Manifold conumdrum

[roger smith]

Half of the rads on my 10 rad system are not working and I've turned the system off prior to draining and flushing the 10mm plastic pipes. For the first time ever I have just looked closely the the 28mm manifolds and got very confused !
The are two, red painted, brass 28mm manifolds with 12 ports (4 ports on 3 sides) on each. They are connected together with a T piece. The T piece goes to the Return and the outer ends of the two manifolds go to the FLow from the boiler.
At first sight I couldn't see how it work UNLESS the manifolds have an internal blanking off plate, making each one a 2 x 6 port. Such labelling as there is, appears to conform to that.
But I can find no confirmation from current ads or images on the net that such manifolds exist. So, are there, were there ever, split, single block manifolds out there that explain this ? Thanks..

 

[roger smith]

To make it clear what I'm asking..here's sketch of what I suspect (or hope it's like)

Manifold

• roger smith
• 3 Oct 2019
• 2

 

[Nige F]

Your sketch is accurate - such manifolds did exist and are still working . Do the small pipes have compression connections , it looks like they do from your drawing . That was usual too

 

[Terrywookfit]

One side flow and t'other return .

 

[roger smith]

@nigel & Terry..Thanks for the confirmation. At one stage I started top believe it had been installed by an idi00t and was working out how to rip it all out..It was probably installed 20 years ago and is the first time I've ever had a microbore system and knew nothing much about manifolds. I guess this type is no longer made....and yes they are all compression fitting on the ports (several are leaking, another headache)...So I'm back to checking all the 10mm pipes are clear.. Thanks.

 

[Nige F]

Come back if you can't clear the 10mm pipes - I did one by connecting individual pipes to the mains - then the rad end out a window - not for the faint hearted , but it was my son's house

 

[roger smith]

In 50 odd years of being a householder I've installed three CH systems using the 2 pipe (15mm) system. All worked perfectly and never gave any trouble. This 10mm plastic pipe scheme looks so scrappy - and inaccessible where the 1st floor is chipboard and the drops are plastered into the walls..
Anyway..I've enlisted the help of my B-in-law who was a refrigeration engineer and is good with pipes. We've dreamed up a scheme along the lines you suggested which will involve (next week) pressurising the system with the cold water make-up supply and, one by one, flushing thru each pipe with hose adapters on the rad valve. Any suspect pipe my be disconnected at the manifold and dealt wiith separately with full mains pressure. We well keep the pressure down to <4 bar in the first instance. I'm also going to dismount each rad and flush it outside with a pressure washer jet..Does that sound like a reasonable plan ?

 

[Terrywookfit]

If you have any totally blocked pipes, connect each pipe to a foot pump and try that.
It makes far less mess if something blows, as you have only got the pipe contents.

 

[bernardgreen]

It makes far less mess if something blows, as you have only got the pipe contents.

Using compressed air to blow a stubborn blockage out off a pipe can result in a projectile coming out of the pipe at high velocity. Like an air pistol this can cause injury if it hits someone

 

[roger smith]

Good points ! I'll prepare an air adapter just in case it's needed for a possible second phase but the other end will still be on the hose to catch a burst of pipe contents - and possible projectiles Thanks..I'll let you know next week how it all went !
edit: I've also bought 2 meters of clear poly hose to start the hose run, so I'll always know what's coming out...

 

[Terrywookfit]

Using compressed air to blow a stubborn blockage out off a pipe can result in a projectile coming out of the pipe at high velocity. Like an air pistol this can cause injury if it hits someone

Who the fook is going to stand in front of the pipe.??

The pipe will still have water in it so an explosive decompression will not occur....This is why pipework is tested hydrostatically !!