Can you return air from a Laudry room using Gas-fired dryers?
Can you return air from a Laudry room using Gas-fired dryers?
(OP)
We have a Commercial laundry room using 5 gas-fired dryers. Can one return air from the space to the AHU? I remember reading a ANSI 4 CFM/1000 btuh of OA rerquirement with sliding scale of OA somewhere here in this forum for recirculating units.
I am still searching for that thread, if anyone can me to it, it will be much appreciated. Understand that this is applicable to a gas-fired RTU, is this 4 CFM/1000 btuh OA applicable for a space gas-fired dryer?
Thank you.
I am still searching for that thread, if anyone can me to it, it will be much appreciated. Understand that this is applicable to a gas-fired RTU, is this 4 CFM/1000 btuh OA applicable for a space gas-fired dryer?
Thank you.





RE: Can you return air from a Laudry room using Gas-fired dryers?
Can anyone pitch in to this post?
Thanks
RE: Can you return air from a Laudry room using Gas-fired dryers?
Usually those dryers, you have all the air they need ducted in the back, sometimes framed in
So you have a furnace or an AHU supplying this space with air, you want to know if you can also condition another part of the building with the same system?
I can't give you any code reference but I would give the laundry its own small system.
Take the "V" out of HVAC and you are left with a HAC(k) job.
RE: Can you return air from a Laudry room using Gas-fired dryers?
Design the Laundry room as a self-contained system. Ideally this room shpuld have one outside wall exposure to make life easy for the dryer vents, and combustion air requirements.
RE: Can you return air from a Laudry room using Gas-fired dryers?
I thought that Spaces with Gas-fired equipment needed POSITIVE pressure to keep the flame alive and insure that flues are not pulled back into the space.
GMcD, would you please elaborate on the need for negative pressure? do you mean neagtive pressure in relation to the adjacent washer room? or to outdoors?
Wouldn't a make-up air hood direcly ducted to the dryers enclosure be enough? and AHU with SA/RA for the adjacent washer room be OK? may be use the RA only for night set back and switch 100% OA when any dryer is enabled, then again, using 100% OA with no RA will contribute to positive pressure.
I take it that you mean that the dryer room should have some sort of direct fired gas-furnace using 100% OA make-up with VFD controlled by dryers step firing AND space pressure sensor.
Dryers are indeed inclosed in as AbbyNormal says. Provided with combustion air per code. However, the enclosure cannot be considered fully tight since it communicates with the Washer room around the dryers framing.
Thank you
RE: Can you return air from a Laudry room using Gas-fired dryers?
I think with correctly sized hoods right behind the dryers then the room would go slightly negative and the majority of the air to dry the clothes would come from the outside.
Perhaps a small simple exhaust fan could maintain a slight negative when the dryers are off, just run the fan steady.
With a small independent system heating the laundry area, R/A slightly lower than supply air, small amount of fresh air in the supply to compensate for the small exhaust fan. Dryers with the hoods hoods take care of themselves.
Dryer is like a small direct fired unit, not like an atmospheric vent that will back draft.
Is this a mountain or a mole hill?
Take the "V" out of HVAC and you are left with a HAC(k) job.
RE: Can you return air from a Laudry room using Gas-fired dryers?
RE: Can you return air from a Laudry room using Gas-fired dryers?