Foretravel Owners' Forum

Foretravel Motorhome Forums => Foretravel Tech Talk => Topic started by: Caflashbob on August 11, 2020, 07:45:17 pm

Title: Dash aqua hot?
Post by: Caflashbob on August 11, 2020, 07:45:17 pm
When looking through the coaches wiring diagrams I ran across a aqua hot to dash a/c wiring drawing. 

Does this coach have the ability to run aqua hot heated antifreeze to the dash a/c system?

I thought the aqua hot was separated from the engines antifreeze?

Unless the dash heat is from the aqua hot loop? Zone one?  Or..... Not the motors antifreeze?

Title: Re: Dash aqua hot?
Post by: trailertrashrick on August 11, 2020, 07:51:35 pm
When looking through the coaches wiring diagrams I ran across a aqua hot to dash a/c wiring drawing. 

Does this coach have the ability to run aqua hot heated antifreeze to the dash a/c system?

I thought the aqua hot was separated from the engines antifreeze?

Unless the dash heat is from the aqua hot loop? Zone one?  Or..... Not the motors antifreeze?
When my front zone Aqua Hot comes on in the morning, I can hear a heat exchanger in the dash area running.  I've not gone and looked for it, but I don't think it's related to the "dash heat" from the chassis dashboard HVAC system.  I think it's Aqua Hot.  No coolant mingling.

My coolants are different colors and stay that way (so far).
Title: Re: Dash aqua hot?
Post by: craneman on August 11, 2020, 08:03:47 pm
The Aqua Hot on my coach can heat the engine, must be some coolant mingling there unless there is a separate loop in the AH for that.
Title: Re: Dash aqua hot?
Post by: turbojack on August 11, 2020, 08:10:50 pm
On the IH45 when the heat from zone 1 comes on it blows heat through the dash ac vents
Title: Re: Dash aqua hot?
Post by: Roger & Susan in Home2 on August 11, 2020, 08:16:44 pm
In my 2001 there is an AH heat exchanger in the dash, the dash blower moves air through it and out the defrost vents to heat that part of the coach.  This is on the LR loop.  The engine heat loop can pump hot coolant (shared by the engine) through the engine. While driving the engine pushes coolant through the same loop to heat water. 

In 2002 or 2003 they switched the AH to a different type of coolant.  I am not sure how these work.
Title: Re: Dash aqua hot?
Post by: stevec22 on August 11, 2020, 08:32:51 pm
My AquaHot sends heat to the dash defrost vents only. 
Title: Re: Dash aqua hot?
Post by: Caflashbob on August 11, 2020, 08:44:36 pm
So the dash heat is not engine antifreeze?  Interesting.  Fed from the coaches aqua hot?  I tried the zone one furnace and then turned on the dash fan.  Nothing.  Either I do not understand the system or some previous owner disconnected it. 

The diagram says 12 volt from the ignition switch or the aqua hot unit.

Safer motor wise to run the engine stuff separate and use the aqua hot internal heat exchanger loop for the heating loops and If by the mixing valve in the dash is open to allow hot aqua hot into the dash and the fan in the dash is on to put out heat wherever the area select switch is set. 

Floor, dash or defrost.

Is this the way it was built to be used?

Anyone test there older coach on aqua hot to see if this works....

To disconnect the unit versus just turn off the fan switch?

I suppose the test is to turn on the ignition with zone 1 outputting hot air and turn on the dash heat fan and open the valve to see what comes out?

The owners manual says nothing about the bay thermostat or any interface with the dash heat.

Interesting...
Title: Re: Dash aqua hot?
Post by: D.J. Osborn on August 11, 2020, 08:53:43 pm
I suspect your 1997 non-slide U320 is wired like our 1995 U320. The dash blower/heat/defrost is completely separate from our Aqua-Hot system. The Aqua-Hot supplies heat to a blower/set of coils under the couch (just behind the driver). There is no electrical or coolant interconnection between the dash system and the Aqua-hot system. My understanding is than in later years (with a slide) there is some electrical interconnection between the two systems.
Title: Re: Dash aqua hot?
Post by: Caflashbob on August 11, 2020, 09:00:13 pm
So David your dash heat is engine antifreeze supplied?  Like I mentioned the included in the owners manual wiring showing a aqua hot wiring connection got me to inquire.

The 98 owner says his defrost runs off aqua hot...

Anyone seen a engine antifreeze line to the dash?  Or a aquahot line to the dash?
Title: Re: Dash aqua hot?
Post by: craneman on August 11, 2020, 09:11:09 pm
My center dash register on top blows hot air along with the air at the bottom of the couch. When the ignition is on it stops blowing. Roger has posted a work around to stop air coming out there with the ignition off.
Title: Re: Dash aqua hot?
Post by: Caflashbob on August 11, 2020, 09:13:53 pm
So a 99 dash runs on aquahot.  I have seen posts where the poster disabled that function. 

Your 99 has a much larger btu dash heat and air than a 97 and 98 has.

Title: Re: Dash aqua hot?
Post by: D.J. Osborn on August 11, 2020, 09:16:56 pm
So David your dash heat is engine antifreeze supplied?

As far as I know the dash heat on our 1995 is supplied by a line from the engine using the same coolant that flows through the engine.
Title: Re: Dash aqua hot?
Post by: SteveB on August 11, 2020, 09:23:41 pm
So David your dash heat is engine antifreeze supplied?  Like I mentioned the included in the owners manual wiring showing a aqua hot wiring connection got me to inquire.

The 98 owner says his defrost runs off aqua hot...

Anyone seen a engine antifreeze line to the dash?  Or a aquahot line to the dash?
So Bob, I've had the sad misfortune to see both green boiler fluid and red coolant dripping from the front of my coach. A very hard way to prove a point.

Steve
Title: Re: Dash aqua hot?
Post by: Pamela & Mike on August 11, 2020, 09:33:51 pm
On a '97 320 with an A/H system there is 2 heating coils in the dash. 1 is run off the engine just like any car, truck or RV.  There is another that is heated through the A/H. In other words 2 separate systems in the dash.

Mike
Title: Re: Dash aqua hot?
Post by: craneman on August 11, 2020, 10:01:10 pm
The registers never get hot when I am driving maybe need to reverse engineer Rogers system to get Aqua Hot heat to the defroster when the ignition is on.
Title: Re: Dash aqua hot?
Post by: Caflashbob on August 11, 2020, 10:14:25 pm
Mike you mean the dash system?  Not under the couch? 
Title: Re: Dash aqua hot?
Post by: Roger & Susan in Home2 on August 11, 2020, 11:25:26 pm
If your AH is on (thermostat on) in the LR the AH heated coolant is pumped through the dash heat exchanger and one or two more heat exchangers in the LR/Kitchen.  Each of those other than the dash one has their own fans. If the ignition is on the dash blower does not operate under AH control if the thermostat is calling for heat.  If you turn on the coach heat then the dash blower runs and routes heat from the engine coolant heated heat box to wherever your dash heat controls are set. 

Maybe Rudy will tell us exactly what happens.
Title: Re: Dash aqua hot?
Post by: Caflashbob on August 12, 2020, 12:01:15 am
My 97 does not operate that way.  Not sure why. 
Title: Re: Dash aqua hot?
Post by: Pamela & Mike on August 12, 2020, 07:51:26 am

Yes
One fan motor for both heater coils that circulated air depending on which side of the system you are using. That is A/H side or engine side.

Mike
Title: Re: Dash aqua hot?
Post by: Pamela & Mike on August 12, 2020, 08:00:26 am
My 97 does not operate that way.  Not sure why. 

The interface relay is stuck/failed

Mike