Aqua Hot FYI

[tikitom]

For all those with aqua hot systems. When doing your routine maintenance, check the condition of your radiator cap. Ours was dry rotted and caused our antifreeze to evaporate leaving us with no hot water or heat. Luckily we discovered this before any damage to the system. Just sharing.

[Stretch]

I w
L check mine. Have noticed mysterious loss of coolant. Have had plastic valve replaced already. That was to have stopped my coolant loss.


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[zmotorsports]

I replace mine about every other service just to be on the safe side. I also carry a spare in my toolbox.

Good idea mentioning it though, that is something many may not check or even think to check.

Mike.

[Stretch]

Wait a minute, doesn't the radiator vent into the coolant recovery tank?


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[zmotorsports]

Originally Posted by Stretch

Wait a minute, doesn't the radiator vent into the coolant recovery tank?


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If you are talking about the surge tank for the Aqua-Hot then yes, if you are talking coolant tank for engine then NO. Two separate systems.

The pressure cap for the Aqua-Hot is right on top of the boiler unit itself and is connected to the surge tank for the Aqua-Hot, usually mounted remotely in many coaches. If the pressure cap is defective it will not hold the proper pressure so the glycol mixture will expel the boiler tank prematurely plus could also prevent it from drawing the glycol back into the boiler as it cools trapping air in the boiler tank.

I have had the guts fall out of pressure cap, the rubber gasket get deformed and not seal so the OP makes a good point to check them periodically, however, for the $12-15 dollars each I just replace mine every other service and have not any issues thus far on my own unit.

Mike.

[tikitom]

Mike, you are exactly right. When the radiator cap went bad we lost our vacuum. The overflow tank was full regardless if the system was on or not. Being unfamiliar with the system we didn't pay much attention to it. That is until I got in the shower and had no hot water. The heater stopped working as well. Good thing it was our last day out. Came home and started trouble shooting. Everything looked good to me. I did notice a faint smell of antifreeze when I was in the bin. Decided to call the folks at aqua hot for help. When they ask how much fluid was in the overflow tank, I told them it was showing full even though the system was off. First thing he said was look at your radiator cap. Sure enough the seal was dry rotted. He explained how we had lost the vacuum and the antifreeze had evaporated. That explained the smell. Topped off the system with new antifreeze and replaced the cap. Have had heat and hot water ever since.

Tom
2001 Dynasty

[Jeff753]

Along the same lines inspect the blower motor rubber o ring and mounting rubber feet grommets. I had started blowing a little black smoke and it was due to brittle o ring and mounting feet grommets.


Jeff
2001 Dynasty Regent tag axle
Cummins 350 8.3 ISC

[tikitom]

Jeff, we have the exact same coach. Have had ours only a year. We love it. Is there any other issues you have run into?

[Jeff753]

Issues? Nothing major really. New charge air cooler, fuel lift pump, injector sleeve was leaking fuel on top...and turned this
into this

I would recommend changing the two capacitors in each ac until as well as the little 10 amp motor starter (photo below) located below the capacitors.
This little thing failed and shot fire out the side.
I also had my cooling unit on the fridge changed out by the Indiana Amish.
What motor and boost do you have?

[tikitom]

Jeff, tried to take this conversation to PM, but failed. Your message box is full.