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 Plumberpro Your Own Question
Plumberpro
Plumberpro, Plumber
Category: Plumbing
Satisfied Customers: 634
Experience:  Heating and plumbing answers. 20 years experience
77408428
Type Your Plumbing Question Here...
Plumberpro is online now

Connecting Nest to Honeywell programmer

Customer Question

How to connect Nest Heat Link  to Honeywell ST9400C1000  programmer

Submitted: 2 years ago.
Category: Plumbing
Expert:  Plumberpro replied 2 years ago.
Customer: Hi .do you have an existing room thermostat?
Customer :

yes

Customer :

hi

Customer:

Ok , so you have the heat link and the nest thermostat?

Customer :

Yes, 4 cables connected to heat link, neutral, live and 2 others

Customer:

Ok . they will be 240 volt from the programmer and back to switch the boiler on . there should be two connections( t1 and t2 that goes to the nest thermostat. These at 12 volt

Customer:

Does that make sense to you?

Customer :

yep, ive connected other 2 to port 2 and 3

Customer :

Full Size Image

Customer:

Ok , so the programmer, heating on routes through the room stat , to the motorised valve and on to the boiler

Customer :

can you check the pic?

Customer:

I think all you need to do now is connect t1 and t2 to the nest

Customer :

you see i dont want to use old thermostat placement

Customer:

That's ok .was a lead supplied to connectvtge heat link to the nest?

Customer :

before i have use it in the previous house and different boiler so i have attached lead.

Customer :

in the new house i have differrent boiler

Customer :

so i know where to connect live cable and neutral. but im not sure what about the rest

Customer:

Ok , but you have managed to wire up the heat link apart from the he room stat

Expert:  Plumberpro replied 2 years ago.
Our chat has ended, but you can still continue to ask me questions here until you are satisfied with your answer. Come back to this page to view our conversation and any other new information.

What happens now?

If you haven’t already done so, please rate your answer above. Or, you can reply to me using the box below.
Plumberpro and other Plumbing Specialists are ready to help you
Expert:  Plumberpro replied 2 years ago.

Out of programmer 4 to 2 of heat link.out of 3 of heat link into motorised valve .any probs , give me a call