Q: If I replace a Honeywell 921B receiver with a Siemens REV24-RF 7-Day Wireless Programmable Thermostat unit, is the wall plate for new receiver the same or do I need a wall plate?
If I need a new wall plate what is the model number?
A: You will need to replace the wallplate, a new one comes with the REV24-RF.
Q: Currently have Honeywell 921B wireless room stat and receiver.
Room stat has started to develop a problem in that the digits are not displaying properly.
Have read in various forums and sites that the problem described above is common to Honeywell, my unit is about 4 years old. Have wrote to Honeywell and as expected no response.
Will the Honeywell CMT927 (CM927) Wireless Programmable Room Thermostat be suitable as a replacement and will I be able to use it with the existing receiver I have or will I have to replace the receiver?
To ensure I don’t have to replace the unit in say 4 years or so with the same fault developing would I be better off with the, Siemens REV24-RF 7-Day Wireless Programmable Thermostat.
Is the Siemens better value for money and more reliable?
Is the wiring the same in terms of number wires that the Honeywell 921B uses?
Will I just be able to take off the existing receiver and put this one in its place?
Do you recommend any other make?
A: The CM927 will connect to your existing receiver fine.
Replacing with another make such as the Siemens REV24-RF would be what I would recommend currently, although it would mean changing the receiver. The Siemens receiver will connect to the same 4 wires.
Q: Hi, I have a Honeywell Smartfit y system fitted, can you recommend a wireless controller that will work with this please.
The controller is currently hard wired, 2 wires to the base box.
A: Unfortunately there is no wireless controller that will work with the Smartfit system. You will need to replace the whole system including motorised valves to have a wireless control.
Q: I already have the controller for CM927 but need a new receiver, can I buy one of these separately or do I need to buy the whole thing again??
A: Yes you can buy the receiver. HCO Code 09A03
Q: Will the CM927 operate more than one zone valve for heating purposes? There seem to be a lot of reports of failures is this still the case and would I be better with another model/make?
A: Yes, you can wire two zones valves in parallel to the receiver, or order a second receiver and have it control both receivers.
We are not currently recommending the CM927 due to quality issues. I would consider the Danfoss Randall TP7000-RF instead.
CMT927: 7 Day Wireless programmable thermostat (Allowing temperature programmes to vary for each day of the week)
Replaces obsolete CM67-RF-NG (CM67NG) model Y6667D1086
* Also known as CM927
* Complete with receiver
* Pre-bound so no initial binding is required on site.
* Can be used for heating or cooling.
* Up to 6 programmed temperature changes per day
* Extra large display
* Automatic Summer/Winter time change
* Holiday function
Allows you to set a constant temperature (default = 10C) for a specified number of days (from 1-99 days). This lets you save energy and related costs when you are away from home but resumes normal operation the day of your return.
* Party function
Allows you to extend your heating program by a specified number of hours at a particular temperature before resuming with the normal temperature program. This function can also be used to reduce the temperature when you leave the house for a short period
* Day off function
Allows you to temporarily run Sundays heating program for as many days as you desire
* Built in Optimum Start feature (can be disabled)
Ensures that the optimum temperature conditions are achieved at the required times. This is an energy efficiency feature that adjusts the start time of your heating system depending on how cold it is.