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Topic: AQUAHOT (COZY HEAT EXCHANGER) WONT COME ON FOR ZONE 1 AND 2 (Read 737 times) previous topic - next topic

AQUAHOT (COZY HEAT EXCHANGER) WONT COME ON FOR ZONE 1 AND 2

I need help with my heating zones, I have the aquahot and inside I have 3 zones for heat and 3 acs on roof, So this happened last year already and I cant seem to find the problem, last winter I used jumper wires on the aquahot to get zone 1 and 2 to work, I jumped them from zone 3, What does not work is zone 1 and zone 2 on the heat side of aquahot only, The ac zones all work in cool and on the heat pumps, Zone 3 works on the aquahot for heat. I have chased wires and grounds, I thought maybe it was the control board on the ACs  front and middle but replaced front ac board with a spare and same issue so I am rethinking that the boards may be bad, any help would be greatly appreciated, I understand that the thermo zones are ground but the cozy heat fans require  power at same time the thermo kicks the aquahot relays on so is my issue a relay for each of the zones bad?  Again any help would be greatly appreciated.
Adam Byler
1999 U320 M4200 DGFE Build #5389
2014 Sundowner 26 ft Enclosed
2015 Ford F150 King Ranch crew cab

Re: AQUAHOT (COZY HEAT EXCHANGER) WONT COME ON FOR ZONE 1 AND 2

Reply #1
On your thermostat what are you using to call for heat on zone 1 & 2? Do you have it calling for furnace not heat pumps?
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

Re: AQUAHOT (COZY HEAT EXCHANGER) WONT COME ON FOR ZONE 1 AND 2

Reply #2
Yes the furnace side of zone 1 and 2 does not turn the aquahot on or the cozy heat exchangers, zone 3 works in the bedroom only
Adam Byler
1999 U320 M4200 DGFE Build #5389
2014 Sundowner 26 ft Enclosed
2015 Ford F150 King Ranch crew cab

Re: AQUAHOT (COZY HEAT EXCHANGER) WONT COME ON FOR ZONE 1 AND 2

Reply #3
The heat pumps work as does the ac on all zones
Adam Byler
1999 U320 M4200 DGFE Build #5389
2014 Sundowner 26 ft Enclosed
2015 Ford F150 King Ranch crew cab

Re: AQUAHOT (COZY HEAT EXCHANGER) WONT COME ON FOR ZONE 1 AND 2

Reply #4
I had a similar problem and it turned out I had the zones set on auto which I had to turn off.
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

Re: AQUAHOT (COZY HEAT EXCHANGER) WONT COME ON FOR ZONE 1 AND 2

Reply #5
On mine when you put thermo on furnace the auto option doesnt show up on the display, it only shows in cool and heat pump mode
Adam Byler
1999 U320 M4200 DGFE Build #5389
2014 Sundowner 26 ft Enclosed
2015 Ford F150 King Ranch crew cab

Re: AQUAHOT (COZY HEAT EXCHANGER) WONT COME ON FOR ZONE 1 AND 2

Reply #6
No heat pumps on mine, but an option to change furnace to Aqua Hot.
Maybe Rudy will chime in as Aqua Hot is his business.
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

Re: AQUAHOT (COZY HEAT EXCHANGER) WONT COME ON FOR ZONE 1 AND 2

Reply #7
I may be overthinking, but are the contact relays for zone 1 & 2 (a) pulling into contact without jumpering the wires, (b) are the wires on those contacts hooked up properly. When I rebuilt my AH this spring, the fans on zones 1 & 2 wouldn't shut off unless I took the relays out. Turns out, I had put one of the wires on the wrong terminal by mistake. Just guessing, but maybe a thought.

Larry
Larry Warren
1996  U320 36' SBID "Lola" sold 2020
Build #4970
Motorcade #18318

Re: AQUAHOT (COZY HEAT EXCHANGER) WONT COME ON FOR ZONE 1 AND 2

Reply #8
Larry i do not think that the wires are connected wrong as when I put jumper wire on it all works as it should other then the temp control is whatever is registered from the bedroom temp. I  am totally stumped, looked at all the wiring diagrams and cant find issue. in my opinion it would have to be a ground issue or a relay but am clueless at this point, like i said I have been chasing this gremlin for a year now so need advise from the pros,
Adam Byler
1999 U320 M4200 DGFE Build #5389
2014 Sundowner 26 ft Enclosed
2015 Ford F150 King Ranch crew cab

Re: AQUAHOT (COZY HEAT EXCHANGER) WONT COME ON FOR ZONE 1 AND 2

Reply #9
Adam,  Been busy today and fixed a heater too.

Now, if you have placed a ground jumper on the terminals on the top of the heater marked Living Room, Bathroom, Bedroom and the fan coils have produced warm air, then the Aqua Hot is fine.  As you have suggested, there is a dip switch on the front A/C that allows the inside room thermostat to talk to the heater.  Sounds to me that the stat is not talking to the heater.

So, suggestion is to verify the A/C board dip switch is in the proper position.  Sorry to be of so little help.
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: AQUAHOT (COZY HEAT EXCHANGER) WONT COME ON FOR ZONE 1 AND 2

Reply #10
Can you get the thermostat to show furnace on all 3 zones? If not then it could be the dip switches on zone 2 and 3 circuit boards
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 (COZY HEAT EXCHANGER) WONT COME ON FOR ZONE 1 AND 2

Reply #11
Thanks for the suggestions, Yes the thermostat shows the furnace zones
Adam Byler
1999 U320 M4200 DGFE Build #5389
2014 Sundowner 26 ft Enclosed
2015 Ford F150 King Ranch crew cab

Re: AQUAHOT (COZY HEAT EXCHANGER) WONT COME ON FOR ZONE 1 AND 2

Reply #12
I might suggest you do a reset on your thermostate.  You need to push in Mode & Zone buttons, hold them in and then turn the on off switch back on and this does the reset and see if the zones don't work then.  I had to do this when it failed to allow heat pumps to work again.  Like Rudy suggested, you need to check your dip switches and make sure they are in the correct selection.
Joe & Dottie Allen
Sold!  December 2023.      2000 U320; build # 5645
Our coach " Maxine"
Motorcade #  15922;  Escapee 150950; FMCA F330833; Boondockers Welcome;  Harvest Hosts;  Thousand Trails
'98 U320 from 2000-'06
USAF '62-'66

"Do not spoil what you have by desiring what you have not; remember that what you now have was once among the things you only hoped for." ―Epicurus

Re: AQUAHOT (COZY HEAT EXCHANGER) WONT COME ON FOR ZONE 1 AND 2

Reply #13
I finally figured out it was 2 new relays that I replaced when this all started, replaced them again and all works, I never had this happen before and dont know why 2 relays would be bad. Thanks Adam
Adam Byler
1999 U320 M4200 DGFE Build #5389
2014 Sundowner 26 ft Enclosed
2015 Ford F150 King Ranch crew cab

Re: AQUAHOT (COZY HEAT EXCHANGER) WONT COME ON FOR ZONE 1 AND 2

Reply #14
Not all relays are created equal. /Did you check to see if the contacts were jumping the same terminals?
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