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Topic: Aqua Hot Living Room Zone | Dash Defrost Vents Blowing Cold Air (Read 1006 times) previous topic - next topic

Aqua Hot Living Room Zone | Dash Defrost Vents Blowing Cold Air

See "Dash A/C Condenser Fan Wiring" for background.

Also had Redlands Truck & RV, Redlands CA work on my Aqua Hot.  The AQ needed a new electric element so had them replace the burned out one with an upgraded 2000W unit.  The repairs required the boiler coolant be drained.  While they were changing out the electric element had them repair the tempering valve which was corroded.  I talked to the technician concerning priming the pumps after he refilled the AQ tank.  Sounded like he did it correctly.  Pretty sure he didn't check to see if the heating zones were actually working since the temps in Redlands at the time were in the upper 90s to low 100s.  Unfortunately, I think the dash A/C technician screwed up the front AQ zone.  Today we are in the Flagstaff AZ area and it is in the low 60s.  Good time to test the AQ heating zones.  Bedroom zone good heat; bathroom zone good heat; living room/galley zone not good.  Had warm air in the galley, luke warm air in the living room and cold air from the dash defrost vents.    Checked the pump for the LR/galley zone and it was warm, but the return line was cold so no boiler fluid is circulating.  Talked to Rudy and he said the zone line either has a kinked hose or the A/C tech disconnected the AQ dash register.  What to do?  How difficult is it to take apart the dash facade so I can verify that the heating core and AQ cores are connected to their hoses?  Any other suggestions would be greatly appreciated.
David & Sherry Kendrick
"Gizmo" The Doggy Lama
USAF(Ret) 1971-75; 1979-95 (20 yrs)
2003 U320 F03 [6179] 38PBDS (3/2016)
2016 Chev Silverado Z71 LTZ
Motorcade 17738
--------------------------------------
New Horizons 5W 25' RKS (1/2004 - 3/2016)
2003 Chev Silverado 2500HD Duramax
Tent (5-person) White Stag (1972 - 2003)

Re: Aqua Hot Living Room Zone | Dash Defrost Vents Blowing Cold Air

Reply #1 –
If the hoses weren't connected you would have a major leak up front. Was Rudy sure that the pump was primed for that loop. Anytime the coolant is drained air lock is a possibility.
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: Aqua Hot Living Room Zone | Dash Defrost Vents Blowing Cold Air

Reply #2 –
The pump discharge line was warm, but the return was not.  There was heat from the galley register and half way heat from the living room register under the console table, but no heat from the dash defrost vents.
David & Sherry Kendrick
"Gizmo" The Doggy Lama
USAF(Ret) 1971-75; 1979-95 (20 yrs)
2003 U320 F03 [6179] 38PBDS (3/2016)
2016 Chev Silverado Z71 LTZ
Motorcade 17738
--------------------------------------
New Horizons 5W 25' RKS (1/2004 - 3/2016)
2003 Chev Silverado 2500HD Duramax
Tent (5-person) White Stag (1972 - 2003)

Re: Aqua Hot Living Room Zone | Dash Defrost Vents Blowing Cold Air

Reply #3 –
Turn the ignition on and see if it gets heat. The wires could be crossed that control the flapper that switches from Aqua Hot to engine heat.
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: Aqua Hot Living Room Zone | Dash Defrost Vents Blowing Cold Air

Reply #4 –
Quote from: WagonWheels –
  Checked the pump for the LR/galley zone and it was warm, but the return line was cold so no boiler fluid is circulating.

Are you sure that the pump is running not just warm from residual heat in the piping?
The check valve for that zone may be stuck and not opening fully.  Give it a tap to see if it will jar loose.

