spillage test and undersized pipes

[buckley plumb]

hi has anyone any tips on spillage testing fires - been to a few especialy regent radiant fires where the test has to be done between the 2 radiants the problem being the heat seems to melt the match further down causing a wide band of smoke giving false test.i have even put in smoke match tube and still struggle on some the heat effects the test.

also as i under stand low working pressure is ok as long as the burner pressure is achivable ,the gas instillation can be classed as ntc on existing installations.
what if you can get the burner pressure but not the min gas rate is this still ntc .a fire today was 19mb working pressure and 18.5 when boiler was on but it was a 6.9Kw fire and i was getting about 5.7kw only but burner pressure was ok this is when i wonder what to do.


thanks ant

 

[Reg Man]

Sounds like you may have a restrictive pipe. Working pressure at the gas meter with appliances turned on should read between 19 and 23 mbar's. Working pressure on the inlet to the appliance should be not less than 1mbar difference. (21mbar at meter 20mbar at appliance) If you have not got this; it shows that the gas installation pipe is to small or there is a restriction.

 

[GrahamM]

hi has anyone any tips on spillage testing fires - been to a few especialy regent radiant fires where the test has to be done between the 2 radiants the problem being the heat seems to melt the match further down causing a wide band of smoke giving false test.i have even put in smoke match tube and still struggle on some the heat effects the test.

also as i under stand low working pressure is ok as long as the burner pressure is achivable ,the gas instillation can be classed as ntc on existing installations.
what if you can get the burner pressure but not the min gas rate is this still ntc .a fire today was 19mb working pressure and 18.5 when boiler was on but it was a 6.9Kw fire and i was getting about 5.7kw only but burner pressure was ok this is when i wonder what to do.


thanks ant

I do not recall having an issue taking the spillage on these fires. Not seen one recently though. Are you using a smoke match holder and placing it in under the canopy just above the radiants?
Normally if you were getting just bellow the min working pressure, but still achieving the min burner pressure or gas rate and flame picture etc. is ok the appliance would have been installed NCS.
If you are taking a gas rate there is an unwritten rule of some tolerance for calculation error. I usually work to 5% or so. 10% and it is way off.

Did you give the injectors a look? A dirty or incorrectly sized injector can throw your gas rate off by some margin.

If you are still not getting the minimum or as near as, then you might have to consider elevating your classification to AR/ID as appropriate and recommend the supply is re-piped.

 

[buckley plumb]

hi graham i have been doing spillage test with match holder between radiants level with canopy 5mm in.when i push the holder above the radiants it pulls the smoke match ,is this ok as its not as the instructions say.

am i correct in thinking that f the working pressure is ok say 20mb but gas rate was down it could as you say be a fire problem .but if working pressure and gas rate is down then its more than likely to be the pipework undersized.

both fires i have had low gas rates on are kinder oasis and kinder kf100 wether this is just a coinsadent

thanks for the advise i used to work for a company doing new builds and maintenance but now working for myself and i am amazed what issues are out there .


thanks ant

 

[GrahamM]

There are a number of slightly different regent radiants ant, but here is a link for one. Shows the spillage test clearly.
regent

If you have the gas supply and Gas rate is down, it is an issue with fire. ie injectors blocked.(or maybe your arithmetic is a bit rusty)
If you don't have the gas supply that MI's are looking for it is an install issue or maybe working pressure at meter needs adjusted slightly. (21 +/-2 mbar)

Don't think I have came across any of they Kinder's other than the egg's.

 

[Billy Bob Bob]

hi graham i have been doing spillage test with match holder between radiants level with canopy 5mm in.when i push the holder above the radiants it pulls the smoke match ,is this ok as its not as the instructions say.

am i correct in thinking that f the working pressure is ok say 20mb but gas rate was down it could as you say be a fire problem .but if working pressure and gas rate is down then its more than likely to be the pipework undersized.

both fires i have had low gas rates on are kinder oasis and kinder kf100 wether this is just a coinsadent

thanks for the advise i used to work for a company doing new builds and maintenance but now working for myself and i am amazed what issues are out there .


thanks ant

using ph matches? try strikes poor fit in the smoke tube but a better/clearer smoke trail less prone to burning regarding pressures agree with reg mans comments

 

[Billy Bob Bob]

using ph matches? try strikes poor fit in the smoke tube but a better/clearer smoke trail less prone to burning regarding pressures agree with reg mans comments

as for kinder just for info most are now flavels both being owned by bfm Europe double posted????? dont know what happened there

 

[buckley plumb]

Hi graham yes using ph matches ,i agree the smoke on them is poor i have to put my glasses on to see the smoke sometimes.

thanks ant