Cab heat

Desert Captain wrote:
I can deal with the dust as you do but those damned washboards get old fast.

We do what we have to do to get at the rocks!

Our worst case so far has been around 25 miles each way at 7-10 MPH on extreme washboarding in Central Oregon. The boondock camping way out there was priceless, however ... wonderful serenity and spectacular night skies - remote desert camping at it's finest.

We've had to do some extra things such as install special cabinet door latches to keep things in their place. The "go fast on the washboards to smooth them out" technique doesn't work with Class C motorhomes - at least not at any speed I've been able to determine with our small Class C on an E450 chassis. However I haven't tried it yet with the Koni FSD's in the rear.

IF you laminate a moving blanket to your curtain, it WILL stop the heat leak.

It works well in the cold too.

Tim

Good info Phil, thanks. Frankly my days of driving down dusty roads in the C are down to just about zero. I can deal with the dust as you do but those damned washboards get old fast.

:C

Desert Captain wrote:
Once again Phil we agree. I too utilize the Mix function for the distribution of cold AC air. I also do not see how the air dam pictured above does anything but block the flow and increase resistance but happily my 2011 E-350 chassis has none of the heat issues previously discussed.

Usually by the time we reach the CG, check in and reach our site the engine has been operating at very low RPM with a fair amount of idle, for a while and most of the engine heat is gone. Never felt the need to prop open the hood but I'm sure that would enhance heat dissipation.

There is only one situation in which it might not be wise to use the MIX ventilation setting for the cab air conditioning in a Class C rig in warm weather - when traveling on dusty desert roads!

The MIX setting feeds the air conditioner with air from the outside. When traveling in our Class C in the desert in warm weather we always close everything up except for one powered roof vent with it's fan set to "AIR IN" so as to maintain a slight positive pressure inside the entire rig that will prevent dust entry from any openings/cracks in the rig.

Creating positive interior pressure from a powered vent on the roof keeps the small amount of outside air required by the fan from originating down low where road dust is coming from. The amount of air drawn in by the roof fan will be very small since it's only outlet will be via any openings/cracks in the rig.

In this situation we always run the cab air contioning in RECIRCULATE mode - thus preventing outside air from entiring down low in the front of the vehicle where the ventilation opening is.

This trick works like a champ in dusty conditions ... I hate cleaning up the rig any more than necessary after trips! ;)

(Some offroad TT's in Australia even have a positive interior air pressure system built in to help keep dust out.)

I open the hood, but then people keep asking if I need help fixing my RV.

Tyrone,

Thanks for posting the picture.

I think it may work be created a vacuum behind the air dam and sucking the heat down and away from the engine compartment.

Anyone else have a suggestion as to how it works?

I do not know for a fact how the air dam works only that it does. What I think it does is direct air that normally just flows along the bottom of the engine up into front of the engine and behind the radiator. This air then has to go some where and that would be along the top and side of the engine flushing the heat out.
But then again I am not a air flow engineer not have I run it thru a wind tunnel to get all of the figures and flow charts.All I know is it works on my RVand that is all that matters to me.

I am not trying to sell it or make money off it just sharing what I found that cured a problem I had.
If you do not have the problem great for you.
The original poster is complaining of ambient engine heat sink issues after he parks.
I would love to know how redirecting AC flow inside the cab while driving is going to help with a heat sink problem on the outside of the cab after he parks?

That is a problem that he has and if you do not have it telling the original poster you do not have that problem is not helping him one bit. Bravo to the posters that talk about opening the hood and putting a fan on the engine they understand the OP's problem they have experienced it and they are sharing what they do to solve that problem.

Many issues only effect certain model years.
I am smart enough and courteous enough not to tell someone that is experiencing problems with there V10 why should you be having that problem since I have never experienced it with my 460.
Some folks on here would state they never had a problem in switching between front rear gas tanks even if they only had a single tank.
To sum it up I have had the experience that the OP is having and I shared something that worked for ME to solve the problem.
If you are not experiencing the problem then how are going to help the OP with his problem by telling him that you do not have his problem?

Once again Phil we agree. I too utilize the Mix function for the distribution of cold AC air. I also do not see how the air dam pictured above does anything but block the flow and increase resistance but happily my 2011 E-350 chassis has none of the heat issues previously discussed.

Usually by the time we reach the CG, check in and reach our site the engine has been operating at very low RPM with a fair amount of idle, for a while and most of the engine heat is gone. Never felt the need to prop open the hood but I'm sure that would enhance heat dissipation.

:C

I've tried what pnichols is referring to with the cab air in mix mode and it works fine that way. DW usually complains of cold feet on long trips. Sometimes have to start out on normal air settings if been locked up in sun shopping, hiking, or etc.

To the OP: For stopping to camp and not wanting so much of the heat from the huge engine/transmission mass adding it's heat into the coach interior ... I open the hood for a couple of hours and also immediately block off the cab area from the coach area. Winnebago supplied stock curtains for blocking off the cab from the coach. We also block off the cab for more efficient winter heating of the coach area and more efficient summer cooling of the coach area from the roof A/C when camped.

To TyroneandGladys: From you photo .... I'm scratching my head as to what are the physics going on such that the piece rubber/plastic/metal(?) dam hanging down behind the front bumper can keep the engine area cooler and hence keep the cab floor cooler?

It seems to me that it woudd kindof do the opposite .... BLOCK outside front air flow from going both up into the engine and underneath the coach flooring to help cool both when going down the road - plus maybe create a bit more overall frontal air resistance so as to reduce gas mileage.

For some reason, our Ford E450 Itasca Class C came from Winnebago with straight-forward simple metal heat shields between the exhaust piping under the cab floor and the cab floor. Our cab flooring does not get uncomfortably hot going down the road. In hot weather we also sometimes run the cab ventilation system in MIX mode with the cab A/C fan set on one of it's two highest speeds. In MIX mode there is no air conditioned cold air coming out of the cab vents blasting chest-high right into the driver and passenger. All of the cold air comes only out of the windshield defrost outlets and the FLOOR outlets! This keeps the cab flooring extra cool, plus also keeps cold air out of your face. The chilled air coming out of the defrost vents rolls up along the windshield and gently sinks down around the driver and passenger such that we feel no chilling air blasting our faces, chests, or arms. It makes for a great overall comfortable temperature in the cab with no hot floor (... ours doesn't get very warm anyway due to the shields) and no cold air blasting directly on you. (I discovered this MIX dash ventilation setting air conditioning trick completely by accident several years after owning our Ford based Class C ... as I assumed that only HEATED AIR would come out of the windshield defrost vents. With the temperature knob in the blue region cold air comes out instead - along with cold air coming out onto your feet!)