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KenEhresman
02-05-2017, 10:23 PM
No heat from aqua hot when running down the road. Not sure where to go with that. Do I need to turn on the block heater switch ( aqua hot 12v circulation motor that feeds engine) while running?

After 3'hours there was no heat. Dash heat worked fine but both aquahot zones no heat.

I also noticed there was no R31 relay in front panel. It's a 24v relay. Index says something about preheat??
Gil_J
02-05-2017, 10:46 PM
There should be enough engine water pump generated flow that you don't need to turn on the preheat. If you have flow control valves at the engine, make sure they are open.

Maybe a dumb question, are the furnace controls on for the zones you want heat to? The AH will fire its burner if it's not getting enough heat from the engine heat exchanger.

Disclaimer, all AH models may not work the same.
KenEhresman
02-06-2017, 09:35 PM
Yep. Furnace controls ok. Not sure where the circulation valves would be. Will look in engine compartment but I get hot water from faucet after driving
Gil_J
02-07-2017, 08:22 AM
Hmmm, if the furnace controls are working, what's not working? The engine heat exchanger only supplements the available heat in the AH. The AH burner may still come on, even with the engine running. I can't imagine an interlock that prevents the burner from firing just because the engine is running.
KenEhresman
02-15-2017, 09:45 PM
Upon inspection of the AH I clearly see the in/out path of the engine circulation. Appears to be the outside lines with the fuel and hot cold near middle.... There is a circulation pump on the input side of the AH that only comes on when I press the engine heat button in the kitchen panel behind door (2000 vantare). It would seem logical to me the engine coolant can't flow through a circulation pump if it is not running.... I'm going to run some thermal test tomorrow on high idles with laser to see when I get heat circulation....In and out of the AH

one more off topic AH question.... When shutting it down with the switch (not the thermostat control) it just shuts down without a purge cycle. Is that normal?