Help!! Do I need to drain the system?

[Recovering Chippie]

Hi folks,

I am a chippie and not a plumber hence asking what is probably a daft question.

backstory I have a open vented heating system with an oil burner. My hot water stopped working and after a bit of investigation it seems that my tower MV2-22C zone valve has died. The micro switch lever arm has fallen off and obviously this means no switching of hot water. As a way of getting hot water In the meantime I have wedged the micro switch on and am using the fused spur to turn turn the boiler on and off as necessary to provide hot water as we don’t need heating at the moment.

there are 3 no of these 2 port valves in the system. 2 down next to the boiler for downstairs and upstairs heating zones and 1 valve for hot water located right next to the hot water cylinder next to the top entry of the heating coil.

I know the tower valves are not the best but I bought a new model VAL222MV as I assume it will be A simple swap job.

my question is- can I get away without draining down the system if I close all the Lockshields on the upstairs rads which are slightly higher than the zone valve?? My thinking is that would reduce the amount of head pressure...
also thought if I cap the breather pipe and bung the feeder tank outlet that would possibly let me swap it live without too much water escaping.

Would this work or do I just have to bite the bullet and drain or part drain the system??

I’d get heating engineer in but there aren’t many happy to breach lockdown here in N.I.

Any advice would be greatly appreciated.

Steven

 

[muggles]

You should be able to just replace the head, no plumbing required

 

[ianmcd]

no need to close the rad valves just bung the F&E tank as you said, you can buy a kit for doing it, years ago we used a carrot and a potato, you will still get some water coming out so have a large towel or basin under the valve , it will stop though

 

[BoilerBob]

The carrot and spud god that brings back memories of a life without complications. Bob

 

[Recovering Chippie]

Muggles,

sadly it is the old tower Jobby that the head can’t be changed on and the valve is sticky. Tried to loosen it off but it is also done for.

IanmcD,

thanks for the reply. I know the bung works for a cheeky rad valve change but wasn’t sure if it’d hold on the 22mm going into the coil.
I was gonna put a push for stop on the 15mm vent and invent something to bung the tank.
The bung kit might be worth a couple of quid. Any idea what they Call them?

Cheers

 

[ianmcd]

Muggles,

sadly it is the old tower Jobby that the head can’t be changed on and the valve is sticky. Tried to loosen it off but it is also done for.

IanmcD,

thanks for the reply. I know the bung works for a cheeky rad valve change but wasn’t sure if it’d hold on the 22mm going into the coil.
I was gonna put a push for stop on the 15mm vent and invent something to bung the tank.
The bung kit might be worth a couple of quid. Any idea what they Call them?

Cheers

https://www.ebay.co.uk/itm/REGIN-RE...707275&hash=item5b73f1dc09:g:JQ0AAOSwnm1eWePK

Basically you just have to make two stop ends and the water will be held in the vacuum, if you put a stop end on the expansion and you can find something to seal the outlet, then job done , that is all the bung kit does

 

[Recovering Chippie]

Cheers Ian.

I have the 15mm stop but will see if I can get one of those kits anywhere local as I don’t fancy Using a carrot unless I have to.

many thanks

 

[Recovering Chippie]

Just a follow up query....

My feed and expansion tank does not appear to have an expansion pipe....

Is it possible that the one pipe does feed and expansion or do I need to go digging through 400mm of insulation..??

 

[Recovering Chippie]

 

[Recovering Chippie]

Looks to me like a 22mm feed/exp teed of heating circulation pipe and a little air event pipe to aid filling etc...

Is that right??

 

[Recovering Chippie]

 

[Recovering Chippie]

Think I must have been right. Seemed logical enough so I went ahead and did the change over. Vacuum held perfectly which was lucky as even though I was replacing with the same make, the new one had a ever so slightly bigger thread. Had to cut off olives and do it properly.... using the new olives and nuts.

Thanks for the help fellas- much appreciated.