New Drayton RF601 Thermostat Too Sensitive?

M271

On Friday I had a replacement Drayton RF601 Themostat and Receiver Unit fitted after an issue with my previous RF601 that had done 11 years of serving me well.
I have found that the new Thermostat calls for heat very frequently when at the set temperature and operates within a very small temperature window. What I mean is that the flame symbol appears on the Thermostat which switches the boiler, pump etc on, then 3 or 4 minutes later it switches off then 3 or 4 minutes later back on again and again. With no apparent change in temperature (less then 0.1 degree) which I have measured with another digital thermometer adjacent to the Thermostat (the thermometer measures to 0.1 degrees).
My old RF601 Thermostat didn't call for heat so frequently and seemed to operate within a 0.5 degree window or so, so yes the temperture in the house did fluctuate a bit but then the heating came on for longer periods.
I have read that it is not good for the system components (boiler ignition for example) for the heating to come on and off so frequently and that digital Thermostats normally operate at between 0.5 to 1 degrees i.e. if set at 19 may switch off at 19.25 and back on at 18.75 for example.


Maybe the new Thermostat is working as it should but being so sensitive and calling for heat within such as small temperature window doesn't seem right to me.


Has anyone else had this issue or if this is just the norm with modern Thermostats?

coffeehound

It is usually user selectable — the manual will tell you how to change it.

M271

I can't see anything in the instructions which allows me to adjust the sensitivity. Only one setting if it is Gas or Oil boiler and another if the house normally heats up in under or over an hour.

getmore4less

Stick your old thermost back the most likely cause of your fault was the receiver.

molerat

I wonder if it is a function of the system capability setting ?

notbritishgas

I had a Drayton Digistat 2 RF that went faulty, not knowing if it was the thermostat or receiver faulty I bought both of them.
When fitting them I found they were working just as you describe, 3-4 mins on then 3-4 mins off.
As it was the receiver faulty I put the old thermostat back.

But thinking about it my wife always complains when the room heats up and switches off, the radiators cool and the room seems colder until later on the heating comes on again.
Perhaps the new thermostat once the temperature was reached would keep the radiators warm all the time.
Now whether that would use more gas I do not know, but just in case that is why I put the old thermostat back.
What do other people think.

M271

getmore4less wrote: »

Stick your old thermost back the most likely cause of your fault was the receiver.

Yes I was thinking about that as it was a receiver problem.
I'll email Drayton and get their take on it, maybe its a faulty Thermostat or they may confirm that this is what it is supposed to operate like. Maybe modern heating control devices have to be more accurate for energy efficiency?

M271

molerat wrote: »

I wonder if it is a function of the system capability setting ?

It maybe, I was wondering that.



I'm emailing Drayton anyway so they may be able to confirm that.

getmore4less

Forgot the obvious question you have shutdown the old thermostat.

M271

notbritishgas wrote: »

I had a Drayton Digistat 2 RF that went faulty, not knowing if it was the thermostat or receiver faulty I bought both of them.
When fitting them I found they were working just as you describe, 3-4 mins on then 3-4 mins off.
As it was the receiver faulty I put the old thermostat back.

But thinking about it my wife always complains when the room heats up and switches off, the radiators cool and the room seems colder until later on the heating comes on again.
Perhaps the new thermostat once the temperature was reached would keep the radiators warm all the time.
Now whether that would use more gas I do not know, but just in case that is why I put the old thermostat back.
What do other people think.

Interesting to hear from you the similarity of our experiences including the radiator temperatures. Maybe the temperature operating window for switching the heating on and off is tighter on the newest controls but my experience is that it is too sensitive (less than 0.1 degree)

It just doesn't seem right to me that the heating is firing up that frequently, my receiver unit won't last 11 years like the last one at this rate, let alone the other system components.
Did you have to re-pair your old thermostat to the new receiver or did it just recognise it?

M271

getmore4less wrote: »

Forgot the obvious question you have shutdown the old thermostat.

Yes I took the batteries out to make sure.