Hi, we have an external Heatslave 18/25 and our central heating has been happily controlled by a Honeywell programmer for the last 4 years. At the moment we have been using the Honeywell it on its 'manual' settings where we set a target temp and if the temperature is too low on the CM927 unit, it sends a signal to the wall mounted unit, a green light comes on and the boiler fires up.
I'm not sure I have inadvertently 'done something' but on Friday evening I bled a radiator as it had been quite cool for a while. Heat returned to it so I went to check the boiler pressure and noticed it had dropped a bit so I topped it back up to the required pressure mark. All normal stuff so far.
At the end of the evening we normally turn the Honeywell to the 'off' position. That is what I did this particular evening and, as always, heating shut off and everything began to cool down.
When I woke the next morning the rads were hot, clearly on. Thinking I might have forgotten to turn the Honeywell unit off, I checked it and indeed it was off. I next checked the Honeywell receiver unit for the green light and that was off too. However, the boiler itself was on. I couldn't fathom how to turn it off so I switched the boiler off and on again and it immediately wanted to fire up. I turned it off and on again a couple of times and it still wanted to fire up so I left it and went inside. After a while it turned off by itself.
I noticed that the Honeywell could still control it using the manual settings and after a couple of tests to make sure it was firing up and shutting off using the Honeywell unit, I concluded it was maybe a glitch and now everything was ok.
Last night, I did the same, turned the Honeywell 'off', boiler turned off and I went to bed. This morning, the rads were hot again so checked the Honeywell and the receiver unit...both off.
I am guessing that, although I can still control the boiler using the programmer, it ALSO seems to be operating independently of it i.e. as if the programmer does not exist and maybe it is getting the message to fire up from the rad valves.
Any ideas what this might point to before I call the plumber out? This all started happening since I bled that radiator and re-pressurised the system.
Thanks
Dan
I'm not sure I have inadvertently 'done something' but on Friday evening I bled a radiator as it had been quite cool for a while. Heat returned to it so I went to check the boiler pressure and noticed it had dropped a bit so I topped it back up to the required pressure mark. All normal stuff so far.
At the end of the evening we normally turn the Honeywell to the 'off' position. That is what I did this particular evening and, as always, heating shut off and everything began to cool down.
When I woke the next morning the rads were hot, clearly on. Thinking I might have forgotten to turn the Honeywell unit off, I checked it and indeed it was off. I next checked the Honeywell receiver unit for the green light and that was off too. However, the boiler itself was on. I couldn't fathom how to turn it off so I switched the boiler off and on again and it immediately wanted to fire up. I turned it off and on again a couple of times and it still wanted to fire up so I left it and went inside. After a while it turned off by itself.
I noticed that the Honeywell could still control it using the manual settings and after a couple of tests to make sure it was firing up and shutting off using the Honeywell unit, I concluded it was maybe a glitch and now everything was ok.
Last night, I did the same, turned the Honeywell 'off', boiler turned off and I went to bed. This morning, the rads were hot again so checked the Honeywell and the receiver unit...both off.
I am guessing that, although I can still control the boiler using the programmer, it ALSO seems to be operating independently of it i.e. as if the programmer does not exist and maybe it is getting the message to fire up from the rad valves.
Any ideas what this might point to before I call the plumber out? This all started happening since I bled that radiator and re-pressurised the system.
Thanks
Dan