Also, I'm now fairly sure the rattling noise is the pump. Grundfoss 15/60.
If you shake the pipe when it's off you can definitely here something rattling around inside . I assume this means it's on the way out, it's also noisier than it used to be when in operation.
Did some further checks :-
Mid position is working
If CH is satisfied, valves stays in CH position
If HW satisfied , valve stays in HW position.
I assume this is normal ?
Only problem is when HW satisfied my pump overrun goes on for ages as the water though the boiler is just...
V4073A1088 28MM HONEYWELL MOTORISED MID-POSITION VALVE
At rest with no demand from heating or HW, the motor is very hot. Is this normal ? Am also fairly sure the mid-positon for CH/HW demand is not working.
Also, I am sure the valve is rattling inside the pipework. Have tried adjusting the...
They said assuming wiring correct pump won't overrun unless boiler stat senses >70c in
Max temp on this model is about 82c with stat on max, not sure on min ?
Maybe stat needs replacing, although it seems to work OK for normal boiler operation
yes pump is wired to boiler, online glowworm manual (2004) describes a normal pump-overrun
The 1998 manual I have says overrun will work when boiler stat set to max. However, it doesn't , but only comes on as previously described.
I wonder if Glowworm tech support can confirm how it's...
No I dont think it ever has. Just occasionally comes on when I suspect it detects boiler is too hot.
Definitely two types of pcb - see http://www.plumbtraders.co.uk/product/glow-worm-s900817-pcb-alternative-kfb-see-rems/#.UpSeYMTIak4
I have a Glow-worm Ultimate 120FF 1998, one fuse PCB
I do not seem to have a "normal" pump overrun, ie when controls stop calling for heat the boiler/pumop switch off. This can result in heat building up inside the boiler and lots of gurgling etc.
Very seldomly, the pump will come back on...
Now ready for my DS40 treatment.
I think I would like to isolate the boiler as far as possible, is this a case of closing the TRV's and lockshields on most of the rads ?
Also what is the best length of time to circulate for, instructions are a bit vague.
Have a Glowworm Ultimate 120ff, heat exchanger is fizzing and gurgling and kettleing
Can I add treatment to the system to cure ? or do I need a powerflush ?
I have drained down the system and added inhibitor in the past etc so know how to do it.
If I can do it manually which chemicals...