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Topic: I found a heater in my tank bay - standard or optional item on 2003???? (Read 953 times) previous topic - next topic

I found a heater in my tank bay - standard or optional item on 2003????

In preparation for installing a Seelevel system on my new-to-us 2003 U-320, I found there is a heater in my holding tank bay.  There is a small radiator (about 12x6 inches) with two hoses (black in color, like engine coolant hoses) and a small fan.  It is near the fresh water tank on the passenger side of the coach.

Is this a standard or even optional item from Foretravel?  Does anyone else have one of these in their 2003?  Original owner is deceased, so cannot get info.  Guess I could call Triana, but he is hard to get hold of.  Thought it would be easier to ask here.

Jim
Jim McNeece
2003 U320 40'
2017 Chevy Colorado Tow

Re: I found a heater in my tank bay - standard or optional item on 2003????

Reply #1 –
Quote from: indio192 –
In preparation for installing a Seelevel system on my new-to-us 2003 U-320, I found there is a heater in my holding tank bay.  There is a small radiator (about 12x6 inches) with two hoses (black in color, like engine coolant hoses) and a small fan.  It is near the fresh water tank on the passenger side of the coach.

Is this a standard or even optional item from Foretravel?  Does anyone else have one of these in their 2003? 

We have the same - it's an Aquahot loop controlled by the knob thermostat on the face of the Manabloc cover.

Michelle
Learn every day, but especially from the experiences of others. It's cheaper!  - John C. Bogle

2000 U320 36' non-slide / WildEBeest Rescue
2003 U320

Re: I found a heater in my tank bay - standard or optional item on 2003????

Reply #2 –
Quote from: Michelle –
We have the same - it's an Aquahot loop controlled by the knob thermostat on the face of the Manabloc cover.

Michelle

Same one on ours.
The selected media item is not currently available.Barry BEAM #16014
2003 U320 40' AGDS
Beamalarm, Foretravel technical help and specifications
"Whatever the mind can conceive and believe, it can achieve"

Re: I found a heater in my tank bay - standard or optional item on 2003????

Reply #3 –
Jim, like Michelle's coach,  our 2001 U320 has the same heat exchanger in the tank bay.  Hot coolant is supplied by the AquaHot.  Our thermostat is located in the panel above the water pump just forward of the Manablock.  Of course it only works if your AquaHot is running on diesel or 110v.  When you are driving the engine coolant heats the AquaHot coolant and thus the tank bays are heated when it is cold and you are driving.

Keep on exploring and asking questions.  There are more answers here than anywhere else.
Roger Engdahl and Susan Green
2001 U320 3610 #5879 (Home2) - 2014 Jeep Cherokee or 2018 F150
Hastings, MN

Re: I found a heater in my tank bay - standard or optional item on 2003????

Reply #4 –
BTW - there's one on the driver's side, too, behind the white panel/back wall of the utility bay.  It's for the black and grey tanks. 

Here's a photo of what's behind "door number 2" (more photos here http://www.foreforums.com/index.php?action=media;sa=album;in=315 )

The selected media item is not currently available.

Quote from: Home2fromHastings –
When you are driving the engine coolant heats the AquaHot coolant and thus the tank bays are heated when it is cold and you are driving.

Yes, and if you're just overnighting somewhere in a temperate climate (aka not needing furnace heat), the residual heat from the engine loop will be enough for hot water and showers the next morning, no need to fire up the AquaHot itself).

-M
Learn every day, but especially from the experiences of others. It's cheaper!  - John C. Bogle

2000 U320 36' non-slide / WildEBeest Rescue
2003 U320

Re: I found a heater in my tank bay - standard or optional item on 2003????

Reply #5 –
Thanks guys.  I really appreciate you tearing your bays apart for me.

I have a feeling tomorrow will be an "enlightening" experience as I install the Seelevel.

Jim
Jim McNeece
2003 U320 40'
2017 Chevy Colorado Tow

Re: I found a heater in my tank bay - standard or optional item on 2003????

