Drained heating - now the pump is jammed.

[RigidRaider]

When will I learn not to undertake heating and Land Rover maintenance jobs on a Sunday? I drained some water out of the system yesterday so as to top up the Fernox. Then discovered that my drain cock, installed 8 months ago, wouldn't turn off. Closed all rads, drained the pipework and off to Sod-it-All for a replacement cock. Found that the little rubber washer in the cock had broken up, probably my fault for over-tightening it. Refilled system, tidied up and poured a cold beer.

Now this morning the CH pump is humming but there's not hot water. The boiler fired briefly but won't run.

Is it possible that the pump is seized with some muck that's got in? I cleaned out the header tank carefully before refilling but I guess the water movement could have disturbed sediment somewhere in the pipework.

 

[ChrisR]

Possible, but not very common. Have you had the screw out to try to turn the shaft with a screwdriver?

We're all inclined to overtighten drain cocks I think. They're pathetic things!

 

[RigidRaider]

Thanks Chris, I'll try that tonight.

Yes, amazing how an entire heating system can be sabotaged by one tiny piece of rubber!

The really amazing thing is that somehow it's my fault there's no hot water for 'er indoors to have her shower!

 

[ChrisR]

Of course it's your fault. You forgot(?) an Immersion Heater?

 

[RigidRaider]

Ha ha, yes, at least I remembered the immersion!

I removed the slotted cover on the pump and quite a bit of air spurted out before the water, then the pump spun into action. Are these pumps lubricated by water? Do they get airlocked?

All seems to be working fine now.

 

[Hairymary]

yes they can get airlocked esp when you drain them.

Yes they are water lubricated. Occasionally they can get stuck after a period of down time, a gentle coaxing tap with a club hammer gets them turning.

 

[Soggy_weetabix]

Yes, amazing how an entire heating system can be sabotaged by one tiny piece of rubber!

Thats why god invented bung kits

 

[ChrisR]

god invented bung kits

Pity his product development and quality control aren't up to much - not just for bung kits!

 

[RigidRaider]

Ah... the big hammer... Land Rover special tool No.1.

See also the big pry-bar, Land Rover special tool No.2 and of course the angle grinder, special tool No.3.

Thanks for the advice, as always.