Wiring UFH system help

[alexm1992]

Hi guys,

I have a set up with rads upstairs and UFH downstairs. I have installed the manifold for the UFH along with 2x Honeywell 2port values, one near the manifold and the other on the radiator side. I will be using Nest 3rd gen thermostats to control both the upstairs radiators and downstairs UFH zones - 1 thermostat upstairs and 3 thermostats downstairs.

I am just getting my head around the wiring for the complete system and have put together a quick diagram to show where im at with things. Note that I have not yet shown the wiring of the actuators and heatlinks (for the nests) into the UFH wiring center (Danfoss FH-WC). Before I proceed with this I would like to check with you kind folks that what I am proposing so far wiring wise makes sense?

There are 4 questions/points on the attachment that I am unsure about, and of course if there is anything else which is wrong it would be great to know.

Thank you very much for any help provided

Parts/materials:

Danfoss FH-WC wiring center
Honeywell Home 2 port valve
Nest 3rd gen thermostat
Worcester 36CDI combi boiler

Alex

 

[fowlerboi]

Good idea with the 5 core.

You need to have a 3 pole isolator for the UFH because that orange wire will be live in certain situations while the isolator is off and it would be dangerous for anyone working on it to assume its all isolated.

Are you hard wiring the nests or having them on a stand and charging via usb? If you're hard wiring you'll need to allow provisions for those cables too. T1 T2 on the heat link.

Other than that it looks good to go, I'm no electrician though so take that with a pinch of salt.

 

[alexm1992]

Good idea with the 5 core.

You need to have a 3 pole isolator for the UFH because that orange wire will be live in certain situations while the isolator is off and it would be dangerous for anyone working on it to assume its all isolated.

Are you hard wiring the nests or having them on a stand and charging via usb? If you're hard wiring you'll need to allow provisions for those cables too. T1 T2 on the heat link.

Other than that it looks good to go, I'm no electrician though so take that with a pinch of salt.

I think you meant a 4 core isolator, but you are definitely correct with this all 4 cables need isolating!

I will have 2 nests which can be easily hardwired. I will allocate a cable to power these and the other two will be on stands.

Many thanks will send a photo when it's done!