Aqua Hot in bathroom not working.

[Ed Forbes]

Hi David,

Thanks for all the help so far. As soon as the weather will allow me a few hrs. outside, I will check out the electrics on the AH.

Will let you all know what I find.

Thanks Ed

[Roger Berke]

Most of the time when one heat zone is not working the check valve for that zone is stuck shut. Turn on the zone that is not working so that circulation pump starts. Rap on the check valve with screwdriver handle or medium size wrench. Also make sure that the three relays are pushed in tight into their sockets.

If the coolant is circulating you should feel the hoses above the check valves get warm and can verify that by checking the coolant return line (the hose behind the pump / check valve).

- Roger Berke -
Moderator - http://autos.groups.yahoo.com/group/HydronicRVHeating/

[Ed Forbes]

Hi Roger,

Both registers and their fluid hoses in the bathroom and hallway are hot, but the fans aren't running. I also checked with a volt meter and I'm not getting power at the fans. The tstat is in the on position and I hear a clicking sound when I ajust it up.

Appreciate you help.
Ed

[Rob Robinson]

Roger could you direct me to any info you have on how to remove and clean one of these check valves. I'd be particularly interested in what you have to do to prevent coolant loss.

[Roger Berke]

Rob

The check valves only stick on occasion. If you turn the heat on in your coach about every 30 days, then they probably will not stick again.

If you are having continued problems with a check valve, then you should replace it. Standard plumbing part that should be available anywhere for around $10.00. Check valve 1/2 X 1/2 (F)NPT Brass.

You will get minimal coolant loss when you remove the check valve (around 1/2 cup) only what is in the coolant line above. If your coach has compression coolant connections above the check valve, they can be difficult to reuse (they leak!).

- Roger Berke -

[Roger Berke]

Ed

This is the 'standard' wiring for your Aqua-Hot. Yours may be different. Check the middle relay inside the Aqua-Hot. On the left side, there will be two or three wires under one of the terminals. This is the positive power supply to the interior fan in the middle zone. The negative wire is one of the wires on the ground terminal post to the left of the fuse block.

- Roger Berke -

[Hisham Amaral]

Roger
Do you know the current carrying capacity of the panel mounted switch for the Aqua Hot? I would like to buy one and keep as a spare just in case.
Ed
I think you may have a sticky zone relay that turns on/off the heater fan, if the water is coming into the heater core but no fan. I would switch a known working relay into that zone and check to see if the fan will come on. If that does the job then I look up that relay from RS electronic or maybe Granger's they usually carry that type of relays.

[Doubledoc]

IN our '99 LX and our '06 M450LXI the thermostat in the toilet area is an interruption to ground for the bathroom fan. If it is not on then no fan in the bathroom area. The thermostat cover comes off easily. Check to be sure the wire connections are intact. The wire to the thermo spring control can come loose.

[Ed Forbes]

Just so I get a better understanding of what the relays do, or what they control,
1) Am I correct to assume that each of the relays controls both the power to the pump and power to the fans for there zones?
2) A potentially bad relay can still supply power to;
a) The pump and not the fans, and vise-versa
b) No power at all to either pump or fans

I had to leave the coach to get back for work, but I will get back to this problem over the weekend.

Thanks for all the help thus far and I will post the out come once I have corrected the problem.

Thanks Ed

[Roger Berke]

Originally Posted by Hisham Amaral

Roger
Do you know the current carrying capacity of the panel mounted switch for the Aqua Hot? I would like to buy one and keep as a spare just in case.

I have never measured the current, however I would expect it to be less than 2 amps. It is only the control box on this circuit. The motor has its own wire and fuse.

- Roger -