isolation valves?

[secret squirrel]

Yet again I find myself puzzeled, it seems to happen daily. Most of the time I can work things out but every now and again........

I have done a couple of jobs recently and whilst poking around the airing cupboard (I do this every job so I can work out whats going on and see what others have done) I have seen isolation valves on the flow and return out of the HWC.

WHY?

My thinking for this is to assist in creating vacuums for changing valves etc.

However, I was taught that the least valves you have for a customer to turn on and off the better.

The first one I saw was in a sheltered housing complex and the 2nd was in a 3 bedroom house.

Is there another reason or is the vacuum idea correct? is this good practise?

 

[Bernie2]

No it's not good practice its adding frictional head loss to the system. But I can think of a few reason why they are on. If they are old buildings perhaps they have had the cylinder changed yet wanted to keep the heating on.

If they are new perhaps they have had the heating on and did not want to install a big shiny copper cylinder to soon. The price of scrap is good now days.

Some systems balance the cylinder primary supplies. Often if you leave them open, they pinch water off the heating circuit. It all depends what sort of system it is.

As you know, no two ways of doing the same thing seem to be often found in Plumbing, its what makes it so interesting but complicated.

 

[secret squirrel]

Would it be good practise to remove the valves?

Or

Best just to leave them as they're not causing a problem?

Thanks

 

[Bernie2]

I would leave them if they are not causing a problem. If your a bit concerned and they are gate valves with their hand turn wheels still on. Remove the wheels and give them to the person in charge.

At least you then know, nobody can fiddle with the valve accidentally, only if they do it on purpose by either getting and using the wheels or using a tool to open or close the valves.

That way, you could probably say you had taken reasonable action to allay some of your concerns. After all a valve can do little harm unless you close it, and bottle the water up, making it perhaps have to expand to get out causing a possible explosion.

Good Fortune

 

[bobpape]

It is normal to remove the valve wheels which is a good indicator that they are there
for a special purpose and not to be messed with

 

[stevetheplumber]

funny i was always told fit as many valves as you can get paid for chance are your going to be working on the system in the future and makes life easy same goes for drain offs

 

[david williams]

allways fit valves on primary pipework ,in kent hot water cylinder will only last 6 to 10 years it may be you who has to replace cylinder,i allways tell client where all valves are leave a list to show what they do ,and tell them to close and open them a lest once every six months that way they will work when you need them to,[except locksheilds ] or offer your client yearly maintenance inspection.