intermittent hot water

[billyjack]

Fault intermittent hot water

Symptom no feed to coil in tank ie breaking vent connection from top
of coil nothing comes out, although sometimes is ok
also nothing comes out of vent from boiler

Cold water feed to system seems ok as radiators can be filled and
feed pipe gets hot

 

[breezer]

more information

what make model of boiler

type of boiler

etc................. ( got fed up typing same old thing)

 

[oilman]

etc................. ( got fed up typing same old thing)

If you get a stickies/post-it freeware utility, you could have the oft used phrases all over your screen ready to paste whenever you need them. (And a damned irritation all over the place when you don't)

 

[ChrisR]

bj do the bleeding with the heating & pump off, & make sure any motorised valves are in the "man" position. Water should come out at all bleed points. If not then theres a blockage, which could be air in a horizontal pipe.

 

[billyjack]

The boiler is a glow worm hideaway approx15 years old

 

[ChrisR]

I repeat, "Water should come out at all bleed points"
Well?

 

[billyjack]

I repeat, "Water should come out at all bleed points"
Well?

I guess there is a blockage (intermittent) as some times
water comes out sometimes none.
Is there any additive I can use to flush out system

 

[oilman]

Chemicals aren't much use if you have a blockage, as there is no flow to get the chemical to the blockage. It usually needs clearing mechanically after cutting the pipes.

 

[billyjack]

Chemicals aren't much use if you have a blockage, as there is no flow to get the chemical to the blockage. It usually needs clearing mechanically after cutting the pipes.

I was thinking of breaking feed supply and feeding domestic water supply
in . Being under pressure it may force out blockage.

 

[ChrisR]

I have a bit of hose with fittings to join the tank's mains feed to the vent pipe - the grot usually pumps up into the tank. It's usually the bottom of the feed pipe where it collects. But yes sometimes you have to cut pipe out.