Oftec Questions

[Duker996]

I'm currently swatting up on the oftec regs with a view to doing the ofec training and I've found a couple of things I'm unsure about.

The technical book 2 says "there are varying types of flexible oil pipes available with guarantee periods between 1 and 5 years. Where the flexible oil line is marked with a date stamp, the age of the oil line should be established and if out of the guarantee period, replaced immediately."

So you find an oil line date stamped 14, how do you know if it's good for 1 year or 5? Also the last flexible hose I picked up to replace a leaking one for my father in law was stamped ST6 2/14, was this the production date or the expiry date as it was only a few weeks ago I picked this up?!

And lastly under section 6.11.7 Initial tests it explains using your smoke pump 3 times during one service. Do people actually do this as I was led to believe you use it once just before inserting your FGA?

:dizzy2:

 

[Duker996]

Anybody...........maybe even Malcolm?!

 

[Best]

You will get to know what hoses are for 5 year life and which are just one year.
Most standard braided hoses are only one year life supposedly.
The green or red hoses are long life. Date is normally manufacturing date.
I doubt if you will get much questions on those.
Using the smoke pump is a good idea to prevent sticking an analyser onto a very badly burning boiler where it might damage the analyser.
Using a smoke pump only once is okay if the smoke number is 0, but that may not mean the boiler setting is correct - it could have too high an air setting. You really need to take a few smoke tests while adjusting the air before each test to get the smoke paper to show very slight sooting and then raise air & take another to get 0 number, then add slight more air and the analyser reading should then be close. A modern burner normally has its highest efficiency when smoke number is slightly dirty at say, number 1 or 2, but this is impractical as boiler would soot up easily. Fifteen % CO2 in theory is ultimate efficiency from Kerosine, but not achievable as you can only achieve proper lasting efficiency with 12% or lower, as per what MIs state. That also depends on air temperature and particular boiler/ flue and location. In reality as long as you are sure the burner combustion is on the clean side, you could put the analyser on & adjust the air as needed if boiler gases up to temperature.
You'll be lucky if your oftec exam tells you anything sensible for real world work.

 

[Duker996]

Thanks Best, thats the kind of answer I needed! :wink:

Nice tip on making the boiler soot a little then setting it to the correct setting, not something I'd have thought of! As for braided hoses I would change them yearly then, for the price you might as well!

Lots of what I've been reading lately has said Oftec won't teach you too much, more so just their current regs but not how to work on boilers a such. I guess thats what manufactures courses are for once Oftec is achieved.

 

[Best]

Braided hoses are dodgy & although they can last years, when you, or someone else touches them they can start weeping soon after. So best to replace them.
The Bentone braided hoses seem to last & last strangely.
Be careful of the black "long last" hoses as they can be poor & crack whole thickness of rubber wall.
As to analysers, - you can do the reverse and start with the air high & reduce air slightly while analyser is reading gases until you get proper result. All once boiler has been going long enough for correct flue temperature