How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Rick Mather Your Own Question
Rick Mather
Rick Mather, HVAC Technician
Category: HVAC
Satisfied Customers: 3634
Experience:  35 years experience, HVAC
12095340
Type Your HVAC Question Here...
Rick Mather is online now
A new question is answered every 9 seconds

I have a York Diamond 80 HVAC system. I was trying to change out the t

This answer was rated:

I have a York Diamond 80 HVAC system. I was trying to change out the thermostat to the new WIFI Honeywell one. My old thermostat was ran off 4 wires and 2 AA batteries. Green wire to the G, Yellow Wire to the Y, White wire to the W, and Red wire to the RH with a little jumper wire going from the RH to the RC. When traced into my attic, it is hooked up with the Yellow to Y, Green to G, White to W. The red wire goes to the C (which i think is common). Then there is a separate 5 wire loom in the attic which i think runs outide to the condenser and the fan that makes the air cold. It only uses the red and yellow wire. The Yellow wire is hooked up to the Y, and the red wire is hooked up to a fat yellow wire that runs to a float which i think is a safety valve that will raise if i start overflowing. It goes from that float and connects to the R. So i have 2 yellow wires on Y, 1 White wire on W, 1 fat yellow wire on R, 1 green wire on G, and 1 red wire on C. The Honeywell thermostat needs to have a C -common. It gives a few ways to wire. I tried using the current 4 wire configuration and at the thermostat keeping a similar wiring pattern. Yellow wire to Y, White wire to W, Red wire to R (with a jumper from R to RC), and a GREEN wire to C - COMMON. Then in the attic I followed directions and kept the Yellow to Y, White to Y, Red to R, and Green to C. Then i ran a jumper line from Y to G. This would not click on my unit outside the house that creates the cold air. All i would get is my blower on with room temperature air. I tried a different option. I had a blue wire that wasn't being used in my bundle. I read that it should be used as the common. So i wired the Blue to the C, Green to G, Yellow to Y, White to W, and Red to R with a jumper between R and RH. Up in the attic I did the exact same thing. I left the yellow wire and the red (big yellow) hooked up to the red. I tried moving the Red wire to the R, and then alongside the Blue wire in the C. I can get the fan to blow but the outside unit will not click on. My thermostat will not trigger the outside unit like it should. I don't hear a click when i drop the AC temp below the room temp like i do on my old thermostat. I reinstalled my old thermostat just to make sure all my parts are working and I'm having no other issues. I am assuming that my wiring is wrong event though I've tried both ways that Honeywell says to wire it and even tried some trial and error ways of my own. I tried keeping the wiring that works with my old thermostat and then just added the Blue Wire to the C on both the attic and thermostat but it still would only engage the fan and the not allow the unit outside to kick on to get the air cold. I would appreciate any help you guys can give me. The thermostat is the Honeywell RTH6580WF


Rick Mather :

This part is good "Green wire to the G, Yellow Wire to the Y, White wire to the W, and Red wire to the RH with a little jumper wire going from the RH to the RC." Now you need common wire from the transformer that is feeding power on R terminal.

Rick Mather :

Hope you did not put Red On terminal C if so check transformer secondary for blown fuse if so equipted

Rick Mather :

Please advise if you need more assistance

Hi my name is XXXXX XXXXX your in the capable hands of Rick and i must agree with his answer. unfortunately you have come back on our question board. I wonder if there is anything else you require. If yes please do not hesitate in replying back. If you would like to rate Rick for the quality of service he has provided then he will get renumeration for his efforts.

Of course if you are unhappy just ask and we can cancel this question for you.

Best regards

Brian
Customer: replied 4 years ago.

http://www.youtube.com/watch?feature=player_embedded&v=g5UXw6QhcCQ This is the video that i followed. However, because my previous thermostat had a red wire on the C terminal, i moved it to the R terminal and then put the unused blue wire on the C terminal


 


You said, "Now you need common wire from the transformer that is feeding power on R terminal." Im not sure where that is at or what exactly that means. I made the extra Blue Wire my common wire. It is current at the C terminal on my thermostat and the C terminal in my attic. Should i connect it to the R terminal instead of the C terminal in my attic? Is this what you mean? Or do i need to find an extra wire somewhere and connect it to the C terminal in the attic along with the blue wire coming from my thermostat.

As Rick has assisted you up to now i will let him finish the question. but i will say that the connections in your attic are not always what you have in your system. The common in your attic may not be connected to the HVAC system at all which will mean you have to run a cable from the attic to the common in your system.
as i stated you need common from transformer which will be in air handler and or furnace which should have terminal C or if it does not you will have to make connection to transformer itself
Rick Mather, HVAC Technician
Category: HVAC
Satisfied Customers: 3634
Experience: 35 years experience, HVAC
Rick Mather and 2 other HVAC Specialists are ready to help you

Related HVAC Questions