Boilermate SP - Intermittent Heating

Hello all. Any asistance greatly appreciated as I am at my wit's end! Sorry if the post is quite long.

Briefly, we had a problem about 4 weeks ago when the heating wouldn't come on (or would but seemed to have a mind of it's own). Eventually, it appeared that the 3 way port valve was faulty and was replaced. Everything fine for a week but heating wouldn't come on (timed) on Monday morning. I pushed the manual lever on the valve back to the always on position and the heating came on. Came back from work and valve semed ok (it had gone to open posiiton by itself). However, heating stiill won't come on in the morning (timed) andI have to force lever to manual again. However, if I leave heating on all day/night is still won't be on in the morning with 3 way valve back over to hot water only position. The indicator tells me that the middle and lower stores are calling for heat and it stays that way for a good while. Therefore, from reading this forum it looks as though the store isn't getting (or staying) hot enough. I have noted problems highlighted in the forum re boiler issues. Ours is a Ideal HE12 (in the kitchen) but it does appear to be firing and staying fired. My wife did mention that ehating always seems to go wrong when it is cold which made me think that the bolier may be at fault but, as siad, the boiler is in the kitchen and does appear to be firing. It is set on max (6).

I am wondering if it could be a pressure problem? I came home the other rnight (gone midnight). The heating had gone off (although still switched on constant) but the pressure had dropped to less than 0.5 bar. When system is on it is at 2.00 bar. I opened the filler loop and pressure immediately jmped back to 2.00. By "immediately" I mean just that - it didn't flow and fill - it just jumped to 2.00.

As mentioned, any ideas most welcome.

Thanks.

Sounds like a sticky pressure gauge.
Also I have not checked, but you can.
If the store goes below 60c the heating will not work.
The BM 2000 does that.
Could be boiler pump not getting heat from boiler to unit quick enough.
Mike
MGC/H2O
Norfolk

Mike,

Thanks very much for replying (and so quickly).

I suppose there isn't much I can do with the sticky pressure guage other than replace it. However, is there anything I can do with the pump to check? By noise, it does seem to be operating ok.

I was thinking of draining as much as I can out of the system and refilling/bleeding to see if this helps. I thought that I may have some kind of blockage or lock somewhere. Perhaps I should vent the pump(s) too.

Thanks again.

Andy

Yes it might pay.
How old is the unit / system?
Always vent the pump and see if turning.
Feel the pump pipes and the return from the unit to the boiler.
Also the F & R on the boiler to.
Sludge can be a problem.
Mike
MGC/H2O
Norfolk

Thanks again Mike. The system is just coming up to 4 years old (new install in a new build).

I will try venting etc. over the weekend. The heating came on this morning (timed this time). The store does still seem to be calling for heat though but at least the bolier appears to be firing and stay that way.

Best wishes,

Andy