1997 American Dream 2016 09 06

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We were at the races at Gateway Motorsports Park where it was VERY hot and humid. The front and rear ceiling A/C units are the same unit, but the rear unit has never seems to blow as hard as the front.

Between rounds I decided to take a look and removed the grill on the rear unit. I found that the filter was clogged and when we removed the filter that unit picked up at least 50% in air movement.

I pulled the grill down on the front unit and found that that filter was spaced down from the A/C unit because of the mirror on the ceiling in the front of the Motor Home.

ceiling-ac-grill-spacer-dsc_0636This is the grill in the ceiling at the rear of the Motor Home

 

 

 

 

ceiling-ac-grill-spacer-dsc_0563With the grill removed, I found that the center section of the roof A/C unit protruded beyond the ceiling and was crushing the filter. This only allowed the air to come into the A/C unit through the holes on either side of the protrusion (which holds the evaporator of the A/C unit)

 

 

 

ceiling-ac-grill-spacer-dsc_0564Air could only enter the unit in the areas marked. The difference with the front unit is the grill and filter were held away from the unit by a good inch by the mirrors, rope lights, and roof console in the front of the Motor Home. So what I need to do is space the filter down so that air can pass through the whole filter rather than the small areas available now

 

 

I gave it some thought and came up with the idea of building a frame to hold the grill away from the A/C unit. I ripped up a 2X4 to give me some ¾ by 1 inch strips. I gave the frame about a ¼ revel as making it flush would not look as good (at least I think so)

ceiling-ac-grill-spacer-dsc_0600                            ceiling-ac-grill-spacer-dsc_0601

I used some wood glue and shot some pin nails into the corners, and then to strength the corners added some small blocks of wood. These blocks of wood serve two purposes, strengthen the frame and they allow me to drill the corners so that it provides a chase for the screws to go up through into the original holes in the ceiling. These screws will now align the frame to the grill and hold the frame and grill to the ceiling using the original holes for the grill

ceiling-ac-grill-spacer-dsc_0602                           ceiling-ac-grill-spacer-dsc_0605

To try and give the frame a little class I rounded the corners using the same radius on the grill

ceiling-ac-grill-spacer-dsc_0609                           ceiling-ac-grill-spacer-dsc_0612

Test fit using the holes in the corners of the frame to align the grill

ceiling-ac-grill-spacer-dsc_0614                           ceiling-ac-grill-spacer-dsc_0613

So now I need to figure out a way to hold the filter up against the grill and away from the A/C unit to allow the A/C unit to drawn air through the whole filter. I drilled some holes the size of some TIG filler rods and by bending them slightly fed them into the holes to create a grid to hold the filter between the frame and the grill

ceiling-ac-grill-spacer-dsc_0615                          ceiling-ac-grill-spacer-dsc_0617

ceiling-ac-grill-spacer-dsc_0618                          ceiling-ac-grill-spacer-dsc_0619

I did not want the rods to vibrate so I used some wire ties to hold them together. I stained the frame to a color close to what is in the Motor Home. I was pressed for time as we are leaving tomorrow for a race in Michigan so I only got three coats of varnish on the frame before I had to mount it

ceiling-ac-grill-spacer-dsc_0621                          ceiling-ac-grill-spacer-dsc_0633

ceiling-ac-grill-spacer-dsc_0637What a difference! With just the rear unit on now we get air out of the very front duct in the ceiling. You should check you’re A/C filters to make sure they are clean (mine are washable). This simple change has made a HUGE difference in the amount of air that comes out of the ceiling vents.