Don Updates his Air Conditioning

This page deals with the evaporator and heater, see this page for
pics and story of updating the compressor and drier of the AC.

My air conditioning worked fine for several weeks, and then one day when I returned from a drive, I heard a hissing noise up front. It turned out that the freon (the 134A) was leaking out at a joint where the new drier had been hooked up.

I had the mechanic tighten it down and re-charge the system. This time the cooling lasted over the weekend but was gone again by Monday. When the mechanic checked with his magic leak wand, he concluded that there was a leak under the dash -- the evaporator needed to be replaced.

After much agonizing, I decided to try to replace ALL of the under dash stuff with new. Dave, car 1279, had replaced HIS with a combo heat and A/C unit from Vintage Air -- he liked his and mainly had gotten rid of his big old heater box from under the dash. Dave's heater coils had been leaking, and several people said that 25 years of water sitting in the old heater meant that any day IT could spring a leak and make a big wet mess in the car. Many people suggested that re-using Dave's old evaporator was just a temporary fix since his was also OLD, even though it might hold pressure right now.

My plan was to try to install this myself -- probably a risky idea since my mechanical skill is right at about 0.

Removal of the Heater box -- There are 3 bolts on the firewall inside the engine compartment that hook into the back of the heater box. The two heater hoses are clamped on to pieces of metal pipe that come from the back of the heater box and poke into the engine compartment. Remove the hoses, plug up the ends of the heater hoses, unbolt the 3 bolts and wiggle the unit out from under the dash. I also removed the radio so I could get at stuff, especially the old heater controls, which I undid - marking the wires with tape for future reference.

View of the back of the box - 3 mounting bolts circled. The hose connections on upper left poke thru the firewall into engine compartment.

The heater box measures about 8 1/2 inches wide, 8 1/4 inches high
 and 8 3/4 inches front to back not including the bolts and pipes sticking out the back.

NOTES: -- there are a TON of wires going every which way under that dash. If you follow them one at a time, you can figure out many of their purposes. Based on a tip from Dave I removed the passenger seat, so I could lie down and work under the dash.

The heater is out - the holes where it went through the firewall are circled.

The one hose from the heater went up and hooked into the center above the dash.
That housing turns to slots across the car like a defroster

Once the heater box was out, and the heater controls, I proceeded on to the evaporator.

The circled things are two taped over outlets that are not used on the Glassic The mounting bracket is still on the right side

The evaporator and fan unit measure about 17 inches across
 (incl. the place to hook on the duct on the left) about 5 1/2 inches tall
and 10 inches front to back. The sticker says Frigette Corporation,
 and a serial number of 135044, but no model number

I was told that the new refrigerant was not a hazardous material, so I just loosened a connection and let what remained fizz out. The hoses from the engine compartment go through the firewall and are covered with a putty like substance. I picked that putty off so that the hoses could be pulled into the engine compartment an inch or two.

View of the drivers side end - the left side of the pic. faces the front of the car There is still some insulating goop near the fittings.
I removed the controls from the dashboard, and marked the electric wires as best I could figure out. The temp control has a soft metal tube that runs into the evaporator, and I poked the dial back through the dashboard and kept all of that hooked up together.

peeking in the air duct hose on the drivers side. Shows the coils inside and in the left upper corner of the picture is the drivers side mounting hole
The evaporator unit is held in place with just two bolts, one on each side of the unit, hooked on to brackets that hang down. The hoses, puttied into place through the firewall also held it up. Once the two bolts were removed, and I had loosened one of the hold downs on the hose under the hood, there was a tiny bit of play, so I could scoot the unit forward and reach up behind it with a wrench to disconnect the hoses. The smaller hose came off ok but the larger one was really stuck. I used some bolt release, and finally got two open end wrenches on it, one on the hose and one on the unit itself. I used a third wrench as a wedge between the two and finally it broke whatever was sticking it. That sucker was on there good, but as soon as it un-froze, it screwed off easily.

A nice view of the evaporator from the passenger side. You can see the fan at right, as well as the coils inside and the passenger side mounting hole along with the bracket that was attached.

View up under the dash toward the passenger side. Circled is one of two drain hoses that left the bottom of the evaporator and went through the firewall and pointed toward the ground. The were dried out and broke off, and will have to be replaced.

Above is a tough angle to figure out. I was laying on my back with my head under the dashboard toward the front of the car - looking straight up. The metal across the center is the cable and mechanism for the passenger wiper. The black hose is one of the windshield washer hoses. Now is the time to add lighted washer nozzles if desired.

Removing the dashboard.

Actually, removing the dashboard would be a task -- just look at all of the things that are poking through it! I decided to loosen in in case I wanted to get inside from the top of the dash, or pull it out a bit for more working room. Taking the dash loose is pretty quick and easy. That is sure the best way to change out the gauges, which is something that I may want to do also.

Loosening the dash should make it easier to re-connect ducts.
First, remove the trim piece that goes all around the dash and down to the floor on each side. In my case, it was held in place with screws and trim rings. After removing the trim, you can easily see the screws which go around the top of the dash and hold it in place. Remove them (the second screw from each end was longer than the rest) -- and then only the emergency brake handle is fastened to the dashboard. Take off those two nuts and bolts, and the dashboard is free - except for all of the electrics poking through it. I plan to replace the idiot lights with LED's, once I find some that fit in a 1/2 inch hole.

View of the back of the gauges. I don't know WHY there are so many wires in there -- I thought that there would be one hot wire, one ground and one for the light. I have yet to figure out what they all are. The left of the pic is the passenger side of the car.

A fellow Glassic owner put me in touch with Jon, from Tampa, whose father owns Nostalgic Air in Ocala, Florida. Jon doesn't have a storefront, but travels to shows and makes house calls in the area. In conjunction with his father's shop, they also can provide mail order, so I will document my experiences with them.

Jon saw the pictures of the old parts and brought a unit to the house. It was heat and air and costs $250. Once he got here, we learned that there WERE options to be decided.  One way to install this was with a knob that opened and closed the heat hose, like the original. Also available was a billet rectangular control panel - there was no extra cost for that, but the electrically operated heat valve for the heater hose was not in the box and a knob cover was missing for the control panel. 

The whole unit looked about the same size as the old evaporator. In the unit that he brough, the heater and air conditioner outlets were on the wrong side, and Jon had to take it back and order one the other way around.  The unit that I wanted had the air conditioner fittings on the driver's side and the heat lines on the passenger side. What he brought was the reverse of that.

He left the billet dash panel with me (there is a template included since the dashboard needs to have a rectangular hole cut in it.  I will wait until I have the evaporator in hand before cutting the dash.  Another option ($30) is an electric valve that switches on the duct work to the defroster setting on the switch.  A free option was that he would provide a Y pipe for one duct and have the defrost on at all times. I decided to get the valve so that the defroster would work correctly.  The control panel is pre-wired, and I have been assured that anyone can do this. We shall see.

 click to see more about air conditioner upgrade