will attempt it the next time without the switch on and see if there's a difference. So the engine then pumps the water through the aqua Hot loop without the aqua hot pump circuit on?

The engine water pump does the circulating when driving. Same as the non Aqua Hot coaches with the same loop.
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean