Safety valve -which?

[Malc]

I'm replacing a coal fired system with oil. The new oil boiler will have usually vent pipe rising to over the header tank (system will be vented type). As well I plan to put in a safety valve near the boiler (to blow off if the vent is blocked). On the BES web site there are 2 valves which look suitable, 7512 and 7513. Are these the correct ones? Also, as the boiler pipe will be 22mm should I use 3/4" or would 1/2" suffice. 1/2" would be smaller and neater but would it be suitable?

Opinions?

 

[Kingsway]

you dont need a safety valve on an oil fired boiler.
a 22mm vent will be ample and unlikely to block.
Solid fuel appliances used safety valves because u had no control over the heat build up and some had 15mm vents.
With modern boilers you have safety devices like thermostats, high limit stats and larger vents to accomodate any problem,

i have been fitting oil fired boilers for 12 years and have yet to fit a safety valve
hope this helps