Air getting into combi system

macman

Then simply change the bleed valve, Isolate the rad using both TRV and lockshield valve, undo the valve and replace with a new one. 2 minute job, much better than bodging about with a spanner.
The head may be alright but the bleed key rounded.

hubb

macman wrote: »

Then simply change the bleed valve, Isolate the rad using both TRV and lockshield valve, undo the valve and replace with a new one. 2 minute job, much better than bodging about with a spanner.
The head may be alright but the bleed key rounded.

Ok, will do. Doubt the key is worn as it works on other rads.

southcoastrgi

as mm said in #34 don't try to take the larger nut out the rad just undo & replace this bit

hubb

Ok, thanks. It looks like it has been sealed with paint but will have a go.

keystone

hubb wrote: »

To be honest, I would rather just sort it myself as he doesn't seem to know as much as initially I thought.

Not sure why you are letting him off the hook so easily. Actualy doing so is doing him a disservice (because he now thinks he can get away with it) and also his future customers. he has to learn.

I find plumbers very hard to trust. I can do DIY if I get instruction, I just need advise here first.

But you trust those of us on here that do this sort of thing for a living? Mmm - seems a bit of a contradiction in terms. Plenty of free advice on here of course.

If I get him back in under duress I don't want the situation turning uncomfortable.

Theres really no reason why it should. You've paid him to do a job. He should be professional about it not chucking his teddy in the corner.

Unfortunately I had no idea he should have balanced the system and put in inhibitor at the time.

There should have been no need to rebalance the system if all he did was drain it and fit the new valves. Even if he turned the LSVs off provided he noted their postion and opened them again to the exact same position there should be no real need to rebalance. If the system was drained then the inhibitor was drained as well so it needs replacing. There is no reason why you should have needed to know this unless he was keeping you fully informed as to what he was doing and why. There is EVERY reason for him to know it though.

Wish you well with it.

Cheers

Edit: Sorry - LSV = Lock Shield Valve on t'other end of rad.

hubb

Point taken and yes, thankyou all for your free help. I have bled the air out with the smaller nut and it worked a treat. Just a little more advice- It was coming out at a force when I heald a match to it. It caught a light like a blow torch. Not too fierce but it did ignite. I then did the filling of the glass test (as advised here) upside down twice with a match and there was no popping or even hint of any ignition. Perhaps it was just burning air. Does this sound ok ?

keystone

hubb wrote: »

Point taken and yes, thankyou all for your free help. I have bled the air out with the smaller nut and it worked a treat. Just a little more advice- It was coming out at a force when I heald a match to it. It caught a light like a blow torch. Not too fierce but it did ignite. I then did the filling of the glass test (as advised here) upside down twice with a match and there was no popping or even hint of any ignition. Perhaps it was just burning air. Does this sound ok ?

Hydrogen. Released from the system water by corrosion in the system. Its not as clean as you think (or have been told) it is I'm afraid.

Cheers

hubb

So do I put inhibitor in and it will stop ? Or take the rad off and flush it out perhaps ? So the gas has built up in such a small space of time from him fitting the TRV's. When the other clown who installed out boiler (long story) came back 5 months later to put the inhibitor in (yes, he didn't do it straight away either) that could have started it. They did do a high velocity flush though and they were a long time doing it, not a quick job.

keystone

Inhibitor won't deal with existing corrosion. Likewise a magnaclean (or similar device) is no real use on a dirty system but works fine when the system has been cleaned out first.

I think I'd be testing the system water in the very immediate future to see what's actually in it.

Cheers

Edit: Inevitably your corrosion will not just be in one single rad I'm afraid.

Myser

hubb wrote: »

So do I put inhibitor in and it will stop ? Or take the rad off and flush it out perhaps ? So the gas has built up in such a small space of time from him fitting the TRV's. When the other clown who installed out boiler (long story) came back 5 months later to put the inhibitor in (yes, he didn't do it straight away either) that could have started it. They did do a high velocity flush though and they were a long time doing it, not a quick job.

If you cannot find out from the chap whether inhibitor was added, drain the system down completely (from the main drain valve), add the appropriate amount of inhibitor for your system based on the number of radiators and then fill the system again with water from the filling loop.

That way you can be sure it's been done properly.

Testing the water is a good idea - some of the companies that produce central heating chemicals offer this service.