How to remove a TRV/ Lockshield valve without bleeding whole system
- Thread starter ukjules
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Quick or slow. Your choice.
On a Baxi 800 you should be able to safely close the flow and return valves. Then you do as Denso says, crack the joint, wait till the water stops and change the valve. I wouldn't even bother turning off other rads.
Ok.
Letting water out of the rad is never an issue.
Assume it's drained. Valve off loose. Valve only held on 15mm pipe but turned off to stop water flow. Water has stopped from the rad.
All other rads valves off - still don't know if that's necessary. ?
So now I have a valve only holding water back on 15mm pipe. Yes I now want to change it but your sequence says
"crack the joint, wait till the water stops and change the valve."
I Def don't want to wait till all the water stops after cracking the final joint as that is draining the system !! I don't want to do that as per title of thread.
The question is can I take off valve and quickly (why in god's name would you not want to stop water quick) swap valve for new one.
I think you say by turning levers on boiler will minimise this issue.
And
Other person (can't go back to see name) says simply turn back in valve and see if it's possible. If so do it.
I am an IT consultant and deal with sequence .... Sorry about that but to do this job that is easy to you I have to have the sequence ...
Letting water out of the rad is never an issue.
Assume it's drained. Valve off loose. Valve only held on 15mm pipe but turned off to stop water flow. Water has stopped from the rad.
All other rads valves off - still don't know if that's necessary. ?
So now I have a valve only holding water back on 15mm pipe. Yes I now want to change it but your sequence says
"crack the joint, wait till the water stops and change the valve."
I Def don't want to wait till all the water stops after cracking the final joint as that is draining the system !! I don't want to do that as per title of thread.
The question is can I take off valve and quickly (why in god's name would you not want to stop water quick) swap valve for new one.
I think you say by turning levers on boiler will minimise this issue.
And
Other person (can't go back to see name) says simply turn back in valve and see if it's possible. If so do it.
I am an IT consultant and deal with sequence .... Sorry about that but to do this job that is easy to you I have to have the sequence ...
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Open the valve and let in run into a bucket!!!
No, it isn't. You might get some water from a bit of pipework, nothing more.
I've said all this several times now.
If I want my computer fixed I pay someone who knows what they are doing.
A pro could change your rad valve in 10 mins and spill no water. They would charge you for an hour but probably worth it.
Close flow and return valves on boiler.
Open bleed vent on radiator and catch water in cup or with towel.
When water stops close vent, put old towel under valve to be removed.
Loosen nuts on either side of valve.
Remove valve and replace with new.
Tighten nuts
Open flow and return valves
Check for leaks
Repressurise as required
Open the valve and let it run into a bucket.
I think this means let it run into a bucket while you swap over the valves, not to drain the system.
As for Elkato
A pro wanted to charge me 500£ to remove flush and put back rad , re pressurise and add inhibitor into the mag filter.
I did it for 11£ using a sequential method. All done in 1 hour perfectly with help from here and good preparation.
I class a valve removal the simplest of tasks after doing that and all I wanted to know was how to do it without draining the system.
A simple sequence of events that need to be done in order. I told you the status and wanted to know the situation when taking the valve off the pipe exposing a live water pipe.
Whatever. I will do as Denso says but with a 15mm stopper just in case.
I think this means let it run into a bucket while you swap over the valves, not to drain the system.
As for Elkato
A pro wanted to charge me 500£ to remove flush and put back rad , re pressurise and add inhibitor into the mag filter.
I did it for 11£ using a sequential method. All done in 1 hour perfectly with help from here and good preparation.
I class a valve removal the simplest of tasks after doing that and all I wanted to know was how to do it without draining the system.
A simple sequence of events that need to be done in order. I told you the status and wanted to know the situation when taking the valve off the pipe exposing a live water pipe.
Whatever. I will do as Denso says but with a 15mm stopper just in case.
You also got to understand that we know what to do after years of training and experience and we come on these forums and give our time and knowledge free of charge. Good luck with the job and remember, its just physics. If you can remove the pressure and stop air getting into the system then water can't get out.
More haste less speed!
The important point, you seem to be not seeing, is that if air cannot get in, the water will not come out. As has been explained to you, a small amount of water will come out, but only until a vacuum has been formed, above the column of water in the pipework.
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I got the carpet washer ready, I knew under the carpet there were quarry tiles, did the job as fast as I could and water did not spread over on foot, and was quickly sucked up with carpet washer, as @Harry Bloomfield says, if air can not enter only lose water until pressure drops to zero. This was late mothers house, with a sealed system.
This house, very different, floor made of a board which will lose strength if it gets wet, and the system uses a header tank, so no real options either drain down or freeze. There may be an isolator on the header tank, I have not looked.
This house, very different, floor made of a board which will lose strength if it gets wet, and the system uses a header tank, so no real options either drain down or freeze. There may be an isolator on the header tank, I have not looked.
A fluid is incompressible, and cannot be 'stretched'. A gas (air) can be compressed, or 'stretched' - which means if you prevent air getting in, or make sure there is no air already in the water column, the water in the column cannot escape.
Liquid.
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