Unit heater venting question

clammy

Looking at replacing 2 renzor unit heater in a warehouse the units that are being replaced are natural draft  and there flue share a common properly sized b vent chimmey which terminates above the roof ,the new unit heaters are equipted with power vents on them my question is can these two power vented applicenes  share a common b vent chimmey or do they need to each be vented seperatly .Usually in most warehouse the unit heater are spread out and each unit has it own b vent chimmey but in this case they are not but are at a 45 degree angle from each other and i really don't want to have any vent issues where one unit is running and another one start but can't make the air proving switch .The other of course issue is the roof is shot and has bubbles the size of sand dunes and i would really not like to have to make another peneration .Thanks for any input peace and good luck clammy

Tim McElwain

It should not

be a problem unless they are connected into a common vent connector which then connects to the common vertical B vent.



If they enter the common vent at different levels it should be okay.



If you have problems try connecting them with a wye fitting instead of a bull head tee..



Obviously I am giving advice here with out seeing what the system looks like.

clammy

thanks timmie

Thanks Timmie i was planning on fabing up a double wye fitting and capping the bottom and have each unit vent tie in on  the horizontal (wye fitting sitting vertical into the bottom of the b vent) thanks again for a little confrimation  peace and good luck clammy

Henry

Reznor

If you are replacing the units with Reznor UDAP power vented models, you CANNOT comon vent. The manufacturer's specific instructions spell out the venting as Cat III, single vent.



You must always check the manufacturer's instructions before deciding on a venting arangement even if it is a cat I appliance.



Henry