Pumping over problem

[ritchie12345]

i came across a similar problem. so i solved it by connecting feed pipe to expansion pipe. the problem now is that the water in loft tank gets warm. i presume it is acting as a loop now. i'm worried about the tank maybe melting, or even maybe excessive evaporation causing top up of fresh water thus corrosion in the system over time. any plumber out there help me

 

[seco services]

sort out why its pumping over
yes the f/e tank will only take a certain amount of hot water.

put it in your own post and tell us what system you have and how the fault started etc.

 

[Blooflame]

blocked cold feed mate, the pipe from boiler must turn horizontal before the vent (22mm) rises followed by the cold feed (15mm) - use an airject would do the trick. If all those factors are observed then the cold feed is usually blocked

I have been called in to a job to look at a heating system that has a serious pumping over problem. It is a two story house with boiler on ground floor, pump and three way valve in airing cupboard on first floor. The cold feed and vent tee into the common flow in airing cupboard. (seperatly both 22mm)

The system has been flushed and shows no signs of any blockages, but as soon as the pump goes on in either heating or hot water it shoots out the 22mm vent pipe even when cold.

I reckon I have been called in to sort a problem that never has been right since installation as the water in expansion tank was very brown.

Any suggestions, I no it's the weekend but I would be gratefull for any comments.

Will making the expansion pipe higher make any difference?

 

[iep]

Following this post with interest. For clarity, can people state where they think the blockage might lie? I've labled the attached open vent diagram with points A, B and C. Iwould have thought that point C would have to be blocked to cause constant pumping over?

Untitled

• iep
• 16 Nov 2010
• 3

Cheers,

iep

 

[45yearsagasman]

If I was doing the job I would cut out and either clean or replace the whole H section.You will find most of the blockage below B but there will be crud in the horizontal pipe from the LH tee and up to the 1st pump union.Cut below LH tee,and 300mm up open vent and cold feed and disc pump union and remove the whole section.Examine and clean or replace.You can use compression fittings to refit if you are not confident soldering.

 

[Blooflame]

Blockage is usually where pipe B meets pipe C. Pipe A should not rise directly upwards from the vertical, rather should be from the horizontal after about 200mm (not usually practicable). As Gasman for 45yrs says, cut it all out. Use an airject.

If I was doing the job I would cut out and either clean or replace the whole H section.You will find most of the blockage below B but there will be crud in the horizontal pipe from the LH tee and up to the 1st pump union.Cut below LH tee,and 300mm up open vent and cold feed and disc pump union and remove the whole section.Examine and clean or replace.You can use compression fittings to refit if you are not confident soldering.