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 HVAC Guru Your Own Question
HVAC Guru
HVAC Guru, HVAC TECH
Category: HVAC
Satisfied Customers: 14620
Experience:  15yrs in the HVAC industry with certificates and degrees.
21107370
Type Your HVAC Question Here...
HVAC Guru is online now
A new question is answered every 9 seconds

Replacing a Honeywell ST9160B Controller with a HQ1012358HW

Customer Question

Replacing a Honeywell ST9160B Controller with a HQ1012358HW and can't figure out where the M1 and M2 connect to since it isn't labeled the same.
Submitted: 1 year ago.
Category: HVAC
Expert:  HVAC Guru replied 1 year ago.

Hello and thanks for using this service, if you have been waiting do not worry or get upset I am just one of the techs on here and I try to get to as many customers as I can and I just picked up your question now. Please give me time to respond as typing, researching and adding links takes me time to do so please be patient and often I will ask you questions to narrow down the issue to get is diagnosed correctly.

Was there a reason you did not get a drop in replacement?

Expert:  BillyHvac replied 1 year ago.

The M1 and M2 are parking spots for unused blower wires. They may say PARK...but basically they are dummy terminals just to put unused blower wires on

Expert:  BillyHvac replied 1 year ago.

so you will have a wire for heat blower and cool blower...any speeds leftover and not used are just put on m1. m2, park etc for convenience to store

Customer: replied 1 year ago.
The M1 and M2 are on the Old Controller, where do I put them on the New Controller?
Customer: replied 1 year ago.
I Googled the Part Number on the Old Controller which was HQ1012358HW and this is what I ended up with.
Expert:  BillyHvac replied 1 year ago.

the boards are interchngeable and both will show when googling.

By your HEAT, COOL Terminals do you have terminals labeled park? and the new controller is the 9160 or the HQ?

Expert:  HVAC Guru replied 1 year ago.

I am sorry another person has kind of jumped in here and they do not appear to have the correct answer for you, if you would like to continue with me just let me know HVAC GURU instead of Billy to get the correct answer instead of wasting time.

Expert:  HVAC Guru replied 1 year ago.

I originally responded to you but often some of the techs on here confuse things for the customers, if you want to deal with him or me just let me know

Expert:  BillyHvac replied 1 year ago.

The terminals are labeled as unused

Expert:  BillyHvac replied 1 year ago.

M1 and M2...Unused...Park....are all the same....so use UNUSED, M1, M2 as the same

Expert:  HVAC Guru replied 1 year ago.

You should ask Billy for a diagram of this to show you as often he jumps in and it is incorrect.

Customer: replied 1 year ago.
HVAC GURU - Where do M1 and M2 connect to?
Customer: replied 1 year ago.
Billy: Can you give me a Diagram of this?
Expert:  HVAC Guru replied 1 year ago.

I am sorry he has locked me out of the question for awhile, since he seems to have mucked this all up I will let him respond to you, if he does not get you anywhere I will post back...I am sorry for this trouble.

Expert:  BillyHvac replied 1 year ago.

Thank you for waiting while locked.

On page 3 HERE

it tells what terminals cross over to others.

Wires that were on UNUSED go on M1 and M2

Wires that were on M1 and M2 go to UNUSED

I also have the diagram for your furnace if your concerned with other wires

Expert:  BillyHvac replied 1 year ago.

Black wire is commonly on COOL

Red wire is commonly on HEAT

Other color wires like yellow, blue, orange...go on M1 and M2 or unused

White goes to neutral

Expert:  HVAC Guru replied 1 year ago.

If you are still not sure about the issue you can always request a refund as this may not have been the best experience for you on the site, my apologies again.