Cold Radiators

[morpheus83uk]

Ah right well the wet and dry vac I have has a blower on it so I may try blowing it and sucking it to see if it shifts it.

Ah tight so push it with water directly connected to the hose?

Thanks

James

 

[morpheus83uk]

Ok quick update on this. I have drained the system today which turned out a lovely yellow color and have flushed it out twice and everything now runs clear.

When comparing the flow and return pressures the return seems fine as it comes out at a good rate however the flow was just dribbling. So we took the wet and dry vac to the pipe and left it going for around 15 minutes and it sucked out some lovely black colored water so there is some form of blockage in that pipe somewhere but the cleaner has also cleaned out quite a lot too. So we put some more water into the system and then sucked it out again and more came out and the flow increased not as much as the return but it was flowing more than a dribble. Given the time we have now stopped and connected everything back up and filled the system back up and bled the radiators so see what happens now. If the problem persists then we will continue to use the vacuum on the pipe and we think we found where its coming from so may also be able to blow throw it to see if we can clear it that way but either way we have removed quite a lot of rubbish from the system.

Also could it be that the Flow and return are on the wrong way around? and would swapping them cause any issues?

I will keep you updated on what tonight / tomorrow brings.

Thanks

James

 

[John D v2.0]

Might help if you tap the pipe while flushing it.
Water from the mains at 3 bar or so will be higher pressure than a vac at less than 1 bar so would clear it better. But both together would be even better.

 

[morpheus83uk]

Thanks we did try it at 1.5 bar so I may increase it to 3 and have the hose at the ready and get them both on it which should hopefully clear the pipe.

 

[dilalio]

The other thing you can try is a tyre valve (schrader valve) which you can connect to a 15mm straight coupling compression fitting. The other end of the compression straight goes onto your pipework... you can then use air (up to very high pressure) to force the blockage back up the pipe, using a foot pump.

 

[morpheus83uk]

Thanks so in essence push from the previous radiator towards the problematic one into say a bucket? Or the other way towards the good radiator?

Thanks

James

 

[John D v2.0]

Whatever you do don't have anyone too close to the outlet when you're pumping.
1000cc(say) of air at 5bar has a huge huge amount of energy compared with 1m3 of water at the same pressure. That's why ufh pressure testing only uses air for a low pressure and after that it has to be water for safety reasons.

 

[morpheus83uk]

Will do it will be going directly into a bucket to catch everything and covered to prevent splashback.

 

[John D v2.0]

Will do it will be going directly into a bucket to catch everything and covered to prevent splashback.

Put it another way, if you compress an original 0.1m3 of air into 20l of your pipework to 5 bar/75psi, that would have 7kj stored. Release that suddenly during 0.1 second and you have an average power output of 70kw! There's a reason they use compressed air to launch heavy rollercoasters. Ever watched bottle rockets on YouTube? They have much less air in them.
Your bucket isn't going to stand a chance if everything goes wrong IE no leakage then sudden release at high pressure from a relatively large reservoir of air.
Reach the same pressure with water which is virtually incompressible and there would be almost no energy. So if you can pump mostly water it'll be better
All I'm saying is if it's stuck and not leaking out, don't keep pumping. But it'll take you a while maybe a few minutes to put that much energy into the system.

 

[morpheus83uk]

Ok no worries so I am just pushing it into the system then and flushing the system to get it out I presume? I will give the water a go first since that's what I have already done and then maybe go for the air.

If I understand about pumping mostly water fill the system and them pump in air so that the water will be pushing the blockage and when it comes into a bucket it will be OK?

Thanks

James

 

[dilalio]

You can lead a horse to water, but a pencil must be lead

 

[dilalio]

 

[morpheus83uk]

Yes that video helps alot I now get what you mean.

I will see what I have in the garage or if I have to pick something up.

Thanks

James

 

[dilalio]

Ok no worries so I am just pushing it into the system then and flushing the system to get it out I presume? I will give the water a go first since that's what I have already done and then maybe go for the air.

If I understand about pumping mostly water fill the system and them pump in air so that the water will be pushing the blockage and when it comes into a bucket it will be OK?

Thanks

James

Exactly... you’ll only be pushing the air into the system pipework! The idea is that it should push any blockage upstream of the bottleneck where it accumulated... that action should help it break down and disperse.

Tom’s videos explain it all - he’s got plenty more on his YouTube channel and I love ‘em

 

[morpheus83uk]

Brilliant thanks Yeah i now understand what the goal is I just couldn't get my head around it before but the video explained it well.

Thanks again I will be doing this on Monday so hopefully it will get sorted.

Thanks

James