Another Boiler Kettling.

[keego]

Only thing is, it's my own boiler!. Up to now I've tried power flushing it from a radiator & X200 with no effect, after that I gave it a power flush from the pump with all the rads & HW coil off ( left it on for 2 hours ) this cured the problem for all of 3 days.
This all started after I changed the bathroom rad to a towel rail, I never drained down because I used bungs, one valve was a straight swap the other needed a reducer soldering on but otherwise that was a straight swap as well.
The boiler is a Baxi Solo 3 50PF which is less than a year old ( the whole system is only 6 years old ), it's on a Y plan fitted with a bypass, the area we live in is a soft water area but I still have a scalemaster Gold fitted on the rising main, it's always had X100 in it until now, I've put Salamander system inhibiter in it this time..... change of employer
All suggestion gratefully accepted as I'm starting to lose the plot on this one, the boiler is below my bedroom & I'm getting tired of being woken up every morning by the bloody thing.!

 

[bab]

As long as u have 1 rad without a trv u dont need a by-pass on a Y plan.If the boiler is only a yr old & has allways been inhibitered it shouldnt be scale.How close to the heatexchanger is the boiler stat sensor.Does it ever o/heat.

 

[keego]

Yep, I know about the bypass & TRV but the system was installed with trv's upstairs & WH valves on all the downstairs rads & they still fitted a bypass, not altogether a bad thing because it gives me the option of fitting trv's downstairs.....eventually.
Up to now the boiler has never gone t O/H & the boiler stat is on the Flow about 50mm from the H/E.

 

[bab]

Hav u got good circulation around the system. is the pipework off the boiler in a self venting setup or does the flow pipe slope down a little allowing a little air to be trapped in the boiler. These boilers have street elbows connecting the pipework to the heatexchanger. once took me 10 hrs to find the flow street elbow partley blocked when the installer had tried to wrap ptfe around the street elbow compresion ring. U need a crystal ball nowadays.

 

[keego]

Hi bab, the pump is Ok, I changed that about 18 months ago & I've tried changing the pump speed & it makes a difference for about a day & it kicks off again. there is an air separator fitted to the system.
I know the pipes to the boiler are clear as I fitted the boiler myself & I never use ptfe on conex joints ( can't understand why people do? )
as for the pipework I suppose they could have dropped a bit when I fitted the boiler but they are well supported on the joists upstairs.
i just can't figure out why it's started now when all I did was swap a rad.?

 

[keego]

Sorry, just giving this one a little bump to the top.