Mike
Pamela & Mike 97 U 320

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

Re: Aqua Hot Living Room Zone | Dash Defrost Vents Blowing Cold Air

Reply #5 –
Did your tech do anything inside the coach?  or under the dash?  If not then nothing should have changed with those registers or hoses.
I'm also thinking it is either not purged or a check valve is stuck.
Forest & Cindy Olivier
1987 log cabin
2011 Roadtrek C210P
no longer 1999 36' U320 build #5522
2013 Rzr 570 & 2018 Ranger XP1000
2006 Lexus GX470
2011 Tahoe LT 4x4
Previous 1998 45' 2 slide Newell, 1993 39' Newell

Re: Aqua Hot Living Room Zone | Dash Defrost Vents Blowing Cold Air

Reply #6 –
Here is what I understand about his situation.  The Aqua Hot heater tank was drained which requires the priming of the three zone pumps.  The tech did prime the zone pumps.  The front zone is in question so if it did not prime no hot coolant would be above the pump.  He reports the pipe above the pump is hot but not the retrun line.  He reports warm air from kitchen fan coil also.  So some movement of hot coolant but no circulation.

He states the dash A/C was worked on which is where the cool air is being reported.  The same fan blows air for dash A/C or dash heat as well as Aqua Hot heat.  The AH heating coil is right there where the A/C work was preformed.  So opening the dash to observe the AH heater hoses to the AH coil is what I suggested.

Wish I could be there as it would not take long to narrow the problem down when I can put hands on the situation.  I helped a local owner serivice his heater over the phone.  It would not fire back up with new nozzle and new coil.  He was close by so I drove over and in five minutes found he had badly miss adjusted the ignition points.  So eyes on solved it quickly.

All the best solving this.
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: Aqua Hot Living Room Zone | Dash Defrost Vents Blowing Cold Air

Reply #7 –
 David; check this:  open up the AH and if yours is like mine, you will have a little wire holding each zone in place on the right side of the AH.  I found one off and when I pushed on the zone that the wire holds in place, it was loose and then the zone worked.  Hope this makes sense, as Rudy suggested this and that was it.  Good to go!  You will see the little thin wire that snaps over these units, as I believe there are 3 side by side for what I remember.  Hope this solves your issues!  I believe that you have the same AH as we do.
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: Aqua Hot Living Room Zone | Dash Defrost Vents Blowing Cold Air

Reply #8 –
This is a silly question but how long did you wait for heat?  I find that the kitchen and living room heat exchangers soak up all the heat for a few minutes before the front starts putting out hot air.

Re: Aqua Hot Living Room Zone | Dash Defrost Vents Blowing Cold Air

Reply #9 –
On Saturday while in Flagstaff AZ I began disassembling the dash facade in an effort to see what the Aqua Hot hoses looked like.  The facade came off rather easily.  Probably be a lot harder to put back together.  I turned on the AQ Zone 1 (Galley/Living Room since it was cool enough to get heat.  Had heat in the galley, some out of the living room register and none out of the dash defrost vent.  Fans were running in all three locations. Turned off the AQ and turned on the dash heater and switched it to the defrost setting.  The fan came on.  Stuck my hand down the dash defrost vent to feel where the air was blowing from.  Sure enough there were two squirrel cages and one of them nearly cut off the end of one of my fingers.  How dumb is that!! The next day, Sunday was a travel day to Nellis AFB, Las Vegas NV.  After we arrived I poked (with bandaged finger) around in the innards of the dash looking for hoses.  Located three sets of hoses, dash A/C, engine coolant hose to dash heater, and AQ hoses for the zone 1 heat.  I can identify the dash A/C hoses, but not the the other four.  Guess I could turn on the coach engine and warm it up and check temperature of the four hoses to identify the heater hoses.  I did locate a valve on one of the unidentified hoses (see picture).  BTW  all three sets of hoses go into a box which I assume contains the heat/cooling exchangers.  Any idea what the valve controls?  If it is on the AQ line and having the valve closed off would prevent heated boiler coolant from circulating through the AQ heat exchanger.  I also crawled under the front of the coach and looked at the hoses that emerge from the chase and make their way through the floor.  Nothing looked out of the ordinary, just dusty.  There is a control valve with wiring on one of the hoses.  Today I had my 6-month eye exam for glaucoma so haven't accomplished much.  We extended our stay from 2-nights to 4-nights so we can put the dash back together.  Had to re-glue a lot of the velcro strips and apoxy some cracks around holes in the dash facade.
David & Sherry Kendrick
"Gizmo" The Doggy Lama
USAF(Ret) 1971-75; 1979-95 (20 yrs)
2003 U320 F03 [6179] 38PBDS (3/2016)
2016 Chev Silverado Z71 LTZ
Motorcade 17738
--------------------------------------
New Horizons 5W 25' RKS (1/2004 - 3/2016)
2003 Chev Silverado 2500HD Duramax
Tent (5-person) White Stag (1972 - 2003)

