A mate has one of these and wants to fit a RF Room Thermostat. He can't find the manual - are there any tricks or traps?
Is it easy to pick up a live, neutral and switched feed? Is there a connector strip or similar?
Also any views on a good RF Stat?
Yup, all fairly straightforward.
The Honeywell CM927 7-day RF progstat isn't the cheapest but in my experience is reliable and easy to program and use. My target price is £79 ex VAT, £93 including. There's a cheaper 1-day version you can get from Screwfix.
Just read the spec - question - if it is a 2 wire connection then how is the boiler receiver unit powered as I guess it doesn't have a neutral. Does it just operate in series with the boiler electrics - picking up current in the same way that a PIR light switch does?
On the Potterton is there an easy to access link / bridge to remove in order to fit the unit?
I cannot help you with the Potterton wiring diagram (I do not have one), you will have to take peek at it yourself.
I can recommend Drayton RF stats and suggest that you stay away from Siemens and Salus.
The Siemens have a fantastic failure rate and Salus have the worst support team in the world.
I fitted 100 Siemens RF stats/RF programmers last year and 20% failed in one way or another. I also fitted 20 Salus RF stats/programmers and had one failure (faulty when new) but the company never calls you back when you leave a message or six.
I also fitted about 30 Drayton RF stats/programmers. Not one failure.
Adam
To fit:
I presume this installation has zone valve? and works both heating and HW?
If so the wireless stat must be wired into the control wiring. The receivrs power will come from there and the receiver contacts will be in series with the supply to the heating zone valve motor.
If by some chance this is a heatign only installation then...
There is a connection block on the lower front right of the drop down section of the boiler.
The four connections on the right of this connection block are
PL, N , E and SL . (not sure which order).
PL and N supply permanent power to the receiver and the receiver contacts are in series with the wire to SL to make the boiler run.
HTH
Yes it needs live and neutral from the system controls (after the 3A fuse and isolating switch feeding the rest of the system.
Does
No
Off the top of my head, the Potterton has a mains (L+N) feed from the system fuse + switch, and a switched live terminal from the controls system to tell it when to fire up. You'd wire it as per a standard Y-plan or S-plan system (whichever you've got) with the progstat taking the place of both the CH side of the programmer and the CH wall stat. What have you/your friend got at the moment?
I haven't looked - but he has no room stat. So I presume the receiver will go in place of the CH feed to the timer.
If it is two wire then if it was on the live and neutral how does it switch?
It's not 2-wire. At least, not the ones I've used.
Yes if it's a programmable thermostat since that'll take care of the timing as well as the temperature control. Would he keep the programmer to control the hot water?
Sorry - I feel sure I saw one which claimed to be 2 wire. Seems unlikely
From web page:
The CM700 range of programmable room thermostats is designed for social housing provider and specifier market needs by providing automatic time and temperature control of domestic heating premises. Large LCD display with simple to program and easy to use functionality. No installer links or switches on the back of the unit means no adjustment is required for combi boilers and most central heating systems. The CM700 range has a scheduled maintenance alert, fault diagnostic mode and automatic Summer/Winter time change to assist in maintenance. The range caters for all requirements with hard-wired or wireless versions and 1 day or 7 day programming. Two wire, volt free connections are ideal for use with combination boilers. A simple user guide is now available in the Download Centre under 'Quick Install'. Features:
He has spotted a Drayton TLX RFP and is going to order it.
He has a digital programmer - I need to give some thought to the wiring - I am guessing there will be a link for the room thermostat on the boiler connections.. Any thoughts?
I have downloaded a wiring diagram - same for 30e to 100e..
Blowed if it is as obvious as I expected. Off for a pint.
Hope someone can offer to take a look
In message , ARWadsworth writes
I'm bound sure to have a profile interconnection diagram somewhere
Should that be Sunvic not Drayton?
Adam
There used to be a torrent of many manuals floating about. I cannot find it now.
Adam
I have found it.
Adam
If you want that full manual email me.
Adam
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