Mains pressure systems

[Roundthebend]

I'm replacing a graverty system, having a new system boiler fitted.
I have just found out that there are two types, vented and unvented. That the unvented has to have an yearly inspection, which will have to be paided for.
Which is the best system, my builders plumber is not much help.
Sorry i'm rushing this got to go to work.

 

[secret squirrel]

Unvented, much better pressure to hot tap,

 

[Puddle]

The pressure to your taps will stay the same
The vented is probably the same as you have now with a small header tank in roof space,to fill system and keep it topped up,it has a open vent over the small tank to allow for any expansion in system
The unvented boiler does the same job,but the small header tank is removed and capped off, along with the open vent pipe,making the system completely sealed,due to this it has a expansion vessel in boiler to take care of system expansion when heated and as you do not have a tank to fill system it also has a pressure gauge and pressure release valve for safety ,also a filling point is fitted to allow system to be filled up from mains pressure to 1 bar,also circulating pump will be supplied and fitted in boiler,this is why they are more expensive to purchase
As far as first year service ,most boilers require this if cover over one year to validate cover after this time
Which is best,I would say unvented system but both will work well
Would add if you are replacing gravity system,maybe also look at replacing cylinder ,for better recovery time and efficiency

 

[fuzzy]

a system boiler is a sealed heating system, this can run with either a graity or sealed hot water system known as unvented. just check your taking of hot water when you say unvented and not unvented refering to the heating system

 

[secret squirrel]

a system boiler is a sealed heating system, this can run with either a graity or sealed hot water system known as unvented. just check your taking of hot water when you say unvented and not unvented refering to the heating system

I automatically presumed we were discussing hot water not the central heating......

 

[fuzzy]

I automatically presumed we were discussing hot water not the central heating......

I know you did, thats why i thought id just check as some people get mixed up wiith the terminolgy. If we give advice on the hot water system and he is on about the central heating because he used the word unvented instead of sealed we will be barking up the wrong tree!!!!

 

[Roundthebend]

Thanks for all your replies.
I am looking at a fully pumped system, with an unvented hot water system.
Besides the annual boiler service will the system require a further inspection due to the pressurised hot water system?

 

[wnjswozo]

yes,they would check unvented cly,at same time