Thermostat wiring help


  #1  
Old 12-14-20, 08:36 AM
P
Member
Thread Starter
Join Date: Feb 2014
Location: United States
Posts: 27
Received 0 Votes on 0 Posts
Thermostat wiring help

I have a typical A/C heatpump condenser unit here in Arizona...ever since I installed my Sensi thermostat, the heat has never worked.
After many years (haven't needed it), I really want it to work now.
A/C works fine, fan works fine. If I put it in heat mode, the blower motor runs, but the condenser unit never turns on.

Here is the wiring on the board at the condenser unit and the wiring at the thermostat. Anybody know if some wires are mixed up somewhere?

Would be a great help!



 

Last edited by PJmax; 12-14-20 at 10:43 AM. Reason: resized pics
  #2  
Old 12-14-20, 09:20 AM
PJmax's Avatar
Group Moderator
Join Date: Oct 2012
Location: Northern NJ - USA
Posts: 61,828
Received 1,473 Votes on 1,361 Posts
That's the wiring outside at the condenser. We need to see the wiring at the air handler.
 
  #3  
Old 12-14-20, 10:24 AM
P
Member
Thread Starter
Join Date: Feb 2014
Location: United States
Posts: 27
Received 0 Votes on 0 Posts
So I went into the attic just now to look at the wiring up there in the handler unit.

I assume one of the wire looms goes to the thermostat, and the other to the board on the condenser unit then they meet up in the attic to pair up with the blower motor?

Red's pair up -- 3 wires total (one other thicker red wire)
Blue's pair up -- 2 wires total (no other wires)
Orange pair up -- 2 wires total (no other wires)
Yellow pair up. -- 2 wires total (no other wires)
Brown pair up. -- 4 wires total (two other thicker brown wires)
White pair up. -- 2 wires total (no other wires)

Green are NOT paired up (see box)
ONE thicker white wire is NOT attached to anything (see box)

Sorry I am just not A/C pro here...

 
  #4  
Old 12-14-20, 10:39 AM
PJmax's Avatar
Group Moderator
Join Date: Oct 2012
Location: Northern NJ - USA
Posts: 61,828
Received 1,473 Votes on 1,361 Posts
Thermostat -------------- air handler ----------- defrost board
--- red(R) ------------------- red ---------------------- red(R)
-- brown(C) ---------------- brown ----------------- brown(C)
- orange(O/B) ------------ orange ---------------- orange(O)
-- yellow(Y) ---------------- yellow ----------------- yellow (Y)
-- green(G) ---------------- green
------------------------------------------------------------ green(W)

I know the green wire from the thermostat goes to blower control at the air handler.
What does the green wire coming from the defrost board connect to ?
A picture would be ok too.
Do you know if you have electric reheat coils ?
 
  #5  
Old 12-14-20, 01:22 PM
P
Member
Thread Starter
Join Date: Feb 2014
Location: United States
Posts: 27
Received 0 Votes on 0 Posts
Thanks PJ -Sorry if I misunderstand-
The green wire from the control board at the condenser unit outside doesn't seem to go to anything. I believe the green wire I marked out above is the other end of that. So I should be safe to hook that unconnected green wire into the wire nut with the green & dark green wires?

If you mean what does the dark green wire go to I've attached photos (relay up top?) The thicker blue wire goes to the blower motor, so this looks like its all blower motor related.

No on reheat coils - this looks like a standard heatpump. Just runs in reverse for heat. Just have a regular evaporator coil in the blower assembly thats it.



That lone white wire goes to a (relay?) at the bottom but nothing is attached to it either.

 
  #6  
Old 12-14-20, 05:29 PM
PJmax's Avatar
Group Moderator
Join Date: Oct 2012
Location: Northern NJ - USA
Posts: 61,828
Received 1,473 Votes on 1,361 Posts
You have/had electric reheat. That white wire capped off is going to a sequencer relay. That relay controls the heating element and the blower. The green wire coming back from the defrost board would have powered that white wire and the reheat. If you look above that sequencer..... you'll see #20. That white piece where the black wire connects is the end of the heating coil. It may have gone bad and have been disconnected.

It's not critical to have. One plus is when the system defrosts.... the electric keeps the inside air from getting ice cold. It's also used to aid in heat recovery if the heat pump can't keep up.

So that brings us to why no heat. It looks like the heat pump wiring is correct. Have you gone in to the stat programming and checked to make sure it's correctly set to heat pump.

Press MENU:
Outdoor equipment configuration needs to be set to HP1 (heat pump)
Indoor equipment configuration needs to be set to EL1 (single stage)
 
  #7  
Old 12-14-20, 07:34 PM
P
Member
Thread Starter
Join Date: Feb 2014
Location: United States
Posts: 27
Received 0 Votes on 0 Posts
Well I feel silly I think its working now after I changed the outdoor to heat pump - it was set on conventional cooling 1.

I know before all this mess, I didn't have the c-wire at all...so maybe it never worked until I got the c-wire properly wired in, and now I've set it to heat pump its working!

My 2nd A/C unit had the same issue but I'll get the c-wire into that one and hopefully it'll work the same as well and problem solved! Thank you so much for the help!!
 
  #8  
Old 12-14-20, 08:40 PM
PJmax's Avatar
Group Moderator
Join Date: Oct 2012
Location: Northern NJ - USA
Posts: 61,828
Received 1,473 Votes on 1,361 Posts
It wasn't the C wire.

The stat comes programmed for a standard system. That would be a gas furnace with split A/C.
The A/C worked but the heat didn't because it was trying to activate a furnace instead of the condenser.
 
 

Thread Tools
Search this Thread
 
Ask a Question
Question Title:
Description:
Your question will be posted in: