Question number one. It seems that the automotive dash heater is not producing much hot air flow. With the heat and blower on high there is lots of fan noise but there is very litle warm air coming from the vents. Oddly there is a fairly good breeze from the defroster vents.
The system looks identical to the one in our old 1990 Dodge van.
What should I start to take apart to see what's blocking air flow?

Question number 2. The motoraid heater seems to only pump heat to the rear bedroom and adjacent hallway. Should there also be heat in the forward area? There are 3 vents and a plenum under the couch. When the propane furnace is on only one of these vents produces heat. Whats with the other 2? They are all coming from the same plenum.
Thanks in advance for the help.
Don

"When the propane furnace is on only one of these vents produces heat. Whats with the other 2? They are all coming from the same plenum."

A) The non-functioning vents are blocked.
B) All the air is escaping through the (PROBABLY SHORTEST RUN) functioning vent; the cure for this is to partially block (damp) this one. Most Barths don't have dampers in the vent pipes, but yours may - look and see if they have a butterfly-valve damper in them where they exit the plenum.
C) Remove the plastic diffuser and be sure it isn't blocked by, e.g., loose pieces of tape.

When we purchased our Barth the flexable duct work in the front was all loose do to no clamps on any connections. The ducts to the propane heater are all insulated type. All who wader are not lost.

quote:

Originally posted by Don in Niagara:
Question number one. It seems that the automotive dash heater is not producing much hot air flow. With the heat and blower on high there is lots of fan noise but there is very litle warm air coming from the vents. Oddly there is a fairly good breeze from the defroster vents.
The system looks identical to the one in our old 1990 Dodge van.
What should I start to take apart to see what's blocking air flow?

Most likely it is a Chrysler HVAC. I think the issue is a vacuum leak not allowing the diverters to work properly (there are four diaphragms...)

quote:

Question number 2. The motoraid heater seems to only pump heat to the rear bedroom and adjacent hallway. Should there also be heat in the forward area? There are 3 vents and a plenum under the couch. When the propane furnace is on only one of these vents produces heat. Whats with the other 2? They are all coming from the same plenum.
Thanks in advance for the help.
Don

There is, as others have posted, either a leak or a blockage to the front vents.

Thanks for the help folks.
Regarding the dash heat. I'm about to pull apart the dash area. I'll check that the heater vent hoses are hooked up ok. Are there vaccuum lines to look for? How do I find the "4 diagphrams", in the lines or at the fan motor, or somewhere else? I don't know what to look for.
Regarding the Motoraid heat. I just realized I'm not hearing any fan noise from under the couch. The "Aux Heat" hi-lo swich causes a fan to run in the heating unit under the floor of the closet in back but nothing from the front area!
Since we've only had the coach since May all the heating stuff is new to me. Don't even really know how all this is supposed to work in the first place. I've got literature on the propane heat but Barth hasn't provided a clue about the Motoraid.
What fun!
Don

My Breakaway has an electric vacuum pump, so I can just run that to check the system.

All the diaphragms are located at the air handler inside the right dash. The diaphragm/actuator for the inside/outside air is outside on the front of the air handler on mine. I found the hard plastic line totally deteriorated, so replaced it with rubber.

The remaining three could be checked by pulling the cover off the vertical section of the dash. My coach is front-entry, and the grab handle is on that cover. There's not much room to work.

I'm gonna guess that the MotorAid heat uses one fan, and the lack of heat to the front is related to the same issue with the propane furnace, in that the fan isn't distributing to that section.

The coach has 2 propane furnaces, front and rear. The front is under the couch and produces lots of heat from only one of the vents, when called for. I could guess one of these vents is a cold air return as in a household furnace? Maybe? Like I said they all run from the plenum attached to this furnace. Just funny that the other 2 are right beside the one that produces heat. They are all on the ends of the lower front of the couch with the access door between them.
The motoraid heater vents are different, round plastic vents in the bedroom, hall/bath area and one next to the storage drawer beneath the fridge. There are none further forward to heat the living/driving area to augment the dash heater. Also the one 'neath the fridge doesn't produce heat. The others are in pairs in the hallway and bedroom. Wonder why? In each case only one of the pair produces heat when the "Aux Heat" switch is on.
Love our Barth!
Don

Propane furnaces require a certain total minimum outlet area; it's possible one of the registers is a return, but I'd guess that there are at least two, and maybe a third, supply fed by that furnace.

I'm absolutely no help on the MotorAid thingie.

This may seem obvious, but there is a hot water shut off that is operated by the slide swithch that goes from cold to hot. Make sure this is operating properly as mine wasn't.

Here is what you might be looking at when the dash is apart. It is not as bad as it looks, One of the damper motors can be seen here,I believe it directs air between dash vents and heat vents, the damper that is hidden directs air between heat vents and defrost. The third damper selects outside air or recirculation.




Select the smaller image for a better view...

Ours was seized. It is over 6' long and the Dodge dealer could only come up with one barely 4'. I by passed it by opening it fully and installing 2 shut off valves on the heater hoses. Now I have either full heat, a little, or none depending on how much I open the valves.
The problem I have with the dash heat seems to be lots of fan noise but not much air thru the vents.
Don

quote:

Originally posted by Gary Carter:
This may seem obvious, but there is a hot water shut off that is operated by the slide swithch that goes from cold to hot. Make sure this is operating properly as mine wasn't.

Six feet long? Are you sure the issue was the valve?

On mine, the valve size would only affect the length of the heater hoses.

You can use a generic cable for the water valve. If your friendly local parts house doesn't have a 6 footer on hand, he can order one.

It isn't rocket science to shorten one that's too long, & the the wire is usually attached on both ends with simple "Z" bends that pass through holes in the arms.

One of the first bits of deferred maintenance I had to update on mine was replace the water valve & the cable. It got a little tricky on the water valve end because the control arm on the new valve didn't line up exactly as the original, but it's been working for 3 years now.

Hi: re:dash heat problem. We have a1995 38ft Monarch. I found that even when the heater was "working" that not enough heat was produced. On further investigation I found that the heater hose running from the engine (about 40 ft long) each plus was small 3/4 or 5/8 inch diameter. Since it was 10 years old and likely due for replacement anyway I replaced it with a hose 1" in diameter and added another heater in the front and one in the bedroom. Now when travelling in below freezing weather we are comfortable. I also put a booster pump in the waterline to the front to get more coolant delivered to the front heaters. Since the distance to the rear heater from the engine is quite short, and resistance to flow less than to the front I put a valve in the line to the rear heater and choked down the flow somewhat. Hope this might help someone. Fred Weeks

Hi Fred
We have a front rad on our Regency and so the hoses to the dash heater are not that long. The problem is in the vacuum control that switches the heat from footwells to defrost. It works well on defrost and not so good when it's supposed to be blowing heat to the footwells. But, in this really cold weather lately it seems ok, so since we are outta here for Phoenix next week (YAHOO!!) I'm leaving it alone for now.
Don