450mm offset from storage vessel

[tom keane]

I have read the r.d treloar second edition book and it says that there should be a dog leg of 450mm from storage vessel on (page 86-87).

But I have also bought a lot of other diy and pluming books and all of them say that there should be a staight vent pipe from the top of the vessel to the tank wich way is the correct way to do this and why.

also I know that there were change in the building regs in april please can some one explane what the changes are in plain english please

 

[Bahco]

First is right.
Vent pipe should come off the cylinder 450 mm horizontally and then rise up vertically to prevent parasitic circulation

 

[Slugbabydotcom]

also I know that there were change in the building regs in april please can some one explane what the changes are in plain english please

Here
are the building regs that changed and I would say that they were plain English. Have a click around the site and you may find concise versions.

Briefly it relates to energy efficiency. All/most new boilers fitted must be condensing. Systems must have controls so as not to waste energy etc.