Frozen pipes caused a fire!

[ARWadsworth]

Todays job was wiring up a new solid fuel boiler. The old one was destroyed last week (along with the boiler room).

The owners of the house had gone away for a couple of weeks and were due to arrive home during the cold spell. As a welcome home surprise the nextdoor neighbour lit the boiler so that owners would not be cold when they arrived home. Unfortunately the pipes were frozen solid (and probably the pump) when he lit the boiler. As the heat had nowhere to go the boiler exploded setting the boiler room on fire.

The neighbours are still talking to each other.

[dom]

Was this was a pretty old installation with no pressure release close to the boiler?

I thought that some sort of overload protection had been standard since at least the 1960's?

And surely a solid fuel installation shouldn't be dependent on a pump for primary circulation?

[cynic]

If the pipes were full of ice there couldnt be any gravity circulation and unless the pressure relief valve was VERY close to the boiler the same plug of ice would prevent it relieving the pressure. Theory falls down when it meets reality.

[robgraham]

Yes but if the pump was frozen then the pipes to the relief radiator would have been frozen too.

The pressure release is an interesting one as I have an external oil boiler which doesn't have such that I know of (and I installed it), but it does have a frost stat that keeps the heat exchanger from freezing. In writing that I've just realised that a link between the frost stat and the house pumping system would be a good idea such that the pipes through the wall would be kept clear of ice regardless of how much insulation they have.

[ARWadsworth]

I have no idea what the old set p was. I only wired the new boiler up. The old one was thrown in a skip on Monday. And it is the 1st solid fuel boiler that I have ever wired up (and I live in a coal area).

To be fair, I found it quite an interesting job (something new to me).

Is the pressure valve you refer to just to discharge pressurised water?

[Davey]

My folks purchased their first home, a new build, in the early 60's. It was a freezing cold winter and my Mother went to the house to wait for a furniture delivery or suchlike along with my Dad's sister for company. Cold as they were, they decided to light the coal fire in the lounge and warm up a bit, sitting on a couple of kitchen chairs. They left the room for literally a couple of minutes and heard a very loud bang. They tentatively opened the lounge door to be greeted by the sight of the remnants of an explosion caused by the frozen back boiler.

If they hadn't left the room, there could have been serious injury or worse.

Fortunately, the builders were very understanding and fixed the damage for free :o)

True story.