Wiring a second zone to combi boiler,

[foxy1609]

Hi,

My first post, well what's to come?

Need you guys help please.

Client want a second zone adding to a glow worm combi, plumber has fitted both 2 port honeywell valves and a heatmiser stat for the UFH

What weve got,

Honeywell CM901stat controlling existing radiators in bungalow
Glow worm Combi CXI30
Heatmiser Setback programmable stat
2 x honeywell 2 port valves
Additional pump pack for UFH

Advice on wiring this lot up would be greatly welcomed.

Best,

Martin

 

[bigspark17]

Just to clarify your requirements...
Zone 1- existing rads
Zone 2- new UHF system

What programmer currently operates the heating.?
howmany zones are on the UHF.?

 

[foxy1609]

Hi bigspark

Z1 Existing rads on CM901
Z2 New UFH on heatmiser,

only the one additional zone, its just for one room extension.

Best, M

 

[bigspark17]

Not fairmiliar with gloworm.. Does the system currently have a wiring centre or do you have the cm901 flexed into the boiler via flex outlet locally (as I suspect) into the LS -LR connections.?

 

[electric will]

Is it glow worm that have that weird module set up, where it needs a mother control unit to operate 3 port valve etc, it communicates via a low voltage can bus system? I'm sure it was one of these I got caught out on once. Sorted it out ok but couldn't do it the conventional way.

 

[foxy1609]

Hi
Yes your correct, just an external room stat, that's existing, just need to add this extra zone.
Cheers

 

[foxy1609]

Hi will
I know there's just connections on it for external room stat.

Best,

 

[bigspark17]

youll need to include a W/C(wiring centre) now in your dedign, the cm901 roomstat will need to be routed to the W/C along with the 2x 2port valves a suitable cable to the ufh manifold box a twin channel programmer will need to be included, 1-ufh, 2-rads , you will need to wire the set back stat to the manifoldbox and the additional pump will connect to the maniflod box also ( if it is purely for the ufh) , obviously a return leg to the boiler to operate the boiler from the orange return of the valve. also ull need to check the supplemantary bonding with new pipework. buy a decent W/C and youll get a wiring connection illustation on the inside cover. froststat you could suggest to customer.?


personally the customer may have been better opting for an electric ufh system as it was 1 room.. but thats beside the point i know .. plumbers not explaining how much electrical work involved with the adding one zone.!