Forum Discussion

louie992's avatar
louie992
Explorer
Feb 14, 2016

Cold Coach While Driving

Hello all. New to DP ownership and have an issue. I've read several posts on cold weather camping, but I have a different issue that I'm not sure about. We recently drove from Nebraska to Florida for a few week stay in our new (used 2006 Mandalay 42ft), January to mid February. The outside temps were quite cold, generally low teens for most of the trip. I was running the drivers compartment heat, as well as, the coach furnace. Unfortunately is was quite cold up front requiring me to wear a jacket and even gloves at times. It was also fairy chilly in the living compartment of the coach, however the rear sleeping area was very toasty due to the furnace and engine heat. Is this normal due to the large windshield? I don't seem to have any major drafts up front, but did notice a pretty good draft coming in around the refrigerator. I plan to have the shop check that out and seal up this spring. Lastly, how forceful should be/is the front drivers heat blowing for others of you with similar rigs. I am wondering if I might have a fan going bad. On high, it feels like it's blowing as hard as the fan set on low/medium in our Escalade. Is this normal with a DP? Will we have the opposite issue this summer when we head out West with family for a summer vacation? Thinking Grand Canyon, etc. Any thoughts and comments are appreciated. Thanks!
Class A
  • w4phj's avatar
    w4phj
    Explorer
    Feb 14, 2016
    My dash heat works well but I also use the propane cabin and bedroom heaters as needed.
  • MrWizard's avatar
    MrWizard
    Moderator
    Feb 14, 2016
    several things to check
    one is operation of the heater valve, make sure it is open
    pop the front hatch, find the back of your heater core
    valve is in the hot water line

    ALSO some coaches have a hot water cut off valve near the engine
    that come into play when using the A/C its electric, also look for a hotwater shut off or manual bypass valve
    if this valve does not open you will get very little heat from the heater core
    our cumins diesel is smaller than your engine, and our heater is very toasty up front

    some RVs your size have (2) furnaces, check for that and IF so it might not be on
  • Joatha's avatar
    Joatha
    Explorer
    Feb 14, 2016
    Are you sure your front house heaters (not the chassis heaters) are all on?

    Given that you have a DP, I wouldn't be surprised if you had a 2 zone (or more) system. Make sure you are getting air out of all your vents - and that its warm. Make sure that you don't have to turn on the front zone in addition to the rear one.

    My coach has 3 zones - bedroom, bathroom, and living area. All 3 have to be on to get heat to all of them. Granted, I can usually turn on the front and rear and be fine. But, in freezing conditions, I may have to run all 3.

    What kind of heat do you have to heat the coach? Is it a propane furnace (sounds like this is the case)? Aquahot? Something else? Make sure you have just 1 before taking other measures - there may be a second to heat the front of the coach.
  • Trackrig's avatar
    Trackrig
    Explorer II
    Feb 14, 2016
    If you're going to put it in the shop, have them check the hot water line going to the front to see if it's in some sort of protective wrap, or if it's out there by itself where all of the cold are flowing underneath the DP is sucking the heat out of it? If it's not protected it, they need to insulate it with something such as the black foam pieces you use in a house to keep hot water pipes hot. Use a bunch of ty-raps on it.

    How did you have the heater air direction set? Was it mostly on heat or on defrost? Granted you have to keep the window clear to safely see, but divert as much of the air to the floor or dash vents as possible.

    And I'll be you have more fresh air coming in through the front end than you think you do. On my DP, there is no insulation under the dash - just the bulkhead itself. We have a very good heater, but I'm still thinking of using foam insulation under the front cowling to seal up any air leaks and provide more insulation.

    Bill
  • bobtucker's avatar
    bobtucker
    Explorer
    Feb 14, 2016
    Try putting a shower curtain behind the drivers seat when traveling. Helps with AC and heat. A spring loaded shower rod and a set of closet brackets (unpainted) from lowes/D+HD will work wonders.
  • jplante4's avatar
    jplante4
    Explorer II
    Feb 14, 2016
    It's not uncommon for the heater control valve to be screwed up in some way. Either the valve is stuck or the cable is broken. Some heaters have a bypass and required the heater valve to be all the way open before you get heat.

    I had one gasser where a previous owner installed a manual heater valve. To get more heat, you needed to stop, open the front and twist the valve.

    In both my coaches I replaced the heater valve with an electronic one from Thermotion. If you have a 2 port valve and a bypass, get a four port valve from Thermotion and replace the bypass with the valve.
  • Ivylog's avatar
    Ivylog
    Explorer III
    Feb 14, 2016
    Would not blame it on the large windshield... more likely air leaks up front and the heater valve. How hot was the air from the vents and was the heater on recirculate... no outside air? Replacing the motor driven heater valve with a manual one is good, especially for increasing the AC in the summer.

    Buy a IR temp gun (Harbor Freight $15) and see how hot the heater hoses are at the heater and either side of the valve. Closing the back of the MH and the heater vents so less area and more heat to the front may help.
  • Kayteg1's avatar
    Kayteg1
    Explorer II
    Feb 14, 2016
    Sounds like you have some coolant flow problem or undersized heater core.
    Usually front heat can keep everything pretty cozy even with big windshields.
    Than I don't have much experience with 10F temperatures.
    Still measuring temperature of air coming from front heater would be good starting point.
  • johnsonbert's avatar
    johnsonbert
    Explorer
    Feb 14, 2016
    On ours, we get pretty sufficient heat for most conditions we have been in while driving. During the times when we did not, I ran the front aqua-hot zone and used a small portable fan to blow a little more heat up towards the front. That seemed to work for us. You might make sure that your heater hoses at the front are really hot, I have seen some units with shutoffs back at the motor, or in the front at the heater core, or your heater control valve may not be opening all the way top allow full water flow. These are some possibilities to check out, hope they may help. Happy Trails Bert

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