Firebird 50/70 oil boiler problem

reubenreuben

I use this for heating water and central heating radiators.

Noticed recently that when switching on to heat water only, the boiler fires up for a few minutes then cuts out. After a few minutes it cuts in again. It does this even if water is not at the set temperature. It does eventually get the water hot but takes ages.

When using it for central heating it is on until the radiators get hot.

So why is it not doing same when heating water only?

Wearb

Balancing valve almost closed. Or restriction in pipe work.

jimf

do you live in an area with bad limescale problem

Billy Bunting

reubenreuben wrote: »

I use this for heating water and central heating radiators.

Noticed recently that when switching on to heat water only, the boiler fires up for a few minutes then cuts out. After a few minutes it cuts in again. It does this even if water is not at the set temperature. It does eventually get the water hot but takes ages.

When using it for central heating it is on until the radiators get hot.

So why is it not doing same when heating water only?

Sounds like a gravity hot water system, this would mean it only uses the circulating pump with heating but on hot water only it allows gravity to do the work, hot water rises and as such can circulate, although slowly.

Walter Becket

Some pictures would help

reubenreuben

jimf wrote: »

do you live in an area with bad limescale problem

Fairly bad, taps scale up quite quickly