Upgrade to Y plan with room stat, cables required?
 

I have a thorn olyimpic boiler in the kitchen and a storage tank upstairs in the airing cupboard. I have no controls in the system except mechanical danfoss timer.

my plans are as follows:-

1. fit new worcester bosch greenstar 24ri condensing boiler
2. fit 3 way valve at the T joint straight after pump.
3. fit honeywell wireless controls ( cm zone equipment hc60ng,cm67z, tank stat and 6 x hr80 trv valves to rads )

My questions are :-

1. anybody using this new cm zone equipment? comments please.
2. What cables will i have to run from my airing cupboard to my boiler ( i only seem to have one cable feeding pump)and what type of cable will i require?
3. if i fit a "wiring center" in the airing cupboard, does it have to have a seperate supply other than that to the boiler?


The new boiler is to be installed by local company .

any comments/tips greatly appreciated

Daz

Upgrade to Y plan with room stat, cables required?
 

In an earlier contribution to this discussion,
dbroms wrote:

I have a thorn olyimpic boiler in the kitchen and a storage tank
upstairs in the airing cupboard. I have no controls in the system
except mechanical danfoss timer.

my plans are as follows:-

1. fit new worcester bosch greenstar 24ri condensing boiler
2. fit 3 way valve at the T joint straight after pump.
3. fit honeywell wireless controls ( cm zone equipment hc60ng,cm67z,
tank stat and 6 x hr80 trv valves to rads )

My questions are :-

1. anybody using this new cm zone equipment? comments please.

Can't comment on this - no exerience - but I imagine its alright. I'm using
a CM67 (non RF) room stat which works ok. The latest RF stuff works at a
different frequency from the earlier version, dedicated to intermittent
operations - so hopefully won't interfere with anything else.

There's no point in having a wireless cylinder stat if all your wires
congregate in the airing cupboard.

2. What cables will i have to run from my airing cupboard to my boiler
( i only seem to have one cable feeding pump)and what type of cable
will i require?
3. if i fit a "wiring center" in the airing cupboard, does it have to
have a seperate supply other than that to the boiler?

The basic Y-Plan wiring is shown in
http://content.honeywell.com/uk/homes/systems.htm
One modification which you will almost certainly need is to provide for pump
over-run. So the boiler needs a permanent live in addition to the switched
live shown in the diagram, and the pump needs to be connected to the
boiler's 'pump' terminals rather than wired in parallel with switched live.

The diagram assumes that the whole system - including the boiler - is fed
via the wiring centre from a dedicated FCU. If it's more convenient to power
the boiler from an FCU - and then bring the mains connections up to the
wiring centre from the boiler rather than down to the boiler from the wiring
centre, it will work perfectly happily. To answer your specific question,
the whole system must be powered from the *same* supply rather than separate
supplies - so that the whole lot can be isolated by a single switch throw.
[I rewired my system to be powered from the boiler end via a 13A plug to
make it easier to connect to a generator in the event of a power cut]

The wires you need between wiring centre and boiler will be:
* permanent line
* neutral
* earth
* switched live
* pump feed

So you can do everything with one 5-core cable.

Presumably the existing programmer and the switching unit for the RF room
stat will both be in or very near to the airing cupboard - so connecting
those to the wiring centre will be easy. You can probably continue to use
the existing timer as long as it:
* provides independent CH and HW control (you may have to remove a link to
achieve this)
* has a HW off connection (note that the cyl stat also needs to be a
change-over type with 3 connections)
- and as long as you don't want any fancy timing programmes for the HW

So you set the existing timer for when you want HW on, and set HW to timed.
You then set CH to constant - and use the programmable feature of the RF
room stat to do the *actual* timing.

HTH.
--
Cheers,
Set Square
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Please reply to newsgroup. Reply address is invalid.

Many thanks set square for the excellent advice. I will be using my supply from my boiler upto my wiring center as advised


once again Thanks

Daz