HH zone one issues

[Brett63]

Got a quick question. For some reason when our HH is on we are now not getting any hot air out of any dash vents. I can hear the fan running, I checked the octopus box and all hoses are connected, but we get nothing blowing out. We get full force air when the dash AC or heat is on, but we don't get much heat at all on dash heat.

Any ideas on where my issue resides, or what it may be?

2009 Signature

[Ivan K]

Is the dash HH not blowing with ignition on or off? Different situations and solutions. Ours quits blowing AH dash heat when ignition ON and switches to engine heater. Apparently by design and I still haven't figured out how to make it to use dash AH heat at will, while driving. The way they plumbed and wired the dash control and vacuum through a set of relays and solenoid valves is mind blowing to me and my charts don't make it clear.

[Frank McElroy]

Have you checked to see if the water valve on the hot water hose from the engine to the heater is fully opening?  Both hoses connected to the heater should be near the engine temperature with the hose leaving the heater a bit cooler.

[Brett63]

34 minutes ago, Ivan K said:

Is the dash HH not blowing with ignition on or off? Different situations and solutions. Ours quits blowing AH dash heat when ignition ON and switches to engine heater. Apparently by design and I still haven't figured out how to make it to use dash AH heat at will, while driving. The way they plumbed and wired the dash control and vacuum through a set of relays and solenoid valves is mind blowing to me and my charts don't make it clear.

When engine and ignition is off

 

29 minutes ago, Frank McElroy said:

Have you checked to see if the water valve on the hot water hose from the engine to the heater is fully opening?  Both hoses connected to the heater should be near the engine temperature with the hose leaving the heater a bit cooler.

it worked all of Oct/Nov and Dec. then we made it to FL and didn't need heat until a couple nights ago. Now no air at all coming out of heat vents when HH is on. I can hear the fan running in the dash, but no air exiting. I have to assume the octopus box with all the heater hoses is also where the HH fan resides. I can't see any water lines going to it, but it is very crowded in there. 

[bobdinsmore]

I don't have AquaHeat but it sounds like a vacuum motor for the dash vent is not opening.

[Ivan K]

Just now, bobdinsmore said:

I don't have AquaHeat but it sounds like a vacuum motor for the dash vent is not opening.

The thing is that with ignition off, there is no vacuum to operate the duct doors and they should default to center position. Wonder if all the positions work with IGN ON (with vacuum motor pump) or with engine running (with air operated generator).

[Brett63]

Ivan K, they appear to. If I switch to mid body that is where air blows from, def, same and feet same.

Now I know that I can see what says to be an A/C control module in the dash that has a couple 8/10 pin connectors one a board of some kind (hard to see) and and actual module about 4" square.

I am wondering if this has a control over door positioning? I simply have no idea. I am going to look tomorrow and pull info from that module and see if I can find any online info on it.

[Ivan K]

Good plan, yours is probably different because I only have a small circuit board attached to temp control selector for the water valve actuator outside firewall. Everything else is just wires to a large complex control board behind the side cover.

[Guest Ray Davis]

Is the op referring to his dash HVAC that is engine driven or HH which must stand for Hydro-Hot, essentially an Aqua-Hot.

Are they connected in some way?  On my 03 Windsor they are completely separate systems.

Ivan,  I can run my Aqua-Hot while driving and it's great and I don't need to use the AQ burner just engine heat.  Plenty of hot water when driving too we could shower while driving.   😲

[Ivan K]

10 minutes ago, Ray Davis said:

Ivan,  I can run my Aqua-Hot while driving and it's great and I don't need to use the AQ burner just engine heat.  Plenty of hot water when driving too we could shower while driving.   😲

Ray, our dash AH heat only works with engine off. As soon as I turn ignition ON, the front would switch to regular engine heating controls up front and the fan stops. All the other registers behind me continue working. There is some funky circuit that does that and I haven't figured it out yet. The regular dash heat works fine once up to temp but it still bugs me not knowing how it is done and why.

[Guest Ray Davis]

26 minutes ago, Ivan K said:

Ray, our dash AH heat only works with engine off. As soon as I turn ignition ON, the front would switch to regular engine heating controls up front and the fan stops. All the other registers behind me continue working. There is some funky circuit that does that and I haven't figured it out yet. The regular dash heat works fine once up to temp but it still bugs me not knowing how it is done and why.

I guess Manaco thought that was a nifty feature.  When we drive in really cold temps we can't have too much heat, I've used both heaters up front and it heats us very nicely.  Not only that, the whole coach can be warm if I want

If I was guessing, I think there is an ignition feed to the AQ unit where a relay cuts off the power to the pump and fan for zone 1.   Since it probably stops the pump as well as the fan the relay would more than like be near the pump.   However if the pump is not stopping the relay could be up front near the fan.  If the pump continues to run,  then a switch could supply power to the fan when you want heat up front.

[Brett63]

Yes when I drive the zone 1 appears to be shut off, at least to the dash vents. I have not had my wife check the vents under the kitchen counter. All other vents operate as normal while driving with HH on. I am thinking this AC module may have something to do with it. I will do some more investigating in the am.

[vito.a]

Brett, I assume by HH you mean the Aqua-Hot heating system? 

Are you running it on diesel, or pure electric? Also, do you have the front thermostat zone mode set to Furnace?

I have not seen doors or covers on the Aqua-Hot vents that require vacuum.  They should blow hot air regardless of the settings on engine/dash heating system.  

