What have I done!!!

[danoid]

So had the heating on, luvly jubly.

I then got bored and wanted to find out if the radiator pipes in the kitchen actually work (been removed since we moved in, so no radiator just the trv not connected to anything)

To my suprise it worked but got some nasty black water coming out, I then hear the boiler click off and cannot get it started!!!

It's a non combi boiler system. I went into the airing cuboard and where the pump is, there's a valve pointing up. I undone it and whsssp loads of air and bubbling noise. I thought laughing this will fix it, nope!

I went round upstairs radiators and bled them and again loads of air, but boiler not kicking back in.

The pump was spinning but sounds gritty, is the pump clogged? Would this cause the boiler to not kick in?

I undone the large inspection screw on the pump but looks alright but no dribble of water.

So got no heating or hot water and feel really sick, what could be the problem?

Thanks

 

[JohnD]

Is there a pressure gauge on the front of the boiler, or is there a feed and expansion tank in the loft?

If F&E, is there any water in it? Is there a lot of mud at the bottom?

 

[danoid]

It's got a tank in the loft, a little one.

It's full of water, it has some mud stuff but only small amount

 

[JohnD]

then you almost certainly have a blockage in the pipe from the F&E tank, where it joins onto the main circulating pipes.

Bale out the F&E into a bucket to take out the dirty water and the mud, and let it refill with clean water. After a day, try bleeding the highest radiator in the house to see if water squirts out (it probably won't) if the blockage is not total.

The blocked pipe will have to be cut out, by you or a plumber (you do not need a boiler engineer) and replaced with new, and then you need to run at least a chemical clean to remove some of the existing sludge and sediment. It would be preferable to also add a system filter, which will cost about £100.

The cleaning chemicals are quite cheap, if you can DIY simple plumbing. However they will not work until you have cut out the blockage and restored circulation.
Turn off the boiler, and ensure the pump is not running, until it is fixed.

 

[danoid]

How would running an unused radiator pipe cause this though?

I just opened up the unused radiator a minute ago and water stopped coming out and the boiler came on, went off again shortly afterwards grr
Still not sure how a airlock or whatever happened as I only undone the flow pipe

 

[JohnD]

it isn't an airlock, it's a blockage which prevents the system refilling with water when you bleed it or let water out of those pipes you mentioned resulting in the system being partially empty of water. It is actually very common.

Turn the boiler off like I said, or you will need a new pump as well.

Post some photos of the pipes around the cylinder, the pump and the boiler, especially where the 15mm pipe from the F&E tank joins onto the bigger circulating pipes.

 

[danoid]

I'll be able to get some pictures tomorrow.

I went in the loft and there is a thick pipe coming from the little tank, it goes down into the airing cupboard, from there it goes into a t, one side goes in a little copper cylinder, no taller than an index finger

The other pipe goes to the pump.

Around here I can put a magnet and it sticks, which is strange

 

[JohnD]

it is sticking to the black iron oxide, a result of corrosion of the steel radiators, which has collected there and caused a blockage. You presumably looked up the magnet test for sediment blockage. As I say, it is very common. It tends to form a mass mixed with limescale and goes very hard, not sludgy.

The little cylinder is intended to trap air bubbles, but is probably clogged solid.

 

[danoid]

As a ball park figure, if it's allowed on here, are we talking less than £250?

 

[JohnD]

possibly. Ask around for a recommended local plumber to cut out and renew the clogged bits, and do the chemical clean yourself afterwards.

 

[slapper]

As a ball park figure, if it's allowed on here, are we talking less than £250?

No, abaht four fousand

 

[ollski]

If you just want to get going again cut a few feet of hose pipe stick it down the open vent pipe above the small tank in the loft and hold the other end over where the water comes out of the ball valve. Get someone else to bleed the rad as you fill the system by opening the valve. If you're feeling braver and the open vent is 22mm then simply tee the 15mm feed into the 22mm vent pipe in the airing cupboard and cap off the open end of the old feed. Or to start off try hitting the blocked tee with something like a spanner to see if you can break off some of the blockage.

 

[danoid]

It got fixed by a plumber on Sunday, but having to come back today as one if the copper elbows is leaking a small drop now and again, nothing ever goes smoothly and worry free for me