Ecotec Plus 831 & Honeywell CM721/BDR91

[steviebobs]

Hi again all. A little advice please!

I have the above combination and have it normally set on ‘auto’ with programmed options. If I am going away for some time, I put the room stat on ‘OFF’ knowing it maintains a frost stat at 5 degrees,

After going away for 2 weeks, returning on 11th Nov, I entered the house to find it nice and warm! The room stat was still on OFF but displaying 19.5 degrees! (As it would if it was still on AUTO). I also have an extra 100 gas meter units usage similar to that had I been at home. By chance, one of my cctv cameras covers the flue and indeed, the flume was apparent every 10/15 mins of the ‘normally on AUTO’ period for that two days prior to arriving back home (no earlier data unfortunately). It looks like the OFF has been ignored and it has been running on AUTO. A total guess!

My questions.

Have I overlooked something?
Is it likely the unit is faulty?
If so, what would be a suitable replacement, preferably that will link to the existing BDR91 relay box?
If not possible, what other alternative? I realise that BDR91 is simply a switch and not intelligent, I am ok with that.

Thanks for reading.

 

[CountryFan]

Is the preheat function active on the boiler?

 

[steviebobs]

Hi CountryFan, thanks for that quick response, from the front panel I have determined that the preheat function or 'Comfort Mode' is off. Tks.

 

[CountryFan]

Were any lights on the receiver at the time? Any motorised valves? Or perhaps the pcb link has been left in?

 

[steviebobs]

Hi, I should have checked but 'think' the green receiver light was on, no motorised valves. PCB link? - not sure. This has worked for years before on previous 'holidays away'.It was a deal colder this time, but if the frost stat was 'initiated' by a -5 occurance I am sure it should not have wacked it up to 19.5 degs !! (LoL)

 

[CountryFan]

Ok, little bit of better information. When was the last time batteries were changed and good alkaline ones?