Wireless Update Question

[plumbinguser]

Hi

I currently have two central heating zone valves (downstairs and upstairs) and how watrer zone valve. These are connected to a Horstmann 3 zone timer. The room thermostats are simple wireless units just temperature based.

I wish to change the thermostats to be ones that have time and date on them and can accept multiple temperatures at different times of date (I find I am keeping the timer on all day and manually adjusting the temperature at night time to keep it low ~ 16 degrees C and putting it up to 19 downstairs during these cold days).

The new thermostats also need to be wireless but I can not find (from the manufacturers data) ones that allow two zones (I presume that these exist). I will keep the existing timer as well, setting it for continuously on on the zones, hot water still timed - this way in summer I can simply use that to globally turn off the heating without reprogramming the wireless)

I would appreciate any advice on a good, reliable wireless system that can control the two radiator zones.

Many Thanks.

 

[WHPES]

The Honeywell CM927 remote thermostat can be used to control up to 4 zones

Honeywell CM927 7 Day Wireless Programmable Room Thermostat [CMT927A1049] - £103.60 : UK Plumbing, Online Shop

 

[plumbinguser]

Thanks for the reply.

Had a quick look and it does support up to 4 zones (I presume there are links to change the frequency). There are a lot of installer options but as a user can I just use the defaults when using for two CH zones ir is there some method of each knowing about the other and optimisation seetings?

 

[Puddle]

As you have a 4 zone programmer already,cost wise it would be about the same just to replace your two existing wireless units you already have with two seperate new units with programable temp changes
most come ,to operate on two availibe seperate frequencies, as standard,ie you can use one for each and this probably will also give you more optoions to pick a model that has the operating system that suits you

 

[doitmyself]

Had a quick look and it does support up to 4 zones (I presume there are links to change the frequency).

These units work in a similar way to car locking systems; the signals are encoded so no two keys have the same code. The same goes for the controller and relay units of the CM927.

There are a lot of installer options but as a user can I just use the defaults when using for two CH zones or is there some method of each knowing about the other and optimisation settings?

Honeywell no longer publish the info about using these for zoning, you have to ask them nicely - and they are a bit picky if you are not in the "trade". But essentially you have to nominate one controller/relay pair as the synchronizer. You also have a third relay to act as the actual boiler control. Each pair controls just the relevant zone valve. The synchronizer turns the boiler on/off as required. The idea is that you don't get one saying "turn it on" when the other is saying "turn it off".

If you can get hold of the instructions for the CM67 (not the CM67z), you will find it all explained there.

There is also the Honeywell CM Zone system, which uses wireless Thermostatic valves, but it is quite expensive. The basic pack (control, relay, 6 TRV heads) is about £500. Extra TRVs heads are about £75.

More info

 

[plumbinguser]

I am now a bit confused.

The current system I have appears to use the thermostats to turn on the zones valves (one each - frequency selectable by a series of links in the unit). The output of the zone valves are basically in parallel along with the valve output from the boiler thermostat side and then go to the boiler. If one is off then it does not affect the others (as they simply close when calling for heat).

Does the Honeywell system work differently using the synchroniser?

I will try to get the CM67 intsructions

Thank you