Reply #6 –
Quote from: indio192 –

I have a feeling tomorrow will be an "enlightening" experience as I install the Seelevel.

Jim

Be sure to take photos and post the resulting tutorial.  If/when our Javelina/Audit ever dies (or sensors become unavailable) we are likely to be installing a Seelevel ourselves and will appreciate the knowledge ^.^d
Learn every day, but especially from the experiences of others. It's cheaper!  - John C. Bogle

2000 U320 36' non-slide / WildEBeest Rescue
2003 U320

Re: I found a heater in my tank bay - standard or optional item on 2003????

Reply #7 –
Jim,

I recommend that you add some information about your coach as a signature line. It helps us to remember what Foretravel you enjoy. Look at some of the other signature blocks to see what people normally include.
J D Stevens
1997 U295 CAI 36' Build #5085
2002 Subaru Outback
Motorcade 16869
Bellville, TX

Re: I found a heater in my tank bay - standard or optional item on 2003????

Reply #8 –
Just FYI, I believe on my 2003 U-320, these water bay AquaHot heaters share the circ pump with the bathroom circuit so I believe the bathroom thermostat needs to be on for the basement heaters to work properly.
Bill & Deanne Brown
'03 U-320 Previous Owner in Houston

Re: I found a heater in my tank bay - standard or optional item on 2003????

Reply #9 –
Bill is correct that the basement heating loop shares the number two circulating pump with the bathroom heating loop.  Actually one heating loop that goes from the heater to the bathroom to the basement and back to the heater.

But, the basement thermostat controls the basement fan coil fan and number two pump independent of the bathroom thermostat that controls the bathroom fan coil fan and number two pump.

Hope this helps sort the workings out.
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: I found a heater in my tank bay - standard or optional item on 2003????

Reply #10 –
Quote from: Rudy –
Bill is correct that the basement heating loop shares the number two circulating pump with the bathroom heating loop.  Actually one heating loop that goes from the heater to the bathroom to the basement and back to the heater.

But, the basement thermostat controls the basement fan coil fan and number two pump independent of the bathroom thermostat that controls the bathroom fan coil fan and number two pump.

Hope this helps sort the workings out.

So there are in reality 4 seperate thermostats?  If the aqua hot unit is on the basement thermostat is the controller for its loop.  No off switch?  Be nice if it had an off switch.  On 115 volt the amount of btu's is limited and I find I reduce heat to some coach areas to have more in others. 

Are all the areas hot antifreeze always in the units and the thermostat controls the fan only?
"Riding and rejoicing"
Bob
1997 U320 40' Mid entry, build 5132,  wtbi ce27, 4th owner
2007 Solara convertible
2 prodeco tech outlaw ss electric bikes

1095 watts solar
08 Ls 460 and a sc430
2000 Ford F-250 superduty 4x4

Re: I found a heater in my tank bay - standard or optional item on 2003????

Reply #11 –
Agree with Rudy...
A simple way to check this is to shut off all interior thermostats, then pinch the bulb sensor between two ice cubes. In our case that sensor is in the water manifold bay passenger side. Both heat exchanger fans in the basement should turn ON.
Dick, '03 U320 40' Tag, 2 slides, Coach #6075
Full Timers
2009 Honda CR-V

Re: I found a heater in my tank bay - standard or optional item on 2003????

Reply #12 –
Quote from: Caflashbob –
If the aqua hot unit is on the basement thermostat is the controller for its loop.  No off switch?  Be nice if it had an off switch. 

Turn Basement Thermostat higher
The selected media item is not currently available.Barry BEAM #16014
2003 U320 40' AGDS
Beamalarm, Foretravel technical help and specifications
"Whatever the mind can conceive and believe, it can achieve"

Re: I found a heater in my tank bay - standard or optional item on 2003????

Reply #13 –
Bob

Basement thermostat keeps basement as low as 40 degress to 50 degrees.  So as long as ambient is above 40 degrees, the basment will not call for heat.

To turn basement thermostat off, pull one wire loose from thermostat and/or put a switch in that wire.  Defeating basement heat in freezing weather not recommended.
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: I found a heater in my tank bay - standard or optional item on 2003????

