New rads fitted 4 weeks later one needing bled

[Robert Anderson]

Also if it was gasses how long would it take them to build up again so how long roughly would the rad need bled again you talking weeks or months I’m not sure I want to continually spend the winter touching radiators lol

 

[Chuck]

Ok thanks everyone seems a bit more complex than I had hoped I was hoping it may just be air from refil??

It probably is just residual air. It could also be hydrogen from the new radiators/pipework forming a 'passivating layer'. As long as you are sure some inhibitor was added when the system was refilled you shouldn't worry at this point. Just touch the radiator where the air/hydrogen is collecting once a week and bleed it if it's cold along the top. It will probably slow down after a week and have stopped completely after six months.

5 seconds of ffffffsssssing through pinhole bleed-point is a tiny amount of gas. Nothing to worry about.

 

[Robert Anderson]

Perfect thanks it’s just a hassle I don’t really need as most folk don’t lol and I get a bit ocd with this type of thing so I appreciate everyone’s help and reassurance my mates/neighbour is a heating engineer has been for a while he fitted the rads n said last night it would just be settlement air as we had to refil couple of times to get the repair done which was a olive at a jaunty angle lol anyway just thought I would ask the forum too and as always very helpful cheers guys have a great day

 

[Riley]

Next time you bleed, check to see if the gas coming out will burn.

Really wouldn’t suggest trying this as it’s dangerous

 

[Robert Anderson]

Yeh I’m not sure I want to start fires from gasses in my house to be honest unless it’s my hob

 

[fixitflav]

This test needs two separate samples of water in sealed containers. One from the heating system and one from the kitchen tap to act as a control.

What does the control prove? If the rad water shows no rust on the test, it's OK, if it shows rust, need to add inhibitor. Whatever the tap water test does.

 

[fixitflav]

Yeh I’m not sure I want to start fires from gasses in my house to be honest unless it’s my hob

Please yourself, but it's not exactly a Wehrmacht WW2 flamethrower! I've done it a few times. It's only a flame about 20mm long. You could let it burn until water starts coming out, when it will go out, or put your thumb over it to put it out. Obviously you'll make sure there are no curtains etc hanging near, or you might set them alight with your match, irrespective of any burning gas!

 

[Robert Anderson]

Ok cheers for all your help

 

[Chuck]

What does the control prove? If the rad water shows no rust on the test, it's OK, if it shows rust, need to add inhibitor. Whatever the tap water test does.

It's to show that the nail has been in the water long enough for a noticeable amount of corrosion to occur in untreated water.

Strictly speaking, one should drive the nail through a couple of cm of copper pipe and use that that as the test sample.

 

[fixitflav]

It's to show that the nail has been in the water long enough for a noticeable amount of corrosion to occur in untreated water.

Strictly speaking, one should drive the nail through a couple of cm of copper pipe and use that that as the test sample.

OK fair enough, knowing how long the tap water sample takes to go rusty gives useful information. If the rad water test is OK at that point I would put it to one side and check it every week or so for several weeks, to make sure.