[Closed] Any Plumbers here?

is there not a tank in the roof with a ballcock type valve in it?

There is, the feed to that works fine. There's a separate larger tank which feeds the domestic hot water which works fine too

so where on this diagram do you think the problem is?

[img] [/img]

the system cold feed from the tank down?

Is the "system cold feed" labelled correctly?
Sounds like a problem with the F&E tank/valve/etc to me.

Wwaswas,

The issue is I think somewhere between the pipe at the base of the f and e tank to the T junction on the CH circuit

F and E valve is fine

Can you get to the pipework as close to the valve as possible and squirt some cold water up to the F&E tank at mains pressure, that should clear any blockage.

I was going to suggest pressurising the system by using the overflow pipe to the expansion tank to put water into the system from the other end - should reverse flush the feed pipe. you could just put one of those 'push-to-fit' garden hose tap connectors with a jubilee clip on the overflow pipe end.

Note: I am not a plumber and have no idea if this will cause your house to fall down or not.

Ah!

Up in the loft there are some old hose pipe lengths so I guess this might have been done before!! I reckon it's on the pipe that's labelled System Cold Feed.

Was wondering how I could eradicate the blockage.

Mrs Mikertroid is keen for me to leave it well alone as She feels I will blow the house up. As a typical red-blooded male I of course know better and will no doubt replaceiles of pipe work at greater expense!! I'll keep you posted!

There might (ought to) be a gate valve on the F+E pipe from the tank to the CH circuit.

Check it isnt closed/seized closed.

F and E valve is fine

Wrecker: yes.

Stoner: will check, thanks! Didn't consider that

The gate valve feeds the input to the F and E tank; that all works fine. The problem must be from the F & E outlet to the CH circuit.

I would try and get some pressure back up the FandE pipe - it may just be an airlock or soemthing.

Could you not just do the 'fill from a drain point' thing but with the normal vent pipe blocked to force water up the fande pipe?

Hi Mike
This is a fairly common problem
Almost certainly the blockage is at the joint where the System cold feed joins into the heating pipework. The blockage often can extend 6" or so up the pipe but above that is usually clear. There is often a build up of either side joint into the main pipe.
I wouldn't recommend trying to blast it out of the way as all the hard bits will just find their way into the system and may cause problems in the pump etc.
I suggest you get the system drained down and chop the offending section out. Compression joints and gate valves should be used so the section can be inspected / cleaned again in the future.
Poor pipework layout is often the root cause of this build up. This should be put right as well. Whilst the F&E tank is isolated from the system give it a really good clean flushing all the dirty water down the system cold feed pipe and into a bucket.
This whole job can be messy and time consuming. The last one of these i did took 4 hours. The biggest danger when refilling and recommissioning the system is that you will burn the pump out due to an air lock so get a Plumber to do it unless you are absolutely sure you know what you are doing.
Hope this helps, Mark

I'm not reading all of the above. But it'll almost certainly be where the cold feed tees into the system. You need to access it and cut it out.

There are other options, to get it going, like combining the feed and vent, none of which are ideal, or even in some cases safe to do so, so if you don't know if that the boiler is safe to combine the feed and vent on, then assume it isn't.

Mark/Paul,

Thanks, it seems to be what I'd guessed then, but having located the T junction, I'll get a pro to do it. Mainly to appease the wife! In principle, I'd be happy to do it, having replaced various bits already.

Thanks again,

Mike

Stick a magnet on the Tee to confirm. If its blocked, you'll feel it trying to stick.

I asked in plumbing class tonight for you, and teacher said exactly the same as those two know-it-alls up there did ^

😉

drain water from system first
have always just removed the expansion tank connected mains water onto cold feed to system with a stopcock in-between
put a bucket under the vent just in case water comes back up
then slowly open the stopcock to use as little pressure as possible
if you have been back filling your system your system is going to be full of crap anyway so a little more is not going to cause any more harm but a good flush through after is going to be needed
if access to pipe work is easy then cutting out is an option but have found in most cases warms and cans come to mind

Stoner,

I'm enjoying the DIY plumbing I'm doing, is your course a home maintenance one or a pro one? I wouldn't mind taking this further.....!

Its a City & Guilds 6128 Heating & Ventilation (effectively the plumbing 6129 course without lead work), so a trade one. Then I move on to NVQ2 portfolio in a year's time. Then with that I can do my tickets for gas, oil, un-vented and MCS. And then I want to do HETAS. And maybe the Part P Defined Scope as well.

Hmmm, I think I'll have to stick to my day job for now but will look at home maintenance course in the meantime.

mike were are you

Near Salisbury

paulo is spot on 99 % of the time the blocakage is wthe T where the feed joins the circuit cut it out and see. drain all the water above the t in the ch pipework and plug the outlet to the f and e tank in the loft simply cut the T out if its solid with crud job done replace and your good to go.. sounds simple like that doesnt it..

iv used my rothenburg haudraulic pressure tester to unblock them , it works a treat. if your ever near swindon you can borrow mine .

Mark,

Might take you up on that;work takes me near Swindon regularly.

Before you start paying plumbers to come In try finding the previously mentioned tee and gently tap that section of pipe, if your lucky you'll hear the water flowing down the cold feed to the heating system afterwards...

mike, any time mate just post me its easy to do ,i can show you