Low Dash Heat

[Greg2]

I posted in the Class A forum about only warm heat coming from the dash. Both valves back near the engine are open, air control set to recirculate. Someone asked if I had a 'bus pump' inline to pump coolant thru the heater-I don't know, do you?

Along the same lines, would bypassing the engine and hooking up a LP tankless water heater with a pump provide more heat than what I am getting now? The Onan is LP powered so i have a 2nd LP tank aboard.
I'm thinking about putting the water heater near the front and eliminate the '40 miles' of hose going to/from the engine and the associated heat loss.
Not thrilled with the idea but even less thrilled with running the furnace on the road for 3 days or so to get to our Florida park. Happy wife, happy life.

What say you?

[RobbyII]

Have/had the same problem. Bought a extendable curtain rod (8+ft.) and fairly heavy drapes.Used the same hangers that are used for closet rod. When cold or hot out put up bar with drape, close drape (Velcro) and heater warm enough for cold and air cold enough for hot. We did get it very close to ceiling and hangs to floor. Only been cold enough once, crossing Nevada in Janruary ran generator and space heater in front area. With curtain right behind seats the heating area is reasonably small.

[Greg2]

Originally Posted by RobbyII

Have/had the same problem. Bought a extendable curtain rod (8+ft.) and fairly heavy drapes.Used the same hangers that are used for closet rod. When cold or hot out put up bar with drape, close drape (Velcro) and heater warm enough for cold and air cold enough for hot. We did get it very close to ceiling and hangs to floor. Only been cold enough once, crossing Nevada in Janruary ran generator and space heater in front area. With curtain right behind seats the heating area is reasonably small.

I have used the curtain idea on our old gasser class A, but this air is barely warm at the outlet, not near enough to heat even your hand on the steering wheel, let alone a small cabin from a curtain forward.
Good idea though.

[CJ7365]

Originally Posted by Greg2

I have used the curtain idea on our old gasser class A, but this air is barely warm at the outlet, not near enough to heat even your hand on the steering wheel, let alone a small cabin from a curtain forward.
Good idea though.

Are the hoses going into the heater core hot?

Maybe a plugged heater core?

[Old Scout]

Either a plugged heater core [internal water or external air flow].....or the "h-valve" heater control valve that feeds hot water to the core is not opening....

[House Husband]

You heater problem is not a design issue, it's a component failure.
Many DP have good dash heat and A/C.
In fact, you have one of the best. It's manufactured by Denso and has a blend air door, no water flow control valve and no vacuum controls. All the doors are electrical servo controlled.
Is the blend air door functioning properly?
Is the heater core restricted?
Is you engine running at the proper temperature?
I have the same HVAC system in my gas bounder and the heater core is original and works well.
Why not get it fixed properly?

Richard

[dpinvidic]

I am actually bringing my coach home tonight. I will measures the temp of the heater hose going into the firewall.
I had made the assumptions that the coolant was cooling done by the time it got from the rear engine up to the firewall.

Mine is not has hot as I would like, but it begins to work a lot better when I start climbing a hill and the engine temp goes up about 15 or 20 deg.

I will post hose and air temp for comparisons.

Dan

[erniet]

While driving down the road, I have fairly good heat coming from the dash ducts.

But when I come to a stop light or pull into a truck stop, very soon the air temperature from the dash ducts drops significantly. I have the same thought, 40 foot of heater hose cools down, but that's only a guess. I do not see the engine temperature gauge drop, but I guess my water pump would be producing less gpm and thermostat could partially close to keep the engine warm and care less about the driver.

I would like an answer or solution to this problem also. Thanks

[Greg2]

Originally Posted by RLS7201

You heater problem is not a design issue, it's a component failure.
Many DP have good dash heat and A/C.
In fact, you have one of the best. It's manufactured by Denso and has a blend air door, no water flow control valve and no vacuum controls. All the doors are electrical servo controlled.
Is the blend air door functioning properly?
Is the heater core restricted?
Is you engine running at the proper temperature?
I have the same HVAC system in my gas bounder and the heater core is original and works well.
Why not get it fixed properly? Richard

It turns out I may not have a problem after all. Last year we departed ahead of the cold weather, the year before is what I recalled.
This year it looks like it will be Jan. before we can head south. I just went out and started her up and at a fast idle got 173f on my cheapie hand held infrared thermometer both going and coming out of the heater under the 'hood.' Knowing that it will be hotter when being driven, I think it will be just fine.
Being new to me then, I may have not had the shutoff valve turned on, or may have had the recirculate button set for outside air. I don't know.

At any rate, I know what to do if it fails to perform. Thanks for the ideas and help.

[dpinvidic]

I measured roughly the same numbers.
Engine temp was 181 when I got home and at idle.
IR gun showed 162 deg temp on the heater hose at the firewall.
I can see more heat loss if traveling at 60 mph even if most of the hose is in the basement.
My last 7 ft of hose has foam insulation.

The air temp coming out of the dash was 138 deg. using re-circulation setting.
The ambient temperature was 68 deg.

On a side note, I changed the engine oil...boy, 15w40 oil sure pours slowly at that temp

Dan

[jdoc]

Dan, the next time you change your oil if it is cool or cold put your oil where it can get warm and then pour it in.

Jerry