Ceiling vents in mfg homes

[Denray]

Sometimes I see ceiling registers, in manufactured homes, in all the rooms in addition to the floor registers for the furnace. In the hallway there will be some ceiling registers too. Next to one of the hall ones there will be a fan behind a register. They don't come on when the heater is on. What are they for?

[Marc]

HUD-Codes have exhaust fans (usually in the ceiling) in bathrooms and kitchens.

I've no idea why someone would put an exhaust fan in the hallway, HUD-Code or not.

Marc

[mjr6550]

I don't see many manufactured houses and have not seen this. One thought for the registers is jump ducts for return air. As for the fan, no idea.

[Jim Katen]

The only time I see them is as jumpers.

[Greg Booth]

..........in the late 80's and early 90's a number of brands were using small fans as part of an effort at fresh-air introduction. The concept was driven by the formaldehyde off-gassing issues within the industry. I've seen fans located in rooftop vents, similar to bathroom exhausts, that the owner never knew existed 'til they heard funny noises when the fan began to fail/squeak. Not one of the industry's better ideas[:-paperba...........Greg

[Denray]

Thanks Greg,

Googling around it was kind of looking that way. Still no obvious information on it. This mfg hm was an 05 model. I've only seen it one other time.