Re: Aqua Hot Living Room Zone | Dash Defrost Vents Blowing Cold Air

Reply #10 –
Does that valve have a terminal at the top. If so look for the missing wire. If it has a nipple look for the vacuum line.
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: Aqua Hot Living Room Zone | Dash Defrost Vents Blowing Cold Air

Reply #11 –
The valve in the picture is located in the dash near where all the hoses (A/C, heater, AQ) inter the heat exchanger box.  The valve appears to be mechanical, there are no electric wires attached to it.
David & Sherry Kendrick
"Gizmo" The Doggy Lama
USAF(Ret) 1971-75; 1979-95 (20 yrs)
2003 U320 F03 [6179] 38PBDS (3/2016)
2016 Chev Silverado Z71 LTZ
Motorcade 17738
--------------------------------------
New Horizons 5W 25' RKS (1/2004 - 3/2016)
2003 Chev Silverado 2500HD Duramax
Tent (5-person) White Stag (1972 - 2003)

Re: Aqua Hot Living Room Zone | Dash Defrost Vents Blowing Cold Air

Reply #12 –
Looks like someone used a pair of pliers or something on it from the picture of it.
Future Foretravel Owners
2019 Jeep Cherokee Trailhawk
Retired USAF, Retired DOD Civ's
FAA A&P, Indust. Eng., Acft Depot Lvl. Maint.
Larry and Becky Rountree

Re: Aqua Hot Living Room Zone | Dash Defrost Vents Blowing Cold Air

Reply #13 –
I have in mind the heater valve from the engine was outside underneath by the generator on the passenger side in our 2002 and had an electric wire going to it.  I haven't needed to find it on our 2003. 
Rick & Rhonda
2003 U320 4220  Build #6199
Was
91 36' GV 300 Caterpillar, 92 40' U280 300 Cummins, 97 36' U295 300 Cummins, 2002
U320 450 Cummins
(Guess we're hooked)

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Re: Aqua Hot Living Room Zone | Dash Defrost Vents Blowing Cold Air

Reply #14 –
David,

As Rick said, the heater hose "H" valve is likely the one you saw beneath the front end.  Early in my ownership of my coach I had to replace that valve because it became frozen.  It was not a difficult or expensive repair. 

Of course those are not the hoses that are your issue, but if you can follow those lines up into the inside of the coach you can eliminate them as the AquaHot lines. 

Richard
Jan & Richard Witt
1999 U-320  36ft WTFE
Build Number: 5478 Motorcade: 16599
2011 Jeep Wrangler Unlimited w/Air Force One
Jan: NO5U, Richard:KA5RIW
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Re: Aqua Hot Living Room Zone | Dash Defrost Vents Blowing Cold Air

Reply #15 –
Take a look at the AQ wiring panel and let me know if something is amiss.  I texted Redlands Truck and asked the service advisor if the A/C mechanic had turned off the pictured valve.  The SA claims the mechanic didn't turn off the valve.  He asked me what the problem was.  I had told him what the problem was in a telephone call a couple days ago, so text him with the details today.  Hopefully he can remember.

I located the electric valve under the front end of the coach near the genset.  I presume this valve controls the engine coolant that reaches the heater register when one turns the dash heat dial. 

