The Fatal Venting Error in Room 225, This weeks video

RayWohlfarth

This video discusses three cases of sidewall venting done wrong, resulting in four fatalities. Sidewall venting of flue flue gases is a cost effective solution if done right.

https://www.youtube.com/watch?v=80M3vuE4O4o

Steamhead

I'm surprised this doesn't happen more often, based on some things I see in the field……….

RayWohlfarth

@Steamhead I know its kinda crazy what installer do

clammy

Its kinda amazing that this continues to happen . It makes me think who are the idiots who do these types of job without any clear thoughts of the end results just plain stupid or just kids listening to a blind eyed owner or sales guy . i Kinda believe that also that most gas pool heater should not installed within a building unless hard wired in a co monitor which dis engages the power to the unit. The saddest and stupidest is hotels where the pool pump and filters are housed in the same indoor mech room w all the pool chem w usually zero outside combustion air and in a few cases no indoor transfer grills to allow fresh building air into the room . The other note is most pool guys do not service pool heaters ain t there jobs so they usually go un serviced and usually that's part of the issue as the draft collector rots and drops on the heat exchanger and bang you got a issue and it s been a while since servicing a gas pool heater but i would gather two spill switches might help being i don't ever remember seeing them but i'm old and forgetful now .

Thanks Ray

peace and good luck clammy

michaelmiracle

I work in a school in Denver. The hot water boiler for the heating system is side wall vented. Do you see any problem with this setup? It's been this way since the install in 2015. Probably the A/C unit wasn't there at the time. Most likely they will not be run at the same time but I can't guarantee that.

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Zman

I don't believe that type of AC unit is actually pulling air into the space. There are several code violations in that picture. At first glance, the intake for the boiler room is directly below, which is dangerous for folks in the boiler room. You are not allowed to exhaust at that height into the alley. The vent also needs to be protected from vehicular damage. I am sure there are others.

bburd

Codes vary, but I suspect the exhaust vent is too close to operable windows, and it probably should be rotated 90°. It should not significantly affect the air conditioner.

michaelmiracle

I have boiler inspector coming for the annual inspection of the steam boiler ( we have both steam and HW) so I'll ask him what he thinks about it, as far as Denver code.

pedmec

@michaelmiracle That unit is considered power vented which would require you to be 4" above any fresh air intake located within 10'. in mass. that looks like the old combustion air inlet for the boiler room. also 3' from in inside corner to prevent wind eddys

michaelmiracle

I looked up the manual on this boiler. PKMach 750. It's interesting how they show it. I don't have an intake affixed to the boiler, just vented to the boiler room. But here it is;

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