worcester junior 28 i greenstar

[desrob]

done a flue gas analyser check on this model,got a reading of 0.0016 ,fan speed ok,heat input ok,i gave heat exchanger a clean,tested again got a reading of 0.0016, i phoned tech department up they said as long as ppm were below 200 ,and this reading shows that they were, they said alls ok ,co/co2 % were all ok aswell.this seems to go against what i was taught or am i missing some thing.

 

[mfgs]

Seems fine to me. Worcester state below 0.0020 and less than 200ppm. I dont really know what you think is wrong?

 

[Blake]

I don't understand, what figures were you expecting?

 

[GQuigley67]

think as long as its below 0.004 it doesnt need to be cleaned/serviced

 

[mfgs]

think as long as its below 0.004 it doesnt need to be cleaned/serviced

Worcester state it must be below 0.0020. CO less than 200ppm. co2 max 9.8 +/- 0.5, min 9.2 +/- 0.5.

 

[GQuigley67]

aw ok I was just going with basic guidelines but obv manufacturer knows best

 

[Billy Bob Bob]

and did you check in service mode? on high and low?

 

[desrob]

yes gas man checks were done in service mode,on previous checks i'm sure it was three 0.eg, 0.0004 ,and i'm sure this is what i was taught, any thing over service required,below 0.0008 acceptable.help!!!!!!!!

 

[GQuigley67]

you can range from 0.0001 to 0.008 before service is required I believe

 

[desrob]

you can range from 0.0001 to 0.008 before service is required I believe

these 0 are confusing me i thought i had it sorted ,then this today(0.0016),can you confirm that indeed is the case,to be honest,i'm ordering an gas analyser testing book .

 

[GQuigley67]

if it was wrong someone on this site would of said so I'm like you not clued up on them just recently done my CPA1 but these guys use them all the time

 

[Gascat]

i was taught always follow manufacturers instructions you cant go wrong.on the greenstar junior 28i you need to measure the fan pressure from the test point if you get a negative reading less than 3.9 mbar then the heat exchanger needs cleaning.the co2 readings are irrelevant in respect to whether or not the heat exchanger needs cleaning. if your co2 readings are wrong you need to reset the gas air ratio .happy heating .

chris

 

[Blake]

See this thread: http://www.ukplumbersforums.co.uk/gas-safety-register-forum/12870-flue-gas-analysis-high.html

 

[aggis]

Normally HE boilers are set up on co2 levels, these boilers have very near perfect [stoichometric] ***bustion, so the co level is very low & co2 levels approx 8.8- 10. These 2 factors give you the ratio. The manufactures that states, less than 0.002 are wanting near perfect combustion.

If you've tested & got 0.0016 ratio, then stripped serviced & got 0.0016 again, all is well, if you retested 3-4 hours later it would have dropped, because there'll be some dust/ contamination drifting around the heat exchanger straight after cleaning.

 

[wnjswozo]

always use mi with fga,.004/.008 are guidence to action levels.
why cant manufacterers put this info on data badge?