I would check the blower fan and also the recirculation pump for that zone.  Many times they will stick.  You can usually tap on the recirculation pump and get it to start pumping.  You will need to remove the stainless cover over the Aqua-Hot burner assembly to access the pumps.  While you are in there check for 12v power to the pump also.  

[Ivan K]

1 hour ago, Ray Davis said:

I guess Manaco thought that was a nifty feature.  When we drive in really cold temps we can't have too much heat, I've used both heaters up front and it heats us very nicely.  Not only that, the whole coach can be warm if I want

If I was guessing, I think there is an ignition feed to the AQ unit where a relay cuts off the power to the pump and fan for zone 1.   Since it probably stops the pump as well as the fan the relay would more than like be near the pump.   However if the pump is not stopping the relay could be up front near the fan.  If the pump continues to run,  then a switch could supply power to the fan when you want heat up front.

Well, here is my circuit diagram. I have no doubt one of the relays plays a role in this finicky configuration. The fan is the same dash fan, pretty sure as it blows very nicely. I gave up on this long time ago but this post made me curious again.

[Guest Ray Davis]

11 hours ago, Ivan K said:

The fan is the same dash fan

You don't have a fan for the dash HVAC and a separate fan for the AquaHot?

[Ivan K]

1 hour ago, Ray Davis said:

You don't have a fan for the dash HVAC and a separate fan for the AquaHot?

It does not appear so from the diagram. I never had the HVAC box open to see how the register is positioned in there. I might have time to check the function at Tawakoni this weekend, been a while.

[Guest Ray Davis]

The only AH I've ever been around is mine so I guess I thought they were all similar.    It's too complicated for me this morning.

What's happening at Tawakoni this weekend?   For those that are not from Tx, Tawakoni is a lake in North East Tx

[Ivan K]

34 minutes ago, Ray Davis said:

What's happening at Tawakoni this weekend?   For those that are not from Tx, Tawakoni is a lake in North East Tx

Just a shake down trip before going South and West next month... helps us remember things that I would otherwise forget to load with us. Wish the forecast was better but it will test the AH for sure.

[Guest Ray Davis]

1 hour ago, Ivan K said:

Just a shake down trip before going South and West next month... helps us remember things that I would otherwise forget to load with us. Wish the forecast was better but it will test the AH for sure.

Sounds like a plan, have fun, it's supposed to be cold.   Well, cold by my standards, I think it's supposed to be in the 40s.  I don't do cold very well anymore, don't do hot all that well either.  I must be getting soft.    When it's cold I want it to be hot then right the opposite.  Seems like it's never just right anymore, it must be this daylight savings they keep doing.  Like the farmer said, they keep messing with the time their gonna ruin the crops. I say leave it alone

[Guest Ray Davis]

10 hours ago, Ivan K said:

Just a shake down trip before going South and West next month... helps us remember things that I would otherwise forget to load with us. Wish the forecast was better but it will test the AH for sure.

Ivan,  I don't know if you are on IRV2 but since you are heading west you may be interested in the Quartzite Momaco gathering.  Here is a link to the thread.

https://www.irv2.com/forums/f115/quartzsite-monaco-2021-gathering-518755.html

[Ivan K]

Thanks Ray, I read about it but we won't be in Q until sometime in March, we traditionally spend a week or two at a park by Big Bend SP with our snowbird friends from up North before flying through the cold of New Mexico to AZ.

[Guest Ray Davis]

9 hours ago, Ivan K said:

we won't be in Q until sometime in March

I suspect they will still be there,  it's not a 1 wk thing as one might imagine.  Some are there for quite a while and others move on.

I haven't been but from what I've gathered it's more of a campfire gathering, maybe do some projects on their coaches.

Even if you only drove out where they meet in your toad you could see if it appeals to you, wouldn't even have to stop

[Ivan K]

So, yesterday I had a chance to test the front AH dash function while driving and I think I have good understanding now. Drove in 30 degree weather and got her under the roof just before snow started.

When ignition is turned ON, dash fan control is returned from AH to the dash dial. That now makes sense to me. If the AH register is already hot, I get hot air, while stationary, and can adjust the blower speed at will. 

Brett, if you have only little or no dash heat while driving in cold weather, I feel that it is because the fresh air duct door above generator is normally open and letting cold air in, through the register. The door only closes with AC selector on MAX Air. Mine gets hot when I initially turn AC control to Max which closes the fresh air door, until the AC starts working against it. 

Once it warms up here, I will figure out a way to keep the firewall fresh air duct closed, I foresee few options or maybe even permanently. This effects the AH dash air as well as the engine coolant based heater that can't keep up with the incoming cold air.

[bobdinsmore]

Ivan,

 

I taped my dash door permanently shut with aluminum muffler tape and am 100% pleased with this solution. In both the hottest of summer and the coldest of winter. I have found I want only max heat in the winter and only max cooling in the summer. The only function I am missing is fresh air which I never used and still see no need. I still can control heat level and the fan speed with the dash control.

I also taped misc leaks in the under-dash area such as around the sliding step cover, around wire openings thru the firewall, etc.

[Ivan K]

Thanks for the reply, Bob. I may end up doing the same and not miss the fresh air intake the few days in between seasons here. It's not like sitting in a small car cabin. I already sealed the potential outside air leaks between the front cap and firewall too. Thanks.