Putting ball valve in feed pipe from tank on an open vented system.

[ringi]

While I have my system drained down I am thinking of putting a full bore ball value in the feed pipe from the tank.

This would make it easy to sort out any future problems, as it will be easy to just turn it off and cap the feed pipe to sort out most single joint issues.

Am I thinking along the right lines?

Why is this not done as part of a standard system?

 

[SimonJohns]

It's a saftey issue if you do this

I would NOT reccomend doing this

 

[erpkid]

Only consider this if there is a separate 22 mm or larger vent pipe ( the usual situation ). I have seen systems where the feed also functioned as the expansion, very bad practice, so if you valve one of these up and accidentally close it you have made a bomb

 

[ringi]

There is a separate 22 mm vent pipe! Having tanks that can freeze in my loft is bad enough, yet alone a bomb.

 

[erpkid]

:yes: tends not to be the tanks it is usually pipes on dead legs etc. Also as the temperature drops watch out for dripping overflow caused by ballcocks letting by. If the drip and wind chill work together you will either have a spectacular icicle or a blocked pipe and the soggy ceiling. I always fit a full bore lever valve on the rising main to the loft as this is quicker than getting the loft ladder down in an emergency and easier for customers as gate valves tend to be stiff and after a few years ineffective

 

[kirkgas]

Back to basics gentlemen, the pipe from the bottom of the tank is the feed & expansion pipe, do that under normal operation the heated/expanded water goes up the pipe where it is accommodated in the tank, therefore do not put any valve on the pipe which if closed will cause the system to malfunction
PS I will add the next bit cause if I don't someone will say the water will go up the cent pipe as that's what it's for
The vent pipe is to allow excessively heated water to escape into the tank safely and quickly, ( so its only used under fault conditions) not as part of the normal design


Sent from my iPhone using Tapatalk

 

[ringi]

:yes: tends not to be the tanks it is usually pipes on dead legs etc. Also as the temperature drops watch out for dripping overflow caused by ballcocks letting by. If the drip and wind chill work together you will either have a spectacular icicle or a blocked pipe and the soggy ceiling. I always fit a full bore lever valve on the rising main to the loft as this is quicker than getting the loft ladder down in an emergency and easier for customers as gate valves tend to be stiff and after a few years ineffective

I have insulated all the pipes well and they are under the loft insulation apart from the hot water tank and the header tanks that are high up in the loft, so don’t even get heat from the ceiling below. I have put as much insulation on them as I can.

I like the ideal of a full bore lever valve on the rising main!