rapid fire unit gas smell

[in-trane-ing]

going to check out a rapid unit tomorrow they say they can smell gas when it comes on.was there 2 weeks ago for the same reason.we adjusted the gas pressure because it only smelled when high fire came on. now im thinking my digital manometer isnt reading the gas pressure correctly or maybe its something else.anyone got any other ideas
thanks

[in-trane-ing]

forgot to mention this is a direct fire unit, cant remember off the top of my head what the differential pressure is. Im sure the problem is with the high fire gas pressure because the gas smell comes for just a few seconds when the high fire comes on has anyone ever had a problem using a digital manometer on these. im going to takemy utube tomorrow to check
thanks

[chilly123]

may i suggest you smoke test the heat exchanger:)

[techhead]

How old is the unit if it's over 3 yrs old you may need to clean the burners.
here's something to check go to high fire and see how much burner lift you
have. might be time to drill the burner.

Hope this helps

[slimwoodie]

may i suggest you smoke test the heat exchanger:)


there isn't any effin' ....Heat Exchanger ....:rolleyes:

go back to the Resi forum ...

[slimwoodie]

How old is the unit if it's over 3 yrs old you may need to clean the burners.
here's something to check go to high fire and see how much burner lift you
have. might be time to drill the burner.

Hope this helps

good post ..:)

[in-trane-ing]

thanks guys,
checked out the unit today. forced high fire, gas pressure screw backed all the way out and carried a 4 foot flame at 5" wc, and tripping high limit. factory pressure rated 9.5, have -2.0" no fire pressure so I need 7.5". Called rapid,they say profile dampers adjusted wrong but magnahelic gauge reads .9,right in the middle of factory rating. going back monday w/ some help. unit is new install. I went to the factory 3 day class but but that is mostly startup procedures not troubleshooting and I dont have much hands on. I have no idea on this. Probably something simple. any ideas
thanks again

[slimwoodie]

gotta go back to design figures ...

airflow

delta p across damper

gas press

temp rise ...

the solution ..

is in them figgers :)

[y7turbo]

there isn't any effin' ....Heat Exchanger ....:rolleyes:

go back to the Resi forum ...


thats was funny

[slimwoodie]

Aaaahh...

you'll fit in here Fine ...:)

[chilly123]

there isn't any effin' ....Heat Exchanger ....:rolleyes:

go back to the Resi forum ...

you and i are talking about two different types of equipment,one of which is produced locally called rapid fire [ a industrial unit] and no i do not belong in the resi forum:mad:

[slimwoodie]

[QUOTE=in-trane-ing;1664727]forgot to mention this is a direct fire unit,[QUOTE]


Chilly 123 ...

whassat ...???

[slimwoodie]

you and i are talking about two different types of equipment,one of which is produced locally called rapid fire [ a industrial unit] and no i do not belong in the resi forum:mad:


C'mon ... Chilly ..

give it back ...

the last Instuctor
had a melt down ...

rise above it ...:)

[slimwoodie]

are you referring to ..Rapid Engineering ..??

they make .. Both ...

get out yer Checkbook

[chilly123]

nope you would know if you if you ever had to work on it. worst thing to ever be inflicted on the industry, by the way no meltdowns here:D

[slimwoodie]

well is it Direct Fired, or not ..??

[keepyoucool2003]

it's posted more than once...

forgot to mention this is a direct fire unit, cant remember off the top of my head what the differential pressure is. Im sure the problem is with the high fire gas pressure because the gas smell comes for just a few seconds when the high fire comes on has anyone ever had a problem using a digital manometer on these. im going to takemy utube tomorrow to check
thanks

[Aircooled81]

what did the gas smell end-up coming from?
Did you solve the mystery.
I had a gas pack boggle minds for days, only smelled gas when it ran in heat, ended up being loose unions after the gas valve before it hit the main burners. The gas came out of the cabinet, and was sucked into the outside air/econo dampers.

[in-trane-ing]

turns out the low fire gas pressure wasnt high enough. When I looked in the little window on the door it looked like the flame was all the way across, but when I finally opened the door to look at it I could see the last set of burners werent lighting therefore dumping raw gas into the space. Feel kinda stupid about that. Seems like there should be some type of flame sensor at the end of the burner also but there isnt
Thanks guys

[bobby m]

Also check the gas manifold tee's for any unplugged 1/8'' holes,i once was getting a gas smell complaint and it turned out they used tees in the manifold that had holes in then for pressure taps (they werent tapped or plugged)can't remember for sureif it was a rapid unit.