Multiple Items, will be a long read... Alarm at 3;30AM, 2 Stage Fan Clutch, and other

[KenEhresman]

One more item, While running coach the coolant circulates from engine through aqua hot to heat water.. at faucet it appears to get hot.... the front and rear zones for the aqua hot heater though never really blow the heat like I would think they should.... it is pretty much just cold. When my webasto is firing right ( it is not again" it will heat it and work correctly, with plenty of heat coming from those small heat exchangers and the circulation pumps all work correct. wondering how these aqua hot heat exchangers are built? they don't seem to efficiently take the heat from the running coach which is 175 on the laser to the input side of the aqua hot and transfer it to the closed loop system of antifreeze in the fired heat exchanger and registers in the coach... anyone experience similar issues? dash heat will blast you out, but the rest of coach is forced to be running on ac rooftop heat strips to stay warm....

[BoaterAl]

Would it be possible to get some info on your coach ? Converter, year, model posted would help. Likely another owner might have experienced this issue.
Just trying to help,
Thanks,
AL

[KenEhresman]

Sure, I forgot that part... its and XL chassis, 1999 last of the rivets.... and a featherlite conversion... from what I have been told, this particular featherlite was build up in Oklahoma, and seems to be a bit of a one off coach...

thx

[Gil_J]

The alarm may be the engine bay fire alarm. If they get wet they give false alarms. The sensor is directly over the head of the engine.

Got to run, so I'll answer the other questions later, if no one else does.

[KenEhresman]

I had accidentally left the driver rear bay open that houses the aquahot... maybe there is a detector there that got wet? it did rain that day.... drizzle anyway... the coach had been sitting for 3 days idle.... got me thinking there is a sensor in that bay?

[Gil_J]

Your fan clutch is always supplied 12V. It is activated by supplying a negative return. You may be able to provide a direct return at the fan clutch connector. If so, turn the key on, but don't start the engine. If you hand spin the fan and apply the return jumper you should see the fan slow down.

If you have a known good relay, break the coil tabs off. Pull the low speed fan relay. Again, ignition on, engine off. Inserting the broken tabbed relay should result in the fan slowing down. If this works, the problem is the relay. If it doesn't the return feed is not making it to the clutch or the clutch is bad.

The low speed relay is worked hard, so its failure after 15 or so years isn't a surprise. At less than $5 a relay, just replace all 3 fan relays.

[KenEhresman]

12v and not 24? i'll guess these relays are in the back engine compartment connection box?