Aqua hot

[Richard Muha]

Just bought 2008 Marquis.  Furnace, Aqua hot works front of coach but not back.  Only blows cool air on back.  Thermostat set same temp for both locations on the furnace setting.  Does same for heat pumps?

Any thoughts 💭

[Steve Huber Co-Admin]

Rich,
Check your zone pumps inside the Aquahot as is sounds like you are not getting hot fluid to the bedroom exchangers. Also gently tap on the "check valves" normally just above the zone (circulation) pumps.
If neither the heat pumps or AQ are working heat. you probably have a thermostat problem.
Steve

[Richard Muha]

I don’t really know where the zone pumps are on the Aqua hot.  As far as thermostat goes, it seems to work fine for the A/C units.

[David T. Richelderfer]

As Steve indicated... "inside the Aquahot."  Take the outside door off by removing a couple of small screws and the several (3?) pumps will be there on the left side.

I do not know which Aquahot model you have, but this one is the one we have in our coach.  You can download the manual for your Aquahot from aquahot.com.

http://www.aquahot.com/files/service_manual/AHE-100-02S%20Service%20Manual%20Rev.%20B%209-27-2011.pdf

[Richard Muha]

Thx.  I believe I have the 600 D. I’ll check it out.

[Steve Huber Co-Admin]

Rich,
In the Coach Assist tech library (Private Members Only board) there is a link to all Aqua Hot manuals.
Steve

[Richard Muha]

Thank you.  I’ll check them out.  I must confess though, not very mechanically handy!

[Keith Moffett]

Richard
Plan to attend a Beaver rally.  There are plenty of folks there to do a walk through on these items. 
When one lacks a background in repairs perhaps an Aqua Hot is a tough first start.  To sit with someone and see what they are talking about as they explain it can make the understanding easier.
Remember, we all started as newbies.
BtW....there should be a label on the outside of the Aqua Hot box in the top right corner with the model and serial numbers. 

[Richard Muha]

Thank you and I do plan on going to a event soon, if possible.

[Lee Welbanks]

Just bought 2008 Marquis.  Furnace, Aqua hot works front of coach but not back.  Only blows cool air on back.  Thermostat set same temp for both locations on the furnace setting.  Does same for heat pumps?

Any thoughts 💭

Richard, In your post you state that the heat pumps do not heat in the rear zones. Sounds like a thermostat problem. I assume that your coach has three roof A/C Heat pumps, which are separate from the Aqua Hot system..Might want to check out the thermostat before digging into the Aqua Hot.

[Joel Ashley]

If you’re saying the rear heat pump isn’t working either, Richard, then the issue is more likely with the thermostat.  But be aware the AC heat pump won’t work when outside temps get below about 43F;  there’s not enough outside heat then to exchange (reverse AC) for.  If the AC works fine, then yes, tapping the rear hydronics supply pump valve can dislodge it if it’s stuck and resolve the issue.

Joel

[Richard Muha]

Thanks to everyone that replied.  My Marquis is a 41’ with only two 15,000 btu A/C heat pumps.  Both do not come on at over 45 degree outside temps.  I find it strange that the A/C works with both units using the same thermostat?
One other weird thing on the thermostat is that it has a zone 4 but no zone 3.  Also zone 4 seems to do nothing except when I put it in furnace mode, the Aqua hot blower switch in bathroom (switch on), the floor vent fan in bath comes on and blows cold.  If that zone is in any other setting the same switch does not light up or activate the fan.

I have a couple of other issues which I’ll post later.  For those I have an appointment in Tucson November 6 at Empire CAT.

[Lee Welbanks]

Richard, Do you know if the two A/C Heat pumps are original or have been replaced. Sounds like somebody has got the units wired wrong or the dip switches in the units not set correctly. I have never replaced one but I understand that you have to get the exact replacement model for the ones you hav
Would be great if somebody had a wiring diagram and the dip switch positions for these coaches.

[Joel Ashley]

In the Coach Assist section there are often helpful documents like this may prove to be, along with other troubleshooting and service manuals:   http://bryantrv.com/docs2/docs/ccc5.pdf

From what I’ve read, not personal experience, I don’t believe the 5-button Duo-Therm (now Dometic) has dip switches for the heat pump, although newer models do, and there are dip switches for the other functions of the thermostat;  just not the heat pump.  The heat pumps communicate with the thermostats via a red connector at the red P3 plug in the control box.  That’s for the outside ambient temperature sensor.  If that connector is corroded, disconnected, or plugged to the wrong place on the board, I’m not sure the pump would even show up on the thermostat.

But I’m probably off course here because apparently the heat pumps do register on his tstats.  Just sayin’ I don’t think there are dip switches for that specific function.  But his issue with a thermostat controlling both units may be dip switch related.

Our coach lists a third zone on both thermostats even though there’s only two used, one each tstat.  A third hydronics zone to me would be the bay.

Joel

[Richard Muha]

I turned on the heat pump for the rear last night in the master bed area.  What came on was the floor vents with just cold air.  I’ve had another RV with a/c heat pumps and they blow out the ceiling like the a/c.  Something is way off here and certainly above my pay grade.  I’m not that handy, + no way going on roof with two replaced hips.
Aqua hot seems to work up front and for now creates enough heat in the Coach, but the mornings here in Willcox Arizona are getting down to mid to high 30s.  🥶