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Topic: Aquahot for coach heat (Read 857 times) previous topic - next topic

Aquahot for coach heat

I have a 2000 U320 that has aqua hot. I know  there is a thermostat in the Bathroom to supply heat there. I was told by 2 very knowledgeable guys here on the forum that to supply heat to the bedroom and living area that I needed to set the living room thermostat to "furnace" and that would use the aquahot system for heat. Not being at my coach at the time I told them that I didn't recall the thermostat having a "furnace" mode. Well today I went to the coach to investigate this and I was right, there was no furnace setting, only off,fan,cool and heat pump. The coach has floor registers like it has the ability... anyone have any idea why the furnace setting is not on the thermostat? It is  a Dometic 2 zone thermostat just like the one in the coach of one of the guys I talked to..

Keith
The selected media item is not currently available.Keith & Jo
2003 U320T 4025 PBBS Designer series
Build 6203    Cummins 500hp
2000 U320 4010 WTFE / Build 5762 —Sold—
Motorcade #18070   
Pasadena, Texas
2015 Jeep Wrangler Sahara-Sunset Orange pearl coat
Don't argue with a fool, people watching might not be able to tell the difference.

Re: Aquahot for coach heat

Reply #1 –
Sounds like the dip switches on the A/C control board are not set correct.
Has the front A/C  unit been worked on lately or change out from OEM?

Mike
Pamela & Mike 97 U 320

"It's not what happens to you, but how you react to it that matters."

Re: Aquahot for coach heat

Reply #2 –
I have had the coach for a year and a half and they are original ac's as far as I know and I have had no work done to them.. I'll have to check my paperwork, seems like I remember on the pdi paperwork that the thermostat was changed..  are the dip switches in it?  Keep in mind there's a dip switch on this side of the thermostat making the changes.....

Keith
The selected media item is not currently available.Keith & Jo
2003 U320T 4025 PBBS Designer series
Build 6203    Cummins 500hp
2000 U320 4010 WTFE / Build 5762 —Sold—
Motorcade #18070   
Pasadena, Texas
2015 Jeep Wrangler Sahara-Sunset Orange pearl coat
Don't argue with a fool, people watching might not be able to tell the difference.

Re: Aquahot for coach heat

Reply #3 –
You should have two zones. Is there no furnace mode in either one?
Have you tried a reset?

Re: Aquahot for coach heat

Reply #4 –
Quote from: hdff –
thermostat was changed..  are the dip switches in it? 

Keith,
No the dip switches I was referring to are in the A/C units on the roof.  On the PC board is a set of (IIRC) 5 dip switches that causes the A/C units to talk to each other along with the Aqua Hot unit.

If the thermostat on the wall has been changed out it may not know that you have a Aqua Hot unit along with a heat strips/heat pump in the A/C unit.
Mike
Pamela & Mike 97 U 320

"It's not what happens to you, but how you react to it that matters."

Re: Aquahot for coach heat

Reply #5 –
2 zones and no furnace on either zone. How do I reset it??
If it doesn't know can I have this changed??
Keith
The selected media item is not currently available.Keith & Jo
2003 U320T 4025 PBBS Designer series
Build 6203    Cummins 500hp
2000 U320 4010 WTFE / Build 5762 —Sold—
Motorcade #18070   
Pasadena, Texas
2015 Jeep Wrangler Sahara-Sunset Orange pearl coat
Don't argue with a fool, people watching might not be able to tell the difference.

Re: Aquahot for coach heat

Reply #6 –
Quote from: hdff –
If it doesn't know can I have this changed??

If the new thermostat is same as the old one it should have been a direct swap out. If it is one of the new Comfort Control thermostats then it will have to be set up with there spec. sheets. I don't have the info as to how to set up the CC system to the OEM HVAC system.

Mike
Pamela & Mike 97 U 320

"It's not what happens to you, but how you react to it that matters."

