[Bob Standeford]

I have antifreeze leaking in front left side in front of driver. What's up there. the heater for winter? If I take the dash off can I do a temp. fix by just closing off the line after removing it from the core box? I've not opened it up yet. I just assumed I could get to it from the inside.

[encantotom]

hi bob,

i have gone through this same thing. there are only two things up there with antifreeze. one is the heater core that has heater hoses from the engine, the other is the aquahot. on mine, there is aquahot clear tubing that runs from side to side of the dash, but if it was leaking you would be able to tell it easier as it would be at your feet.

on mine, it was the heater core itself. if you take the top cover of the dash off, you can see the box with the heater core in it. it is black plastic. if you are lucky, it will be that the hoses are loose and you can try and tighten up the hose clamps. i was not so lucky. mine was the core itself.

i was also getting coolant seeping around the center console on the carpet after a while. and it used gallons of coolant.

to take the core out you have to remove the entire dash. i took the easy way out and capped off the hoses at the back valve manifold under the engine. if you are lucky, you can turn those valves off at the rear manifold, but i was not lucky there either as the packing leaked when closed. so i put a loop of hose at the valve and left them on.

my aquahot also has lines to the defroster, so that is all i ever would care about so i dont go where it is cold enough to need the dash heater. plus my aquahot has whisper heaters at the drivers and passenger ankles.

tom

[RussWhite]

Bob,

Just so you know, both systems that Tom has described may be valved off at the rear of the coach. On my coach, the valves are clearly labeled. Look just to the left of the engine block and above the oil pan.

There have bee many reports of these valves leaking if they are used. That's not much help is it? I guess I have just been lucky and mine don't leak with usage. I valve off the heater core in the summer. YMMV
Russ

[Bob Standeford]

Ok if it comes from the back block how do I find out which handle to turn off, I think I have 4 on that block. I didn't think about the AH going up there, can you hear the fan. if it's on?

[encantotom]

there is a plastic label back there on the frame rail on mine

and mine DID leak a lot when the valves were closed.

tom

[RussWhite]

Let me try to confuse you all.

There are two separate coolant ( anti-freeze ) circuits in our Aqua-Hots. One is engine coolant, the other the fluid in the AH boiler. They never mix if all is well.

The coolant in the boiler is circulated to different location in the coach depending upon the setting of thermostats.
The other circuit is contained in a heat exchanger inside the boiler. The engine coolant is circulated by the engine water pump when the engine is running, or by a a AH pump for engine preheat if it's cold and you turn it on.

So when you turn the valves off for say AH at the back of the coach you are stopping flow in engine loop only. You will not heat your boiler when driving and you will not be able to preheat the engine when desired.

If you turn the valves off for the heater, you are stopping flow to the heater core that is the heart of the dash air management system.
You may also have a AH radiator and fan up there or as in my case, the air from the AH radiator in the curb side bay may be ducted to outlets near the driver's and passengers feet. Got it? Russ

[Trainer]

Bob, I have sent you an email with my phone. Please call for more info on AH fan coil operation.

[encantotom]

i really dont think it is his aquahot pex lines. or he would have coolant on the floor.

and the guys are right. one set of valves stops coolant flow to the dash heater. the other set of valves is coolant flow to the aquahot.

tom