honeywell cm927 controller and a biasi garda he plus help!

[jimble]

i recently bought the honeywell cm927 controller on the recommendation of a couple of friends. Since i installed it it has never run to the programmed times? All it seems to do is work as a room thermostat and switches the heating on and off according to temp setting.

As far as i can see from the wiring diagram the receiver is wired correctly (heating is coming on and off) - so i presume the issue is with the transmitter (control box)

the wires from the fuse spur go to the block inside the boiler then there is the block for switching wires (this is the one that has the connector in when not using external controller)

wires in the receiver are as follows
live comes from +ve on fuse spur block and goes to l next to n
negative comes from fuse spur block and goes to n
i've jumpered the two L's together
A and B are the 2 wires that go into the control block

if any one has any suggestions to why it only works as a thermostat and not timer they would be greatly received - (yes the controller has been switched to auto!)
i believe the fault lies with the controller and not the wiring (The receiver is receiving a signal and turning the heating on and off as it should do - its just getting the signal when the heating should be off)

Thanks

 

[Whitespirit66]

I think the jumper maybe the fault.

You just need L an N connected to the receiver, and the two switching connectors on the receiver should be connected to 1 and 3 in the boiler.

Try without jumper.

 

[jimble]

i've only recently put the jumper in to see if it made a difference! - but it didn't
thanks for the reply

i cant see a 1 and 3 in the boiler its just the block

but like i said boiler is switching on and off and firing up and providing heat (much to the pleasure of the wife!)

 

[paulthegas]

you have fitted a programmable room stat.........it sound as though it is doing its job, if u dont want the heating on at certain times, lower the temperature for that period!

 

[jimble]

yeh that's that the problem the central heating is coming on when its programmed not to! - set to come on 6-8.30 , 4-10.30
but is on in the middle of the day and in the middle of the night

Have checked by altering clock to a time period that is outside of programmed ones and altered thermostat and it just clicks the heating on and off.

The more i think the more i believe that the programmer unit is faulty
The wiring i now know to be correct as the friend who recommended the unit photographed the wiring on his and it fits the description given by the first reply to this post.

The only other thing is that there is a setting on the programmer that is telling it to behave just as a thermostat and not a programmer - but have scoured the instructions and followed them accurately.

All replies appreciated thanks for your time

 

[mikely]

i recently bought the honeywell cm927 controller on the recommendation of a couple of friends. Since i installed it it has never run to the programmed times? All it seems to do is work as a room thermostat and switches the heating on and off according to temp setting.

Have you set the mode switch to AUTO?

As has been pointed out, a programmable thermostat does not turn your heating on and off like a programmer, it varies the temperature through the day. So if you want the heating off during the night, set the temperature, for example, to 12C at 10:30pm and then 18C at 6am.

 

[Agile]

i believe the fault lies with the controller and not the wiring (The receiver is receiving a signal and turning the heating on and off as it should do - its just getting the signal when the heating should be off)

Thanks

The fault lies with Jimble !

He does not understand how a programmable stat works.

He has been told above but does not want to understand!

All it does is to set the TEMPERATURE from a particular time.

For example at 2330 when you go to bed it sets the temperature to say 10 C overnight and at 0730 it raises it to say 21 C.

Tony

 

[jimble]

Thank you for your replies and now that it has been explained the fault does lie with me.
My experiences of central heating timers is that they have an on and off settings.
I will programme the thermostat with a lower temperature for overnight - the last one been 10.30 will set it to 16.

Thank you for your replies it has helped clear up the problem - now i know how a programmable thermostat works and this forum has helped!