Front Ceiling Cover AC Vents

[Bob125]

While driving (and the slides are in), the slides cover the A/C outlets thus diverting the cool air to the top of the slides.  I think the AC would be more efficient by directing the air into the living space.  Our coach (2009 Beaver Marquis) has a hard time keeping cool while driving even with the genset and all 3 ACs running.  I am thinking about covering the 4 AC outlets and drilling new 4" holes and install 4 round vents that will direct air down thru the cover into the living area.  The material on the cover has a foam backing.  My question is how will this material respond when I drill a hole into it?  When I install the 4" round vents will the cover compress back like the other original cover looks?  I'll be very careful with the initial cut and use a very sharp knife.  Then I'll use a 4" hole saw.  I'm hoping the vent cover when screwed on will compress the cover material back down like the other detail.  Trying to keep it as professional and factory looking as possible.  Thanks in advance for any insight.  Bob...

 

Pics attached are:

    Front AC Ceiling Cover

    Ceiling Cover blocked by Slide when in

    Ceiling Cover material detail

    Back of ceiling cover 

    Potential new vent locations

    Pic of vent

[Hypoxia]

What else have you done?  First, that filter is restricting air flow.  You need a non-restrictive filter like the $2 ones.  Have you made sure the A/C units have the correct foam seal between the cover and the unit and that they are sealed with metal tape and not leaking air?  Have you checked for leakage on the ceiling where the A/C units flow into the ducting?  There was a thread here recently that discussed the large improvements made by doing those things.

[redstickbill]

Bob, coils

Can you compress the ceiling cover with your hand?, if so the vinyl is backed by foam and you could do what you are thinking of. As Hypoxia mentions those filters are restricting some of the air flow. I have had to reseal the air flow between the A/C return/exhaust and the ceiling to stop any air flow escaping into the ceiling. Also there should be a foam piece separating the air return and exhaust, this prevents the cool air from being drawn right back into the air return. Have you cleaned the evaporator coils in units. I have no problem keeping the coach cool while driving with the A/C's

Bill B 07 Dynasty

I should have proof read before posting, forget the coils after Bob.

Bill B o7 Dynasty

[Steve P]

Your A/C does not have the slider (with a vertical tab)  that can be used to divert air from the coach vents to a single vent on the unit itself?  When diverted, cold air blasts downward from the unit (which is of course centered left and right).  Primitive, but effective... 

[Dennis H]

I would spend my money of 'fixing' what you have, otherwise you're going to be disappointed. Your A/C units should adequately cool your coach. I was only using the front and rear in 120 degree Arizona heat and didn't have a problem. My guess, as mentioned, is your filters and/or properly sealing the units on the roof. Fix what you have before throwing good money at a fix that won't cure your issue. Just my 2 cents......Dennis

[vito.a]

Wow, you have one of the last great Monaco/Beaver coaches!

I agree.  Get rid of those filters.  

Then try reversing two of the existing black vents inward.  

How is your dash A/C?  Replace the dryer, evacuate it and properly charge it and it will help the driver and passenger area a lot.  

 

[MrAmbassador]

Unless modified, your cool from each A/C (down draft) is flowing back in directly to the A/C return. As mentioned above there should be a leak free seal between the two cavities. I suggest returning all three A/Cs back to its original configuration (which includes foam filters). 

[Bob125]

Thanks for all the ideas.  I just switched from foam to residential filters.  So, I will switch them back.  I did not realize they had more resistance.  Previously, I have inspected all the ducts and vents for leaks into the roof area and bad seals.  I've corrected anything that looked like a leak.  I've also have modified the supply area to help the air transition into the ducts smoother and made sure there is no return/supply air mixing (see pictures).  That helped increase air flow some out of the vents.    The coach cools great while parked and I have no concerns while parked.  But, while driving on a 95 degree day, it's approx. 83-85 inside with genset and all 3 AC's running on High fan and set on 60 degrees.  I have remote temperature probes and have measured the return and supply temp differences while driving and they all keep around a 20 degree differential.  I'm not expecting 60 degrees, but feel it should be able to keep 75 degrees.  It seems the heat load while driving overwhelms the cooling capacity.  I've checked for leaks and found none.  I thought possibly some type of exterior airflow around the condensers was impacting it's effectiveness but they hold a 20 degree supply/return differential.  I have added more insulation to the front cap and planning on adding more to the genset area, backs of cabinets, engine compartment, possibly the bottom pans, etc. 

The ceiling pad does have the underfoam that compresses.  I'll insulate as much as I can next before covering up the 4 current vents and cutting new round vents that will direct the airflow out to the living area.  Thanks for the help, I will definitely change back to foam filters.  

Any other ideas will be greatly appreciated.  These are 15,000 BTU Dometics, original in 2009.  This hot while driving issues has been this way since we bought the coach new in 2009.