ventilation requirements for conventional flue gas boiler

[smmjh11]

Recently our club had its yearly boiler service and the engineer stated that we needed more ventilation but he did not state what we required .We have an ideal concord C series 2 gas boiler but the identification badge seems to of come off so I cannot say what the BTU's are.It is a convential flue type in a commercial building and is located in the basement thanks

 

[kevplumb]

to be on the safe side knock a hole in the wall 2m2

 

[ollski]

I've found over 50 variations on the concord conventional flue boilers....any more identifying numbers / letters on it?

 

[doitall]

High Level= 270cm² plus 2.25 cm² per kw in excess of 60kw total rated input.

Low level= 540cm² plus 4.5 cm² per kw in excess of 60kw total rated input.

 

[PEDANTICVINDICTIVEMAN]

Have we gone back to 4.5 Cm2 per Kw or have you got it wrong doitall as I thought it was 5Cm2 per Kw

 

[ollski]

Have we gone back to 4.5 Cm2 per Kw or have you got it wrong doitall as I thought it was 5Cm2 per Kw

5cm2 per kw net, 4.5cm2 per kw gross

Why the high and low vents? have you seen this compartment its in DIA??

 

[doitall]

4.5cm² is based on the appliance Gross maximum rated heat input

whereas;

5cm² is based on the net maximum input.

Perhaps I should say these are Minimum requirements direct to outside air, from a room you would double the sizes.

My figures are also per manufacturers instructions pvcman

 

[PEDANTICVINDICTIVEMAN]

Yea but I thought we were supposed to be working out everything in net and manufacterers were supposed to badge in net now, but if you came across an old boiler badged in gross you would convert gross to net by didviding by 1.11 then calculate 5cm2 per Kw.

 

[ollski]

works out the same

 

[PEDANTICVINDICTIVEMAN]

This is a bit like lpg not needing extra ventilation as it's hotter so not on for as long, thing is what happens if the stat or gas valve sticks then it aint gonna shut off and it aint technically going to get enough oxygen.

 

[doitall]

Yea but I thought we were supposed to be working out everything in net and manufacterers were supposed to badge in net now, but if you came across an old boiler badged in gross you would convert gross to net by didviding by 1.11 then calculate 5cm2 per Kw.

No I wouldn't

I would look in the manufacturers book, much easier

 

[PEDANTICVINDICTIVEMAN]

So would I, just being pedantic

 

[doitall]

So would I, just being pedantic

About time you got all pedatic over at Argi.org

 

[PEDANTICVINDICTIVEMAN]

Cant be arsed, can only just be arsed to bother with this site.

 

[ChrisR]

smmjh11
If you can't find the power of your boiler , go watch the gas meter when it's on full (and nothing else is)
If you have a metric meter time how much gas is used in 2 minutes, if it's an imperial one, time how ,long it takes for one cu ft, that's usually 1 revolution of the dial with the pointer. T
hen tell us if the boiler is in a compartment, if so where the fresh air vents would go; ie into a room or straight to outside.

Edit: PVM is right (next post). You can get a minimum figure from the above, but the boiler might have been "turned down" by the installer, in which case the vent has to be big enough to suit the boiler when fully on.