Inley working pressure advice needed

[mutley racers]

Hey chaps, well i have been so busy for the past month that I have not had time to come on the forum. Hope you are all as busy as I.

Any way, down to business

I have just installed a Vailliant 831 combi boiler. Working pressure at meter: 20mb
Working pressure at appliance:16mb

Manufacturers instructions say 16mb is ok.

is it?

The pipe run is 13metres 28mm and 2 meters 22mm, hardly any bends.

 

[SimonJohns]

It is because of the gas valve.

There is a technical bulletin about this very issue

 

[mutley racers]

where can I find this technical bulletin simon?

 

[SimonJohns]

I think it's been removed now sorry.

It was tb033

Best port of call is now going to be valiant

 

[RPG 80]

it's only a 1 MB drop to the appliance your loosing the rest on the gas vv if it gas rates and the emissions are in spec I'd be happy

Sent from my GT-I9100 using Tapatalk 2

 

[mutley racers]

ok, thanks guys. I shall give vailliant a call tomorrow and see what they say. The gas rate is spot on so am thinking that its all ok.

 

[mutley racers]

Can someone give me gas safes tele number? Or where to find it? As I can't seem to find it on their site. The technical side.

Cheers

 

[SimonJohns]

Just phone the normal number and ask to be put through

 

[mutley racers]

cheers

 

[jtsplumbing]

They will only tel you to refer to MI's !

 

[Bernie2]

Try Bulletin 189. But cannot make out exactly what you are asking? If you have 20mb at the meter and only 16mb at the appliance it seems more likely that the gas pipe is undersized, blocked or badly designed.

 

[breakdown]

working on worcester condensing boilers and there technical bulletin claims.
example 19mbar minimum operating pressure at meter.
pressure loss across pipework 1mbar.
pressure at appliance isolation valve 18mbar.
pressure at appliance test point with 1.5mbar lost through appliance controls 16.5mbar.
so they allow 2.5mbar from meter op to boiler test point op.
hope this helps.

 

[Bernie2]

If the appliance inlet pressure where it is usual to test from, is 19mb dynamic then the pipework should be okay. Where are you testing from? The gas valve may well be droppng the pressure as breakdown says.