cold water combination valve replacement - megaflow

[fairylights]

This has been leaking badly and needs replacing...I have bought the part and a heating engineer came to give me a quote today, but he says it will take him 2hrs to replace as he has to drain the water cylinder completely by attaching a hose to it? I thought it was going to be a fairly simple job, being just a case of turning off the water by the black lever to isolate the cold flow and replacing the valve...(only what i have read online).

I would be grateful if someone could advise me how long a job this would be, as i have already had huge problems with this system since i moved into the house end of last year. Had two engineers who have taken £800 off me so far for the amount of work, so really looking to make sure this quote/explanation of work needed by a different engineer, is true. Does the cylinder/tank need draining?

Also, the pressure has dropped considerably again but he tells me that s because there must be a leak somewhere in the pipework..? I live in a Victorian house and obviously the central heating was a late addition, so all of the pipes to rads are above the floor...no leaks! I did have to bleed a rad yest, so could that be the reason for pressure drop?

Thanks

 

[fairylights]

Oh dear. Lots of issues there.

You should be able to change that valve without draining the cylinder.

Sorry, i dont understand anything to do with this system...lots of issues where please?

If there are so many issues...bearing in mind this system was fitted over 12+ years ago...looked at by numerous qualified engineers, i find it strange that all of a sudden i am being told on here that its got so many issues ....

Are you telling me that its unsafe?

 

[Howsie]

It does not conform to the required standards and yes I would say its unsafe.

For example, if your temperature pressure relief valve discharges I am confident that you'll get very hot water coming out of your tundish. If it was fitted correctly you wouldn't.

That being said I've seen worse.

 

[chris watkins]

What is unsafe ? If you are asking will it blow up then NO. Is it correct as per the manufacturers guidelines / instructions & the requirements of the building regulations then the answer is also no. Could the way it is at present cause problems & if the safety valves discharge then the answer to that is yes.
As ever there are a lot of people out there who do not know what they are doing & very little check to ensure it is done correctly (don't forget anybody can call themselves a plumber).
If you wish to Private message me an email address, I have put some text onto one of your photos (the file size is too large to post on here) to explain what we have been talking about.

Once again not dangerous but wants looking at by some one who knows.

 

[tamz]

^^ I agree. Keep things in perspective and don't scaremonger but a couple of things need looking at which any decent qualified guy will highlight.

 

[lbp plg & htg]

What is unsafe ? If you are asking will it blow up then NO. Is it correct as per the manufacturers guidelines / instructions & the requirements of the building regulations then the answer is also no. Could the way it is at present cause problems & if the safety valves discharge then the answer to that is yes.
As ever there are a lot of people out there who do not know what they are doing & very little check to ensure it is done correctly (don't forget anybody can call themselves a plumber).
If you wish to Private message me an email address, I have put some text onto one of your photos (the file size ir=s too large to post on here) to explain what we have beed talking about.

Once again not dangerous but wants looking at by some one who knows.

Not much is dangerous - but thats till something goes wrong then everything thats wrong could be dangerous.

Just pointing out the obvious, from the pictures, as a duty of care.