Wiring diagram needed for carrier air con unit

Being that old, it probably does not exist. The best you can do is get a circuit diagram, then plan you own locations and power wiring. Usually on the roof you will find a AC unit which requires 110volts ac, sometimes a 12 volt DC fan or two for kitchen or generally air cooling to exhaust hot air or circulate air. You may have a TV antenna on the roof needing RG 59 coax going to it.

Most air conditioners now are reverse cycle, which means that they can heat as well as cool. Cooling only units were popular many years ago due to the price difference for a reverse cycle. Today, the cost of manufacturing has dropped and it has resulted in cooling only units being virtually finished. I would suggest you get a local air con sales company to come to your house to measure up properly and determine what would be best. There are a lot of factors in installing air conditioning. IE/ The size of the house, the area it will be required to heat / cool, the amount of windows, types of walls, roof etc (Heat loading on the house) Roof and wall insulation etc etc.

Normally all air-cons carry an identifying label on the compressor unit. It has to by law state the gas used. On a split system this would normally be on the outside unit. Sometimes an additional label will be on one of the ends of the inside unit. Some units only do cooling - you need to check once you've found information. Check your remote control 'Mode' setting is correct - it should show a small 'sun' to indicate heating. A small 'icicle' looks similar, but means cooling. Then check temp setting is high enough to cause heating.

R- REd
C- Common
Y- Outdoor unit
W- Heat
G- Fan

http://www.corp.carrier.com/www/v/index.jsp?vgnextoid=9d087afdef677010VgnVCM100000cb890b80RCRD
Search this web site. It has lots of manuals. It is Carrier site.
Hope this helps. Wiring diagrams are hard to find but I know they are there if you input enough of the right info.
Hope this helps and be patient while you search.

You may have a durty evaporator coil do to a durty filter, the heat is cuting off by the limit control sensor

There is a low voltage wiring problem. Make sure your t-stat wire is in the correct positions and that you have not removed the jumper wire at the t-stat. There should only be 2 control wires leaving the airhandler and going to the condenser unit outside. Unless it is a heatpump. One wire goes to common and the other goes to the Y terminal. W terminal is for heat. The unit will cut off if you have the unit calling for heat and cool at the same time.

It sound like the heating sequecer maybe have gone bad on the fan coil unit that you have. You need to call the maintenance personnel that does the work where you live or a service company out to repair the unit because since y0u only rent it is their responsibility to provide youp with heat and if by chance that you have a heat pumo unit then you definately want them to get on the roof to fix the problem. Remember to always change oyur filter inside when ever you get your electric bill because even though it's theeir unit it's your electric!

This appears to be a Roof Top packaged unit. You will definitely need some help with this install. Your local Carrier distributer should have the installation curb kits and economizer etc.

Here is the most technical data I can find for this unit. Under the 50TFF section you will see the accessory dimensions. I hope this helps. (You will need adobe acrobat to read the file)

1.check wiring of unit.
2.check drain tray.
3.check u band of drain pipe.