Waterfall from overflow pipe - help

[britishboy7]

Just went to lock front door and heard water running outside, there was a continual stream of water from the overflow pipe of the small water tank in the loft (header tank?), it’s stopped now. We had 2 new radiators fitted today in kitchen, and the plumber drained the system. Since filled it, bled all the radiators in the house and gone.

The waters stopped now, but what would of caused it? We’d had the heating on full for the last 3 hours to test the radiators and I went round bleeding them again, all ok. Turned the thermostat down ready for bed, heard a lot of water gurgling sounds then the waterfall outside...

Any ideas please? But concerned and can’t get hold of the plumber (go figure)

 

[terryplumb]

Problem with water level setting or ball valve in loft tank .

 

[dilalio]

When system was drained and refilled, some debris in the supply pipe may have been pulled through to the ball valve and is now stopping it from closing properly when level in the tank rises and lifts the ball float, However! This would normally result in a steady trickle/stream from the overflow rather than a torrent!
Pumping over could be occurring which is a resistance and expansion issue!
Try seeing if the ball valve is shutting off properly first, then report back.

 

[britishboy7]

THenks guys, I’ll check the valve is closing fully as soon as I’m home from work.
It seems to do it either when the heating comes on, or goes off, does this make sense?

 

[britishboy7]

Watched the water tank and got a friend to turn the heating off and the small tank began to fill from a different pipe (NOT the one with the bell valve), but from an upside down ‘U’ shape pipe that also feeds into the small header tank? What’s this pipe please?

 

[terryplumb]

Its the vent / expansion pipe ,systems pumping over .

 

[JohnD]

it's probably sludge and sediment blockage. Very common in old open vented systems especially if they have been neglected.

first and cheapest step is to try a chemical clean. A bottle of Sentinel X400 will cost you about £15 and is easily done as you have a feed and expansion tank in the loft.

Bale out the F&E tank first, remove all the mud (this may have been a factor in your current blockage), add the chemical before turning the water back on.

If it loosens the blockage, run it for 4 weeks then drain and rinse to remove the loosened sediment

If it doesn't work you will need a plumber at additional cost, to cut out and renew the blocked pipe and/or do a powerflush. It will cost some £hundreds so I'd try the DIY chemical first. Sadly it is better to clean the system before it actually blocks.

 

[dilalio]

F&E must have been full of $|-|it that went down the feed pipe into the system when it was drained.

 

[britishboy7]

it's probably sludge and sediment blockage. Very common in old open vented systems especially if they have been neglected.

first and cheapest step is to try a chemical clean. A bottle of Sentinel X400 will cost you about £15 and is easily done as you have a feed and expansion tank in the loft.

Bale out the F&E tank first, remove all the mud (this may have been a factor in your current blockage), add the chemical before turning the water back on.

If it loosens the blockage, run it for 4 weeks then drain and rinse to remove the loosened sediment

If it doesn't work you will need a plumber at additional cost, to cut out and renew the blocked pipe and/or do a powerflush. It will cost some £hundreds so I'd try the DIY chemical first. Sadly it is better to clean the system before it actually blocks.

Thanks John, we had a power flush 3 years ago when we moved in and the 3 way valve/switch and pump in airing cupboard replaced by BGas, and when the system was drained a few weeks ago to add a radiator the water that was drained out the drain tap (outside the front of house, comes out beside an air brick) was crystal clear. And we added some Ferox to it when we refilled it 4 weeks ago?

The whole lots coming out next week as we’re having a new combi boiler fitted, will the problem go away then once combi is fitted?

 

[JohnD]

not if you don't fix it.

the installer will probably insist on a powerflush and fitting a system filter. Your current pumping-over problems will be oxygenating the water and accelerating corrosion. This has to be cleaned out before the new boiler is fitted. Modern boilers generally have narrower waterways and are more easily blocked than old ones.

The guarantee will not cover problems caused by dirt and sludge.

 

[britishboy7]

F&E must have been full of $|-|it that went down the feed pipe into the system when it was drained.

Dilalio, excuse my ignorance what would cause that amount of sh1t to get into the tanks?

 

[britishboy7]

not if you don't fix it.

the installer will probably insist on a powerflush and fitting a system filter. Your current pumping-over problems will be oxygenating the water and accelerating corrosion. This has to be cleaned out before the new boiler is fitted. Modern boilers generally have narrower waterways and are more easily blocked than old ones.

The guarantee will not cover problems caused by dirt and sludge.

Could it need powerflushing again, even though it was done 3 years ago?

Also, we had an Adey Magnaclean filter fitted when it was powerflushed

 

[JohnD]

That's interesting.

When you empty the Magnaclean, what do you get out? How often?

 

[dilalio]

Dilalio, excuse my ignorance what would cause that amount of sh1t to get into the tanks?

Potable water (with all the added treatments); air; various metals; heat; thermal shock; turbulence; stagnation; various chemical reactions; and Sod’s law.