Re: Aquahot for coach heat

Reply #7 –
Here is a picture of the dip switch panel inside my air conditioner unit.... hope this helps at least identify it

Mike & Joanne
'99  U320  40' build 5479
'06 Lexus GX470
Club #17378
(former '93 U225 36')

Re: Aquahot for coach heat

Reply #8 –
Quote from: Mike & Joanne Whitaker –
Here is a picture of the dip switch panel inside my air conditioner unit.... hope this helps at least identify it


so where exactly do I find this? on the ac? inside or outside? or in the thermostat?
The selected media item is not currently available.Keith & Jo
2003 U320T 4025 PBBS Designer series
Build 6203    Cummins 500hp
2000 U320 4010 WTFE / Build 5762 —Sold—
Motorcade #18070   
Pasadena, Texas
2015 Jeep Wrangler Sahara-Sunset Orange pearl coat
Don't argue with a fool, people watching might not be able to tell the difference.

Re: Aquahot for coach heat

Reply #9 –
The boards are on top remove the plastic cover then on passenger side of the coach there is a small metal cover about 6 inches square held down with 2 hex head screws. Remove the cover and the circuit board will be there. Make sure there is no shore cord or generator running as you don't want to get shocked.
previous 1984 35 ft ORED 250 HP 3208 Cat       
previous 1998 40 ft U295 CAI 325 hp Cummins
previous 2003 40 Ft u320 build #6140 450 Cummins M11.                                                         
1999 Mazda Miata
Ron, Nancy, Tipper the cat, Max The dog
1997 U 270 36 ft build number 5174 8.3 Cummins

Re: Aquahot for coach heat

Reply #10 –
It has been awhile since I took this picture, but I believe red tractor has described it properly. I recall it was under the main cover of the ac unit (on the roof) and it is under another cover inside of that.
Mike & Joanne
'99  U320  40' build 5479
'06 Lexus GX470
Club #17378
(former '93 U225 36')

Re: Aquahot for coach heat

Reply #11 –
Follow up. Thanks Mike, travelin man, Mike and Red Tractor... the problem was the dip switches. Tried to reset the thermostat, no luck.  Climbed on the roof this evening after work and checked the ac's, both had the furnace switch in the off position. Now thermostat has furnace option on both zones. Ran the aquahot and could only get air flow out of the dash vents...🤷‍♂️ Did some investigating and found these ground wires not attached to a ground post on the aqua hot... why I have no idea... I touched them to the post and the floor registers started blowing. Disconnected it until I talked to an expert to make sure my thoughts were right and I wasn't screwing something up. Will go connect them tomorrow. Here is a pic of the loose green wires with lugs and ground post, apparently the green wires are great ground wires for the floor register fans...
The selected media item is not currently available.Keith & Jo
2003 U320T 4025 PBBS Designer series
Build 6203    Cummins 500hp
2000 U320 4010 WTFE / Build 5762 —Sold—
Motorcade #18070   
Pasadena, Texas
2015 Jeep Wrangler Sahara-Sunset Orange pearl coat
Don't argue with a fool, people watching might not be able to tell the difference.

Re: Aquahot for coach heat

Reply #12 –
I had the same problem after the guys on the west side of the highway "fixed" my AH for more than $1K.  Didn't need a new control box, they never did a service, it was the coil all the time.  John Carrillo up in Denver fixed it.  Got my money back from the other guys. And they left the nut off the ground terminal and eventually the wires came off.

Some wiring detail too.


We have been using our AH all the time since we got to TX, colder than normal they tell us, pretty much shorts weather to me.  If the temps get below 40 we turn on the dieselotherwise we are fine with electric when we have it. We turn down the LR at night, heats us quick in the AM. 

I had some noisy bearings in the blower. Best guy Rudy helped get them changed out.  Thanks good friend!
Roger Engdahl and Susan Green
2001 U320 3610 #5879 (Home2) - 2014 Jeep Cherokee or 2018 F150
Hastings, MN

Re: Aquahot for coach heat

Reply #13 –
Final follow up..... attached the 2ground wire bundles and everything seems to be working as it should.... thanks for the input everyone..

Keith
The selected media item is not currently available.Keith & Jo
2003 U320T 4025 PBBS Designer series
Build 6203    Cummins 500hp
2000 U320 4010 WTFE / Build 5762 —Sold—
Motorcade #18070   
Pasadena, Texas
2015 Jeep Wrangler Sahara-Sunset Orange pearl coat
Don't argue with a fool, people watching might not be able to tell the difference.