Reply #14 –
Quote from: Rudy –
Bob

Basement thermostat keeps basement as low as 40 degress to 50 degrees.  So as long as ambient is above 40 degrees, the basment will not call for heat.

To turn basement thermostat off, pull one wire loose from thermostat and/or put a switch in that wire.  Defeating basement heat in freezing weather not recommended.

Yes been there, done that.  -30F in an ored with normal exposed tanks and batteries.

No amps at -30F.  Dry camped at Taos, New Mexico. 

Does the antifreeze circulate through all the radiators all the time?  Do the basement units have fans? 
"Riding and rejoicing"
Bob
1997 U320 40' Mid entry, build 5132,  wtbi ce27, 4th owner
2007 Solara convertible
2 prodeco tech outlaw ss electric bikes

1095 watts solar
08 Ls 460 and a sc430
2000 Ford F-250 superduty 4x4

Re: I found a heater in my tank bay - standard or optional item on 2003????

Reply #15 –
Bob,

The coolant only circulates when the zone thermostat calls for heat and then only thru the fan coil(s) in the loop(s) calling for heat.

Foretravel installed fan coils so fans are in the basement.
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: I found a heater in my tank bay - standard or optional item on 2003????

Reply #16 –
Quote from: Rudy –
Bob,

The coolant only circulates when the zone thermostat calls for heat and then only thru the fan coil(s) in the loop(s) calling for heat.

Foretravel installed fan coils so fans are in the basement.

So there are solenoids off a loop circuit?  Or all the way to the aqua hot unit?

Exactly how does the system work?
"Riding and rejoicing"
Bob
1997 U320 40' Mid entry, build 5132,  wtbi ce27, 4th owner
2007 Solara convertible
2 prodeco tech outlaw ss electric bikes

1095 watts solar
08 Ls 460 and a sc430
2000 Ford F-250 superduty 4x4

Re: I found a heater in my tank bay - standard or optional item on 2003????

Reply #17 –
Bob,

I see your coach is a 1997 so you have the Model 431/12 heater.

When the bathroom thermostat calls for heat, it grounds a electrical loop going from the thermostat down to the heater.  This ground latches the number two relay which sends 12vdc to the number two pump and to the fan in the bathroom fan coil.

The number two pump circulates hot coolant to the bathroom fan coil and the basement fan coil.  Only the bathroom fan coil fan runs so only warm air circulates in the bathroom.  This applies to the living room thermostat, number one pump and heating loop one fan coils which there are usually three.  This applies to the bedroom thermostat, number three pump and the heating loop three fan coil which there is usually one.

When the basement thermostat calls for heat, it sends a 12vdc signal directly to the number two pump and to the fan in the basement fan coil.  The number two pump circulates hot coolant to the bathroom fan coil and to the basement fan coil.  Only the fan in the basement fan coil is running so warm air in basement and a warm fan coil in the bathroom cabinet but no warm air in the bathroom.

For the folks with coaches starting in 2003 that have an electronic control board, the thermostat sends a signal to the control board which, seeing which thermostat is calling for heat, starts the corresponding pump and fan(s) in the proper fan coil(s) as described above.

Bob, here is a link to the wiring diagram in Appendix A on page 76 of the shop manual for your heater.  Hopes all this helps.

http://www.aquahot.com/eSource/ecom/eSource/staticpages/documents/AHE-100-02S%20Service%20Manual%20Rev.%20B%209-27-2011.pdf
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: I found a heater in my tank bay - standard or optional item on 2003????

Reply #18 –
Thanks Rudy.  Now I start to understand.  Seems like an expensive piece of equipment.  No wonder other motorhome builders have built their own versions. 

Bob
"Riding and rejoicing"
Bob
1997 U320 40' Mid entry, build 5132,  wtbi ce27, 4th owner
2007 Solara convertible
2 prodeco tech outlaw ss electric bikes

1095 watts solar
08 Ls 460 and a sc430
2000 Ford F-250 superduty 4x4