Originally Posted by Midniteoyl
Usually a manifold source to the dash selector.. mine is a standard Dodge '80's push button unit...
I am talking about the under dash RV AC system, A few weeks ago I re-charged
the system and upgraded it to R-134A and got it making very cold air but no
matter what button I pushed air came out the defrosters hard with a trickle to
the dash vents or the floor vents
I traced all the little different colored plastic vacuum lines from each
actuator back to the control panel and untangling them as I went into one nice
and neat group, I had a white line, a green line, a black line and a red line
the green, black and red all ran from the control panel went to an actuator the
white just disappeared into a big hunk of foam and silicone. I carefully dug
around in there and found the white line was broken off coming from that pile of
goo going into the front of the rv radiator, once I cleared it out I was able to
pull about two feet of white line out from under the dash and then the issue
became, where does it go?
There is big black plastic ball with two diff sized nipples sticking out of it
and nothing attached to it. Whaddayaknow one of them is the perfect size to
connect the white line to. The other day I found a heavier but small rubber hose
that looked like a vacuum line but it was not connected to anything, sticking
out over the radiator. Did not know what is was for.
I found a vac source on the intake manifold that had a length of the same size
rubber hose with a plug in it. So I traced that rubber hose and it could almost
reach that black plastic ball, I cut off several tie wraps and it reaches now
and was a perfect fit. Now to find the other end, after some searching and
getting into some God awful positions to look, I found the other end under some
water lines and not connected to anything. I disconnected that hose with the
plug on the intake manifold and connected this newly found hose to the vacuum
source, perfect fit.
I started the motor, turned on the ac,. pressed the max button and air comes
pouring out of all the dash vent, I hit the bi level button and air now comes
from the dash vents and the floor vents, push the defrost button and air comes
out the defroster vents again, push the heat button and air comes hard from the
floor vent and decent from the dash vents
It works like it is supposed to work
The black ball is a vacuum storage chamber. After I turned the motor off I could
push all the diff buttons and hear valves opening and closing under the dash.
The white line was the vac source from the vac storage to the control panel