I have a call into FOT tech support asking for a heater/AQ/A/C hose schematic.  I may just fire up the engine and check the hoses to see which ones are warm/hot to discern heater hose from AQ hose.
David & Sherry Kendrick
"Gizmo" The Doggy Lama
USAF(Ret) 1971-75; 1979-95 (20 yrs)
2003 U320 F03 [6179] 38PBDS (3/2016)
2016 Chev Silverado Z71 LTZ
Motorcade 17738
--------------------------------------
New Horizons 5W 25' RKS (1/2004 - 3/2016)
2003 Chev Silverado 2500HD Duramax
Tent (5-person) White Stag (1972 - 2003)

Re: Aqua Hot Living Room Zone | Dash Defrost Vents Blowing Cold Air

Reply #16 –
Well I got tired of waiting on Rudy and/or FOT tech support getting back to me.  I'm sure they are busy getting ready for the hurricane.  Anyway, I turned on the Aqua Hot furnace and set the thermostat to 95 on the galley/living room zone.  Heat came on despite being parked in Las Vegas.  Warm air in galley, not as warm air out the living room register and cold air out the center defrost dash vent.  Felt the hoses under the dash and found one that was getting hot.  It was one of the pair with the funking looking valve.  The hose with the valve was still cold.  Turned the valve stem a quarter turn with a small Crescent wrench and the hose began to warm up.  Yea!!  But hold on Sparky, the valve started to bubble out through the sidewall of the stem.  Yikes, I thought maybe I was going to have boiler coolant running out under the dash.  I turned the valve off.  The hose with the valve was now just as hot as the inlet hose and warm air was coming out of the dash vent.  There are a couple of possibilities:  1)  the valve is a air purge valve and let out the air that was blocking the boiler coolant from circulating or 2) the valve needs to be turned on, but is defective.  I'm hoping for number 1.  See attached crude drawing.  About 15 minutes after my test, Ricky from FOT tech support called and told me he had placed an order with FOT engineering to get a schematic copy of the AQ/a/c/heater hoses.  It might be a couple of days because of the weather.
David & Sherry Kendrick
"Gizmo" The Doggy Lama
USAF(Ret) 1971-75; 1979-95 (20 yrs)
2003 U320 F03 [6179] 38PBDS (3/2016)
2016 Chev Silverado Z71 LTZ
Motorcade 17738
--------------------------------------
New Horizons 5W 25' RKS (1/2004 - 3/2016)
2003 Chev Silverado 2500HD Duramax
Tent (5-person) White Stag (1972 - 2003)

Re: Aqua Hot Living Room Zone | Dash Defrost Vents Blowing Cold Air

Reply #17 –
David,  We are indeed out of the area that might be affected by Laura.

The leaky valve is a Foretravel installed device.  With the heater off and cooled down, crack the radiator cap on the top of the heater to release any pressure, then retighten the cap.  Now you can remove the valve and connect the hoses together or you can replace the valve with a ball valve.

The valve might just bypass the the dash coil but your comments of the return line not getting warm tend to say the valve stops the flow of coolant through the front loop.  That would affect the other fan coils in the front loop giving poor heating.

Connecting the hoses or leaving the valve open would provide good heating to the front zone.  If you do not want warm air from the defroster vents, install a switch in the wires going to the fan to stop air flow but allowing the front zone to have good coolant flow.

Very happy to see you sorting this out, good job.

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: Aqua Hot Living Room Zone | Dash Defrost Vents Blowing Cold Air

Reply #18 –
Well I turned the valve stem a quarter turn which caused bubbling of air and coolant.  I turned the valve stem off and presto I have heat coming from the dash defroster vents.  Yea!! Checked for leaks around the valve.  No leaks.  We are currently in Pocatello ID and have had several very cool mornings (40s) and everything seems to be working like it should.  Hope it keeps working since we will be in West Yellowstone next week where they expect morning lows in the teens!!
David & Sherry Kendrick
"Gizmo" The Doggy Lama
USAF(Ret) 1971-75; 1979-95 (20 yrs)
2003 U320 F03 [6179] 38PBDS (3/2016)
2016 Chev Silverado Z71 LTZ
Motorcade 17738
--------------------------------------
New Horizons 5W 25' RKS (1/2004 - 3/2016)
2003 Chev Silverado 2500HD Duramax
Tent (5-person) White Stag (1972 - 2003)