Honeywell Programmable Room Thermostat 24 hour CM921

Product Information

Hello, my Honeywell CM921 Thermostat does not display properly, I can hardly see anything on the LCD screen. Year Warranty is available when fitted with an Intergas System Filter and both items are warranty registered with Intergas Heating at the same time.

Honeywell CM900 Wireless Installation Guide - Honeywell

Looking at replacing my CM921 and maybe even the receiver, it’s 10 years old and even with new batteries in the CM921 it seems to be temperamental to touch, in screen sometimes goes blank. Can I buy another same thermostat and bind it with my current receiver, or do I have to change both of them? If you leave it below 1.5m above floor level it may be reading the wrong temperature and causing the boiler to fire up. eg: on a coffee table. Day Off button copies Sunday’s program into any other day of the week, so that you can make the Pro Thermostat follow this program if you have a day or days off. Optimum Start & Stop saves energy and money by getting to the correct temperature at the correct time and turning off the heating early if the room temperature is correct.The Pro Series Programmable Wireless Thermostat replaces the discontinued Honeywell CM927/CMS927/CMS927B1049. This is a 7 day wireless programmable room thermostat designed to control your heating system efficiently, providing comfortable temperatures when you are at home and energy savings when you are away. With wireless communication there is no need to provide a wired connection between the thermostat and boiler. OFF mode has an integral frost protection setting at minimum 5°C (installer adjustable) so that pipes in the house will never freeze in winter It is possible to rebind a new thermostat to your existing reciever. The rebinding procedure will be in the manual. If I set the wireless unit to 18 degrees and the room temp is 21 degrees then surely the heating should stay off when it's in manual mode?

HONEYWELL CM921 PROG R/STAT 24HR RF | Wolseley

Pro Series Wireless Programmable Thermostat | Direct Replacement for Honeywell CM927/CMS927/CMS927B1049 Wireless Programmable Room ThermostatBuilt-in memory holds the user program indefinitely so that it is never lost – even if you remove the batteries The Pro Series Wireless Programmable Thermostat will replace the following Honeywell CM Series products:

Honeywell CM921 | DIYnot Forums Honeywell CM921 | DIYnot Forums

This is a Pro Series Wireless Programmable Thermostat ONLY and does not include a Wireless Relay Box! Not sure what you mean to be honest. The boiler is fixed, the thermostat is wireless and fires the relay to start stop the boiler when thermostat at temperature. That thermostat allows a several time periods throughout the day. If you take a good look at the Pro Series Wireless Programmable Thermostat, you will see it is nearly identical to Honeywell Home’s T3 Series Thermostat (the user display menu is identical). However, the big difference is that the Pro Series Wireless Programmable Thermostat will bind directly to any existing Honeywell Wireless Relay Boxes, where the T3 Series won’t, so you don’t have the hassle of having to get an installer out to fit this. Can be installed standalone* or part of an existing heating system*, including conventional and combi boilers, as well as new heating systems. Wireless connection to the boiler allows you to mount the Chronotherm in your room without disruption

The Pro Series Wireless Programmable Thermostat works with the following Honeywell Wireless Relay Boxes:

Honeywell-Pro CM927 CM921 CM727 CM721 CMS927 Hanicks Honeywell-Pro CM927 CM921 CM727 CM721 CMS927

PF Community Forums General Off-Topic Chat For Sale & Wanted Make a suggestion about the forum in generalThe Honeywell CM921 Wireless 24Hr Programmable Room Thermostat can be used to control the heating circuit in a Sundial S or Y Plan and is particularly well suited to control combination boiler installations or additional zones in a S Plan Plus system. The Honeywell CM921 Wireless 24Hr Programmable Room Thermostat is for use where heating needs are the same from day to day. The CM927 can provide a different heating programme for each day of the week to maximise energy efficiency. Two wire, volt free connections are ideal for use with combination boilers. Honeywell CM921 Wireless 24Hr Programmable Room Thermostat Product Features: Pro Series Wireless Programmable Thermostat – Replaces Honeywell CMS927 & CMS921 Wireless Programmable Room Thermostats I have a Ferolli boiler not even 2 years old with the Honeywell wireless thermostat control unit built on to the thermostat circuit, Also this has gone on for months and months I have given up with my landlord and as I am buying the house anyway I 'd rather spare myself the hassle of speaking with him. The window sensor, isn’t a window sensor as such it’s looking at temperatures changing rapidly due to drafts and the video says it’s hit and miss on open windows so probably wouldn’t use that feature as such.