Ducting Systems and Air Ventilation - Air Combustion Venting in Confined Space

My heating boiler (112,500btu), hot water boiler (40,000btu) and dryer (22,000btu) are all located in my 26x24x7.5 basement which makes it a confined space and needs addtional air. Instead of venting to the outside, I would like to vent to adjoining spaces inside. My only two adjoining spaces are the garage and the upstairs into the living area. So I have two part questions:

1. Can I put the two grilles (low and high) on the door or wall seperating the garage and basement or should the garage be completely sealed from the basement?

2. Can I put two grilles (low and high) on the door upstairs seperating the basement and living area? Since the door is on the next level up from the appliances, will the two grilles still be necessary or will one big grille do it? Are there any downfalls to having grilles on this door?

Thanks for any help and responses.

You will need to refer back to the install guides on these appliances. With that kind of load I think you will have to bring in outside air.

Outdoor Air Inlets
􀂉 Inlets are screened.
􀂉 Inlets located so as not to draw air from any of the following locations:
a) Within 10’ of an appliance vent outlet, unless such vent outlet is 3’ above the outdoor air inlet.
b) Where it will pick up objectionable odors, fumes or flammable vapors.
c) A hazardous or unsanitary location.
d) A room or space having any fuel burning appliances therein.
e) Within 10’ of a vent opening for a plumbing drainage system unless the vent opening is at least 3’
above the air inlet.
f) Attic, crawl spaces or garages. That from this: http://www.mybuildingpermit.com/Inspection%20Checklists/03IRCMBPMechanical%20rough%20in%20checklist.pdf

Your County's Building Department should have one similar, or give them a call as each one could be different.
Be safe, G