Recent: Safely remove screen protector from a Macbook Air?

Mend > Home Heating Systems

Mend Honeywell CM921 Box Working Fine

How can i marry my honeywell CM921 the the BDR91 relay box?

we have a Honeywell CM921 thermostat and a BDR91 relay box, for the past two years was working fine. However recently the system appears to have stopped recognising eachother. To make the heating work we have to override the system we have to press the green button however the red button continues to flash. Any suggestions or tips would be most welcome.

David
January 2011
HoneywellHoneywell CM921Heating, Home Heating SystemsBox Working Fine
does it have batteries?

brian
January 2011

Automatic Answer

We may have found other answers which could help you.

Click here for Box Working Fine

Related Questions ...

Mend thermostat boiler Worcester Bosch
1

problem with boiler after replacing batteries in thermostat?

i changed batteries in boss thermostat and discovered that the boiler wasnt responding to thermostat, even tho... [Read more]
Mend boiler heating thermostat
1

Glow-worm Space Saver 50-60F?

When the boiler fires up, there a buzzing/vibrating sound. It seems to be coming from the metal box on the bot... [Read more]
Mend heating thermostat controller
1

Whistling noise and blank screen on my potterton 2001!?

I have a potterton ep2001 controller on my gas heating system.It was working fine when i switched it off but w... [Read more]
Mend water problem going
3

No water in hot water tank?

Hi there, I have a problem... lol I'm afraid I'm going to err on the side of giving too much information... [Read more]
Mend combi boiler central heating lockout
3

Vaillant GB2 EH - Got DHW but no CH and its freezin!?

Hi Guys - am in desperate need for tips on how to fix our Vaillant VCW-GB-282 EH Combi. Installed about Apr 19... [Read more]
Mend boiler heating radiators
3

How can I fix the heating on my Baxi Combi Instant 105e?

I have a Baxi Combi 105e. The hot water and heating is on but the heating is not working. When I turn the temp... [Read more]
Mend potterton hot water
2

No power to mu potterton control panel?

Up until yesterday my system was working ok, with the hot water starting every day. I tesed the CH on Wednesda... [Read more]
Mend boiler heating pcb
10

Baxi Solo 50/4 Wall Mounted PF Burner Shutdown Problem?

My Baxi Solo 50/4 Wall Mounted PF gas fired central heating boiler ignites when the thermostat calls for heat,... [Read more]
Mend heating boiler control timer
4

How can I fix my Horstmann Economy 7 Quartz/Maxistore boiler?

My boiler sporadically stopped working last week, so I checked the main fuse - it had blown out so i then repl... [Read more]
Mend thermostat boiler home heating

How do I reprogram my ideal bolier rf thermostat receiver?
Mend boiler programmer heating

Fan running continuously?
Mend heating thermostat battery

how often do we change the3032 battery in a digistat +2rf?
Mend thermostat wireless replacement

Replace a wireless termostat with a hard wired one?
Mend thermostat heating repair

Honeywell921?
Mend heating system battery

boss therm not working ?
Mend honeywell temperature heating

is there a way to just simply turn the temperature up?
Mend heating heating timer repair

can i fix it honeywell st1000 ?
Mend thermostat heating replacement

Can you get just a new RDJ10RF thermostat or does it have to be the set?
Mend Heating, Home Heating Systems

Tybox827reset?
Mend remote timer work

Remote timer bps242rf how does it work ??? ?
Mend thermostat wireless receiver

How to remove the front cover of my Digistat 2RF receiver?

How to mend ...

Find out how to mend just about anything howtomendit.com for free repair help, information and advice.
Mend Home Heating Systems ...

Other models...

Honeywell DigistatHoneywell RDJ10RFHoneywell RF1Honeywell RF2

Related Categories

Mend Convector Heaters
Convector Heaters
Mend Fan Heaters
Fan Heaters
Mend Oil Filled Radiators
Oil Filled Radiators

Topic

Honeywell CM921 & BDR91 Pairing - Help!