Community Forums

TriCitySam · 06-08-2022, 11:05 AM

My '08 Allure has three heating fans - front, galley and rear. The rear one does not come on, the other two do.

I had a guy look at it, and even though it's heated with an Aqua Hot, he told me that from the Thermostat it goes to the heat pump on the roof and then to the fans. His take was that there was an issue with the circuit board in the heat pump and it wasn't sending juice to the fans.

Does that make sense? I understand it can be $1000 - 1500-1+ to replace the circuit board.

MrMark52 · 06-08-2022, 12:31 PM

I would track down the Owner and Service Repair manuals for your system and read them. They usually provide a glimmer of where to look and understanding of how the system is supposed to work and troubleshooting methodologies.

BonS · 06-08-2022, 07:03 PM

My 45' 2009 Allure with Aqua Hot has two Aqua Hot heating zones: front and rear. My front zone has 3 heat exchangers, with fans, at the front door, galley and mid way near the 1/2 bath. The rear zone has 2 heat exchangers with fans. One under the bed and one in the rear bath. Even though the thermostat runs my 3 rooftop heat pumps the wiring for the Aqua Hot heat demand runs directly to the Aqua Hot control board located adjacent to the Aqua Hot itself.

There is also a heat exchanger for the wet bay but no fan.

It sounds like you only have one fan in the rear? Then if that fan fails it does become a bit harder to determine the cause. You can look at the AH controller to see if the zone 2 LED is lit. That tells you that your AH is trying to turn on the fan. (My LED's are so dim that I remove the cover plate to see them better.) If the zone is trying to run and the fan is not running then I'd gain access to the fan to see if it's getting 12 volts. If it is then the fan is bad. Replacing the entire heat exchanger with fan is the easiest way to go in that case. Here's a replacement heat exchanger at a decent price.
https://hydronicheatingwarehouse.com...heat-exchanger

BrianGlenn · 06-09-2022, 08:06 AM

The AH heatilator fan control goes through a coupe of relays located in the AH bay. I would start there and measure voltage at the relay terminals. Let me know if you want me to post pictures. I am not at the Coach right now.

The tech is correct the thermostat controls heat pumps and AH fans but they are on separate circuits depending on “heat/cool” selection on thermostat.

Brian

Smitty77 · 06-09-2022, 09:08 AM

I always got a chuckle that Gas was heat and Electric is Heat Pump. The chuckle, was because with Aqua/Hydro Hot's, it's actually either Diesel or Electric (IF the Electric heating element is on

! With our Magna and the AH130 series Dual Electric Elements - we run our Diesel Burner more for regular exercise, then actual need for heating and or hot water... The Dual Element keep up with 95% + of our needs. So it's really easy to get the settings on the thermostats confused...

Good luck sorting things out... And I'll follow to see what the root cause is

!
Smitty

wfalch · 06-09-2022, 02:27 PM

The Butler did it.

turbine52 · 06-09-2022, 03:15 PM

As stated, the rear heat is zone 2. I sometimes move the setpoint 10 degrees warmer for the first startup. I know it doesn't make sense, but it works. I find sometimes I need the Aqua hot on. Good luck. I wish I needed heat right now.

nacimiento · 06-09-2022, 04:19 PM

I have the same coach as yours. My zone 2 will not operate the fan on electric heat only. My AH must be on. Suggest if you have not already done so, turn on AH diesel, then turn on heat to highest temp on zone 2 only. If that does not work, I would check the fan motor. And good luck with that. It is a bugger to get to.

birdhunter · 06-09-2022, 11:29 PM

The technician is correct I believe your thermostat calls for Aqua Hot heat via a board in your air conditioner heat pump. If that board is bad in that zone you could have a problem but there are a lot of other things that could be causing it as people have pointed out. I don't know what kind of a heat pump you have but for a Dometic Penguin, a board is about $200. I can change out a board in 20 minutes. So $1,500 to change out a board seems more than a bit high. You can change out the whole heat pump for about that! What make and model heat pump do you have!