Puma 80 blocked communication pipe !

[Agile]

I went to a Puma yesterday expecting to find a failed EXV.

The problem was in fact a blocked communication pipe between the boiler and the EXV.

Luckily this the first case I have encountered on this model. Unfortunately, the connection to the EXV is inaccessable so it cannot be replaced.

The boiler end of the communication pipe is a narrow elbow at about 8 mm.

Has anyone had much success at clearing a blockage on this pipe from the front?

Just to put the strength of the blockage in perspective, it withstands 1 Bar in the EXV or in the boiler !

Tony

 

[nickso]

im struggling to picture this, is the pipe not accessible from the rear?

 

[twgas]

never had that on a puma - but why not pump more pressure into vessel, can always reduce it again if successful

 

[Agile]

The pipe goes from the right rear corner just behind the PRV, up via an elbow and then through a hole to the rear section containing the EXV.

The boiler is high up in a broom cupboard with a vertical flue so there is no prospect of removing the EXV ( without taking the boiler off the wall ) to get at the connection onto the EXV.

I wonder how BG would tackle that or do they always check enough clearance above to remove the EXV in situ before accepting a boiler on cover?

Tony

 

[Agile]

never had that on a puma - but why not pump more pressure into vessel, can always reduce it again if successful

I hadn't found it on a Puma either, until yesterday!

If 1 Bar does not budge it then I doubt that 2 Bar would either.

Of course for all I know the diaphragm may well be fully inflated and not exerting any pressure on the blockage.

In any case 1.8 Bar in the boiler does not budge it either!

Of course just a small blockage in the connection to the LP switch is able to withstand the full boiler pressure!

Tony

 

[nickso]

I wonder how BG would tackle that or do they always check enough clearance above to remove the EXV in situ before accepting a boiler on cover?

Tony

nope, it wouldnt be a concern at a first visit.

i would take the boiler off the wall or fit an external vessel if the customer agreed.

 

[Vic Spanner]

i would take the boiler off the wall or fit an external vessel if the customer agreed.

Same here.

 

[ChrisR]

Yes I've had that, and cleared it, and posted how, on this site, as well as telling Tony on the phone one day!
Folded over some Bowden Cable and put the cut ends in a drill.

OH LOOK:
//www.diynot.com/forums/viewtopic.php?p=736027#736027

 

[nickso]

Yes I've had that, and cleared it, and posted how, on this site, as well as telling Tony on the phone one day!
Folded over some Bowden Cable and put the cut ends in a drill.

OH LOOK:
//www.diynot.com/forums/viewtopic.php?p=736027#736027[/QUOTE]

clever, ill have to remember that.

 

[Agile]

Yes, I remember that.

But Chris sometimes seems to have more luck with unblocking things than I do.

He even has some brake cable to use.

Whilst thinking about that, does anyone know where to get long lengths of the woven steel cable as I need some for my up and over garage doors.

Tony

 

[ChrisR]

Come off it Tony if you'd remembered you'd have tried it! Or at least said you didn't have any brake cable!
I didn't have any at the time, I just got some from Halfords. It would clear ANY blockage on that pipe. It drills through solid blockages in feed pipes too.

 

[spacethegas]

i've got left over cables from fitting ilfe fires, cost zero.

+ wires for hanging net curtains or attaching c/stats are handy especially for unblocking cold feeds, fit in the cordless drill a treat & cost zero.

 

[Steve69the69Gas]

BG would prolly recommend a powerflush as per fecking normal

 

[baxpoti]

If is 's not practical to lift the boiler off the wall, fit another expansion vessel on the return pipework.

 

[nickso]

BG would prolly recommend a powerflush as per f*****g normal

as they should if the water quality is poor, ignorance is not your ally.