Is this a heater core or AC evaporator

[Sebulba]

Hello all,

I have removed a lot of the AC parts and am wondering about this part under the front window, kinda, on the passenger side.  Is it part of the heating system, or AC system.

If for heat, I will keep in case I ever open the valves a in back by the engine, but if part of AC I may lighten our weight a little.

Thanks
Seb

[Coach_and_Crown_Guy]

There should be both an A/C evaporator as well as a heater core for front heat
and defrost. Look at the input hoses and that will tell you if it's A/C freon or water
hose. The fittings are very different too.

The usual arrangement is to have the A/C evaporator, which will also have a
condensed water drain line, in front of the heater core to re-heat the air to the
thermostat demand temperature. That's what the main system under the floor
does for the whole interior. The dash system is probably similar. It will blow heat
as long as you don't have the driver A/C switch turned on. Then it will get cold.

You can shut off the hot water for the dash heater on the side wall under the
side window. When working correctly it's a very nice setup and can keep it cool
up front for the driver instead of cooking in his own juices with the large windshield.

You should be able to get all the info you need on this from the MCI service manual
which I'm sure you already have by now.... Right?
 

[luvrbus]

The core on the passengers side will be the AC evaporator it will have a tag use R-22 . The drivers heater core is tied to coach heat if you remove coach heat you have tie the 2 lines to the plumbing from the engine.The lines leaving the coach heat to the drivers heat are lot smaller and you don't get much heat without a booster pump inline BTDT 

[Sebulba]

The core on the passengers side will be the AC evaporator it will have a tag use R-22

Thanks Luvrbus, that's what it looked like to me, but in case it was something weird like a combination evaporator/heater core, I wanted to ask.  I have learned to ask, explore and analyze carefully before doing anything on this thing.  Assumptions can be devastating.

Anyway, ok,so if that is the evaporator,where is the heater core, I don't see one up front?

Thanks again

Seb

[luvrbus]

The heater core is floor mounted to the right of the throttle under the dash and is a bear to get to

[Sebulba]

The heater core is floor mounted to the right of the throttle under the dash and is a bear to get to

Ok, could that be under this floor panel?

Seb

[Glennman]

This is one of the areas in my 2002 MCI that I have yet to explore. For now, I turn the water valves off in the summertime but open them up when I need defrost. I haven't located the heater core yet, but I know it works. I need to replace the fans, as they are very noisy and run with sporadic fan speeds, but I do get good defrost. I also have left my bus heat system intact, as it still works. It was a lot of work to design around all the vent openings (heat vents and return air), but it works fairly well. I did however eliminate the bus AC system, as it had been defunct for quite a few years.

[Sebulba]

This is one of the areas in my 2002 MCI that I have yet to explore. For now, I turn the water valves off in the summertime but open them up when I need defrost. I haven't located the heater core yet, but I know it works. I need to replace the fans, as they are very noisy and run with sporadic fan speeds, but I do get good defrost. I also have left my bus heat system intact, as it still works. It was a lot of work to design around all the vent openings (heat vents and return air), but it works fairly well. I did however eliminate the bus AC system, as it had been defunct for quite a few years.

Thanks for that Glenman, I follow a lot of your build, since we are working on almost the same bus.  You have given me a lot of clues on how things work. 

Have yet to be brave enough to open those valves.  I tend to try not to open worm cans till I'm ready to deal with any consequences. 

Seb

[Dave5Cs]

Most are in the upright position like Clifford said under the dash to the right of the peddle in the middle. You will have 4 Duze screws there that you turn and the panel comes off. Unless someone has taken it out?