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BillyHvac
BillyHvac, Journeyman HVAC Tech
Category: HVAC
Satisfied Customers: 22541
Experience:  Endorsed for unlimited heating, cooling, oil burners, boilers, refrigeration, hydronics
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Trying to hookup a Honeywell RTH3100C thermostat, not sure.

Customer Question

Trying to hookup a Honeywell RTH3100C thermostat
JA: Just to clarify, do you think this is a larger HVAC problem, or something specific to the thermostat?
Customer: not sure.
JA: Do you plan on doing the work yourself?
Customer: yesw
JA: Anything else we should know to help you best?
Customer: Don't think so
Submitted: 7 months ago.
Category: HVAC
Expert:  BillyHvac replied 7 months ago.

hello,

Do you have certain wires you have a question on?

Customer: replied 7 months ago.
I don't want to join anything that I have to cancel later. just wanted wiring help. so forget it and cancel it
Expert:  BillyHvac replied 7 months ago.

that is a computer generated offer...not from me..I cannot call anyway.

If you want help with the wiring let me know or I will just send to customer service to cancel

Billy

Customer: replied 7 months ago.
Wiring a Honeywell RTH3100 thermostat with 6 wires from the wall. Yellow, white, orange, red, green, blue
Expert:  BillyHvac replied 7 months ago.

And do you have a heat pump?

Customer: replied 7 months ago.
Expert:  BillyHvac replied 7 months ago.

red to R

yellow to Y

white to aux

orange to O (unless outdoor is Rheem/Ruud product..if so then orange to B)

green to g

blue to c

What brand is outdoor?

Expert:  BillyHvac replied 7 months ago.

also you need a short wire to connect E terminal to Aux terminal

Customer: replied 7 months ago.
It is a Rudd
Expert:  BillyHvac replied 7 months ago.

ok this changes things..

they could have used the blue for B...or the orange for B.

Can you open the air handler?

Customer: replied 7 months ago.
Ok, manual said nothing about the crossover. Thanks
Expert:  BillyHvac replied 7 months ago.

The jumper gets missed alot.

If the O/B is an issue let me know. Rheem and Ruud are the only ones who use B as a reverse valve instead of O.

Billy

Customer: replied 7 months ago.
Where does the orange go?
Expert:  BillyHvac replied 7 months ago.

That is why it is best to open the air handler and see where it goes.

Usually on a Rheem/Ruud the orange is not used....or it is on B....the blue is usually C...but then that Rheem Ruud issue pops up and some techs use blue.

Can you see where the blue or orange attach in the air handler?

Customer: replied 7 months ago.
I don't know where to find the air handler. I'm a dumb ass
Expert:  BillyHvac replied 7 months ago.

do you know where the filter gets changed?

Customer: replied 7 months ago.
No, not on the unit. Is it on the outside unit?
Expert:  BillyHvac replied 7 months ago.

can you tell me the model number of the outdoor unit and I will check

Customer: replied 7 months ago.
UPKA-031JAZ
Expert:  BillyHvac replied 7 months ago.

thank you....leaving that unit are pipes...the pipes lead to a blower unit inside the home...could be attic, closet or basement

Customer: replied 7 months ago.
It's in the attic. What should I look for?
Expert:  BillyHvac replied 7 months ago.

the wires from the thermostat go up to the blower unit in attic. The same wires you see at thermostat then attach to terminals inside the blower. WE just need to see where the orange or blue go.

Do you remember if both attached to old thermostat?

Many times there are extras not used.

Customer: replied 7 months ago.
Old thermos was a Ritetemp 6030.
blue wire to C
orange to B
whiti to white
yellow to yellow
red to rh cross to rc
green to green
Expert:  BillyHvac replied 7 months ago.

Excellent!

Then wire as mentioned...

but red to r

yellow to y

white to aux

orange to B

blue to C

green to G

jumper from E to aux

Thank you!

Customer: replied 7 months ago.
Thank you Billie and Happy New year
Expert:  BillyHvac replied 7 months ago.

you are very welcome and thank you for the patience

Side note...make sure power is off to the air handler when changing the wires..

Customer: replied 7 months ago.
If I have the power off the heater in the main fuse box, is that enough?
Expert:  BillyHvac replied 7 months ago.

I am sorry, I thought we were through. The power must be turned off at electrical panel or the air handler.

Customer: replied 7 months ago.
Well, it didn't work. I'm still without heat. You think it might be a fuse blown?
Expert:  BillyHvac replied 7 months ago.

take the red wire and the green wire at thermostat and hold direct together...does the main blower kick on?

Customer: replied 7 months ago.
Nothing
Expert:  BillyHvac replied 7 months ago.

ok then if the wires were removed from old thermostat while air handler was not turned off it blew a fuse. If we get the model number of the air handler I can direct with pictures

Customer: replied 7 months ago.
Ok, I go to the attic
Expert:  BillyHvac replied 7 months ago.

if you cannot find a number you can post pics of the unit with door off

Customer: replied 7 months ago.
Ubhc-17j11sfd
I can see a breaker on this box and it was not thrown
Expert:  BillyHvac replied 7 months ago.

ok this will depend on the age of the unit if there is a fuse...the fuse I refer to is the the main breaker or fuses..it is a small 24v fuse just for the thermostat wiring.

Looks like we need to open the front....do you know what the transformer is ?

See HERE

Customer: replied 7 months ago.
No I don't. I give up but thanks for all your help. I'll just call someone next week.
Thanks again
Expert:  BillyHvac replied 7 months ago.

I wish you the best...just rate service to move off active list

Billy