Response from Nilo :
Originally Posted by trollmastergeneral
I was trying to determine why the wires were ever taken apart.Was the unit not working and a service person came out or did he just notice one day the heat pump did not work? Is this a heat pump with electric back up heat. how many and what colors are comming from the thermostat
(1)I don't know why the other guy took the thermostat wires off. He was not a service person that I know of, just someone who got the heaters on the furnace to run when he did whatever he did. (2)Yes this is an electic furnace with as heat pump that was added on later. (3)The furnace has 4 low voltage wires coming out of it. Red(from transformer), Yellow(to the other side of the transformer), White (to the sequencers), and Green (to the blower relay). These I have traced to their connections on the furnace.
I don't know why he took the wires apart. when he could have run the funace on Emergency heat, right? Below is some info about what I have learned after going back today.
That information begins here.
Here is what I think:
I believe that the control board on the outside unit is bad. I can get the system to run by jumping the red and orange that come to the outside unit, where I jumped them to the contactor on the outside unit. I know the Orange wire goes to the reversing valve, but It read 24v. when checked against the Red wire coming out to the unit outside.
The heap pump will run on heating with these jumpers on. These jumpers by-pass the control board. The outside unit will not run through the control board.
NOTE: I think I have some of the functions of the wires on the thermostat figured out.
Green bower relay
Oange=the reversing valve
Yellow = contactor
Black=?? (could this be the common wire?)
Brown - (Emergency heat?)
Here is what I did with the thermostat wiring:
I connected the thermostat wires color for color to the wires going to the outside unit. Then I hooked the RED wire form the thermostat to the RED wire from the furnace transformer (to get 24v. to the thermostat). I hooked the Brown wire from the thermostat to the WHite wire on the furnace (this white wire traced to the sequencers. The Brown wire must operate through the lower mercury switch on the thermostat). The GREEN wire on the thermostat I connected to the Green wire to the furnace (blower relay), and hooked those two Green wires to the GREEN wire to the outside unit. The YELLOW frunace low voltage wire (the transformer common wire) I hooked to the RED wire going outside. All this came about after a lot of trial and error.
When I turned the heating on, the outside unit came on, but when I removed one of the jumpers outside from the thermostat wires that I had jumped to the contactor, the outside unit stopped. So I left the jumpers on and it would run through the thermostat. By doing this jumpering, I by-passed the circuit board on the outside unit. Thats why I think this board is bad.
Here are the furnace and outside unit and thermostat model numbers: [COLEMAN
ELECTRIC FURNACE model - EB17B], [OUTSIDE UNIT model - COLEMAN
BRHQ0301BB], [THERMOSTAT model - EVCON
This heat pump was added on to this furnace, it did not come with the furnace originally.
If you can't use this info, just email me firstname.lastname@example.org
, and I will send send back the diagrams that I have obtained since you last reply. Thanks for all your trouble.........nilo