Another 'Pumping Over' question......

[GeorgeUK]

Hi all,

First post so please be gentle.

I know this question has been asked numerous times but as each system is slightly different, here goes.

I have an 8 year old Glow Worm micron 50F in my first floor bathroom airing cupboard, along with the hot water cylinder fitted at the same time. The Expansion Tank is in the loft above placed at floor level, the cold water supply tank for the the hot water cylinder also in the loft was raised about 5 feet a few years ago, to give me better pressure for the shower. The 2 year old pump is currently set to the lowest of three speeds. The Expansion pipe is about 1 foot to the top of the bend above the water level in the F&E tank.

Very Hot water is pumping over when the system is heating the water, this is at nearly full flow when the pump speed is on 2, & a bit less when on speed 1.

I would appreciate your help & advice regarding this problem.

Thanks in advance.

 

[JohnD]

you've read the other posts and tried the advice they gave.

so it has only recently started doing this, and it did not start after you had alterations done, and you have tried turning down the pump speed, and you have tried de-sludging it with X400, and you have adjusted the water level down in the F&E, right?

If you've already tried al the things recommended in the other posts and none of them worked, you'd better start asking friends and neighbours if they can recommend a good local plumber.

We have no more advice that wasn't in all the other posts you've already read.

//www.diynot.com/forums/viewtopic.php?p=770910#770910

//www.diynot.com/forums/viewtopic.php?p=891831#891831

//www.diynot.com/forums/viewtopic.php?t=38902

//www.diynot.com/forums/viewtopic.php?t=38902

 

[GeorgeUK]

Thanks JohnD,

I will try the X400 option first, there is prob only 100mm between the expansion & the feed pipes which are both before the pump, so maybe extending the expansion pipe above the tank may not achieve much?

The expansion pipe is 22mm & the feed pipe is 15mm, would this make a difference?

Many thanks.

 

[JohnD]

The expansion pipe is 22mm & the feed pipe is 15mm, would this make a difference?

That's how it should be (BTW it is called the Vent pipe, if you mean the one curved over the top of the F&E)

 

[liverpoolboy]

obviously you're f & e vent pipe doesn't have enough "dry head" : should be 450mm minimum above the water level to cater for pressure surges created by the pump.

also there should be a minimum of pump head (usually 5M0 divided by 3, so just over 1.5metres from your circulating pump to your water level in the f & e to prevent undue movement of water.

 

[GeorgeUK]

Thanks both for your input,

It wasn't obvious to me initially hence the post.

Its great to have some helpful experts willing to give advice.

Thanks again.