Digital Roomstat

[johntheo]

Purchase one of these a few days ago, its a FantiniCosmi CH110 stat with no fancy controls, just settable winter and summer settings and settable differential, default setting 0.3C, max 2C.
Problem is that it doesn't switch off at the choosen set point but if you change the SP setting around the actual displayed temperature (which is accurate, checked with digital thermometer) then it switches on/off at the differential setting. It is battery controlled which switches a switched live to the boiler, have changed to new batteries but still same problem.
Has anyone any experience of these stats? or did I just get a faulty unit I wonder.

 

[johntheo]

Doesn't seem any spaces for the air to get in for measurement either, the aperture in the rear is hard up against the wall, strange.

 

[johntheo]

Was informed that the above type does not need any "slots" to measure the room temperature but swapped it for a electro/mechanical type, a EPH, with a (fixed) hysteresis of 1 degC.

 

[adamstanly]

I think making a new mount that might give it more air circulation will solve the problem.

 

[johntheo]

It acted (up) exactly the same when removed from the wall and left just hanging there so I I just returned it.