Do I need a header tank for a closed system?

[Deansplit]

I changed my cylinder from copper to pressurised (Santon) and want to make it a closed system as understand this is better. Does this mean I do away with the header tank? Is so, where doe it get its feed from?

 

[Agile]

This sounds like a potential time bomb!

You fill a pressurised system through a filling loop.

All unvented cylinders have to be installed by someone who is qualified and then notified to Building Control !

Was that done with yours?

Tony

 

[Deansplit]

I did it all myself - have a friend who does lots of plumbing although not an 'official' plumber - CORGI reg tho. I've replumbed 17 rads in my home so just thought I'd have a go. Been fine for 5 yrs!

 

[JPC]

been fine for 5 years.....why you asking now then ?

 

[Deansplit]

because I left the header tank in. But now we have the house apart to do an extension, so with system empty and scaffolding to the roof I thought it"s a good chance to close the sys, remove the overflow, replace tiles etc. I also need to fit a gauge.

 

[Agile]

And an expansion vessel if you want it to work!

Your unvented may be at risk of exploding, apart from not complying with building regulations if it was not notified.

Tony

 

[Deansplit]

expansion vessel was installed, that's why I presumed there was no risk of explosion?

 

[BournemouthPlumber]

On the basis that this is effectively a presurised bomb in your house I can't believe you would have your family in this vicinity without having it installed and signed off correctly! If this explodes it will remove the roof and half of your house.

You say you installed an expansion vessel. When was the last time this was checked and repressurised?

Absolute stupidity!

You should not be touching this if you are not registered and qualified!!

I assume that you have had it serviced every 12 months to ensure that all its safety features are working correctly!...

 

[MIGEM]

Water under pressure has a higher boiling point, so if all of your safety devices are not checked and fail, or you have a high temperature leak to atmosphere, you risk blowing yourself up.
Water expands 1,600 times when turned to steam.
If your cylinder flashed to steam, you stand to have the volume of 1,600 cylinders in your airing cupboard, within a fraction of a second; and they will not fit!

Also D1 and D2 considered?

and....

I did it all myself - have a friend who does lots of plumbing although not an 'official' plumber - CORGI reg tho.

What do you think CORGI reg means?

 

[tamz]

Watch this. Not saying it will, but it can happen.
Get it checked

http://www.metacafe.com/watch/261949/unvented_cylinder_explodes/

 

[BournemouthPlumber]

or this one:

http://www.youtube.com/watch?v=rGWmONHipVo&feature=related

Installation of these things is regulated for a reason. You wouldn't let a non gas safe engineer install a boiler - so why would you do the same with this.