open vented systems without a feed and expansion tank.

[jimbo639]

Hi, I would like information on open vented systems which do not have a feed and expansion tank and have a small cylinder approx a foot high and 8 inches dia,often situated above the hot water cylinder.This small cylinder has three pipes attached and a float type automatic air release valve, one of the pipes appears to be a feed from the cold water storage tank in the attic.It's function appears to be topping up the heating system automatically.Any replies greatly appreciated.

 

[danielp]

picture

 

[jimbo639]

Danielp,I will go back to the customer and take a picture next week.I am going to replace the boiler and they want to keep the existing system so I want to fully understand it.

 

[Mike Jackson]

I think it's some sort of variation on the primatic single feed cylinder system. Saves having a separate F&E cistern. Problem is it relies on an air gap to keep the two systems separate so you can't add any chemicals to the heating system.

 

[flat pack]

sounds like a servowarm company design.

what the name of the old boiler and age.
lots of these were put in the airing cuboard

 

[Bernie2]

Hmm

Sounds lika an old servowarm job. On some of their systems they used what they call a top up bottle instead of an F and E cistern.

 

[flat pack]

You also may find the pipe work may be silver colour.
this is crap pipe they used .
if you work on this it will cause you problems .
1/ fall apart in bits.
2/ or leak from pin holes.
3/ don't put any chems in the system you could be call back with leaks
uplifting floor boards etc.
4/ check it and pre warn your clients
5/ there a echo in the room

 

[jimbo639]

I think I have managed to attach a photo called 000_0203.jpg in attachments. Let me know if it has not worked!

Jim

 

[jimbo639]

Here is the over all photo.

Jim

 

[Mike Jackson]

Definitely an adaptor turning it into a variation on the single feed indirect system.

Mike