Is this boiler "fault" normal - video

[chrisw99]

Means that two of the three ports are free. That is all.

Please explain further, which 3 ports?

 

[chrisw99]

Here's my setup, exactly like this...

 

[Dan Robinson]

Think about a tee fitting. Now imagine if one opening is blocked.... How many openings are left?

One is your header tank.... And the other.....?


I thought you were an engineer?

 

[DP]

Think about a tee fitting. Now imagine if one opening is blocked.... How many openings are left?

One is your header tank.... And the other.....?


I thought you were an engineer?

Dan engineers and IT guys are a different breed.
Ours is hands on task, IT guys play with their keyboard

Sorry fella, could not resist it. Such a simple task, you do not see the problem.

Here is a tip for you.....do not get upset....... you know what a permanent magnet is, place this on the pipes connected to cylinder through which boiler water passes to heat water in the cylinder. Start at the cylinder and move magnet towards tee and beyond. Look out for areas that attract the magnet. That is where the blockage will be.

 

[Dan Robinson]

an example of said tee.

This system worked, sporadically for many years in this state.

 

[chrisw99]

an example of said tee.

This system worked, sporadically for many years in this state.

No magnetic attraction anywhere near the tee or any exposed pipe work. It did get very attracted to a nail sticking out of a floorboard, so at least I know my magnet works!

There's a bleed pipe just 2 inches from the tee and it was added later than the rest via push fit fittings, so once I've drained down I'm going to be able to disconnect that bit easily and prod around inside the pipework around there. Probably would do no harm to disconnect the connections into the cylinder and have a poke around the pipework there too. I had an idea I could just shove a hose at low pressure into the flow and return pipes if I do that and see what comes out the drain cock, would at least locate the blockage in either the flow or return if one trickled out much slower than the other.

Looking at your photo I guess F5 or X400/800 would do diddly squat to a pipe in that state?

 

[DP]

ChrisW, take it you tested both pipes.
The one with the bleed point will be the flow pipe
Other pipe is the return, might be an idea to check that too
Perhaps you already have

 

[chrisw99]

ChrisW, take it you tested both pipes.
The one with the bleed point will be the flow pipe
Other pipe is the return, might be an idea to check that too
Perhaps you already have

The bleed pipe is on the return not the flow (see diagram above in post #32). There was a small downward turn so any air in that area never made it up the cold feed to the tank, caused a few airlocks which is why the bleed pipe got inserted there at a later day.

I did leave the hot water on all night so all pipes got nice and hot, but this morning when I checked, the flow all the way to the cylinder is piping hot, the return is where it leaves the cylinder but then it goes cold at the junction with the cold feed and is cold down to the boiler. No magnetic attraction though so it may be blocked with something other than sludge.

Certainly worth investigating that bit once I've drained down, although it's in a real awkward spot. I'm guessing a plastic push fit 28mm x 28mm x 15mm tee would do the job if I cut out the old soldered tee, I normally use compression fittings but wouldn't have the space to get spanners in.

While I'm at it, I may replace the whole cold feed pipe from the tank with plastic push fit pipes in case there's blockages in that, it has several 90 degree turns.

 

[DP]

I would avoid plastic to be honest
Blockage more likely to be on the tee that connects to the feed/ expansion pipe to the cistern

 

[AGAS]

you wasn't using a fridge magnet was you

tee would do the job if I cut out the old soldered tee, I

sweat the old soldered joints off then you will have something easier to connect to

 

[chrisw99]

An update, I managed to clear the blockage last night, which was at the cold feed tee, confirmed because the last couple of days the return pipe was hot to that point then cold straight after. Also bleeding an upstairs radiator it just trickled out rather than spurting out as it used to, so not much pressure getting through from the tank

Cleared it by emptying my disgusting F&E tank via a jug and a bucket and giving it all a good clean, then connected a hose to the bleed point on the cold feed. Turned it on, and as expected the tank started to fill from the bottom. Held my thumb over that hole, which meant the only way the water could go would be via the blockage, up through the cylinder coil and out the F&E expansion vent. After a bit of gurgling some water trickled out then a few splurts of crap and then a proper gush.

Slight panic as I assumed it would just drain down the overflow but it didn't, must be a blockage in that, so managed to dash down the ladders and to the tap and turn the hose off just before the tank spilled over!

Ran the heating for an hour and now the return pipe got too hot to touch after the cold feed tee, so looks like I've cleared that and got it circulating again. The upstairs radiators bleed a lot better too. By coincidence, the letter from BG arrived yesterday confirming we had a blockage and we need a power flush, quoting £685. Hmm, a bit of hose, a jug and a bucket was all it needed.

The water that ended up in the F&E tank from the system was brown and disgusting, probably because of the Fernox F5 that's been in a week. I'll do a couple of drain and refills this weekend.

Whether it's fixed the boiler problem remains to be seen.

 

[Dan Robinson]

 

[chrisw99]

View attachment 121051

Exactly how I felt as I sat down with a well deserved beer!

Do you chaps think it's worth fitting a Magnaclean if I'm going to be draining down? As mentioned previously, the garage rebuild in 2-3 years time will involve replacing the boiler with a combi, getting rid of the HW tank and cylinder, and most of the garage pipework, but all the radiators will be staying the same so it's probably worth doing it now just to keep the dirt out of them?

 

[ianmcd]

yes I would fit one and you can always move it and reuse it on your new combi

 

[Donald_diy]

Would the power flush have cleared this type of blockage ?
Blocked cold feed I believe