boiler room

Bob Morrison_3

Irene,

Read section 5.3 the National Fuel Gas Code (NFPA 54)for combustion air requirements for gas equipment. Then consult your local code for addtional requirements. In a nutshell, you'll need to determine if the boiler room is a "confined space" and act accordingly. It's somewhat involved, but not difficult.
As an example, in MA., if the boiler room can be directly ducted to the outdoors, then two openings are required, one each at the top and 12" above the floor of the room, each with a square inch of "free area" per 4000 BTUh of total appliance input.

Bob Morrison

Irene_2

boiler room

I finally took a sledge hammer and knocked down the wall to my boiler room. I hauled out two old gross gas boilers for steam systems as well as a 100 gallon dead HWH. Remove every thing that was and wasn't hooked down. Now I am going to put one gas fired boiler for my steam system and one HWH or tankless heater. They will be vented up the chimney flue (newly lined) Now my question is, when I go to put the walls back up, what kind of air source do I need? Do I need to run duct work across the basement to the outside or is the basement air enough? Should I put grates in the boiler room walls to open it up to more basement air? In all the pictures on the wall I haven't noticed many inside boiler rooms so I haven't noticed how they are vented..Yes, I did ask the company that is going to do the install and the two people doing the heat loss gave me two opposite answers, so I thought I would get some input.
Thanks
Irene

tim smith_2

combustion air

Most basements do not have adequate volume per the code to supply combustion air for a boiler. The uniform mechanical code says that you need 50 cubic feet for every 1000 btus, also it space can't be of unusual tightness. So if your basement is 1000 sft with 8 ft ceilings, that will only be sufficient for 160000 btus input. If you run horizontal ducts out to out side you need 1 sq inch per 2000 btus x 2 ducts or 1 sq. inch per 4000 if they are vertical ducts. One duct to be located high on wall of boiler room and 1 with in 12" of floor. This is from memory with out code book in front of me but I'm quite sure. A confirmation with inspector would be good before proceeding.

Unknown

Irene, you need to find

out what code is used in your area. When you find out let me know and I will give you all the particulars you need to determine air for combustion.

The new National Fuel Gas Code 2002 (NFPA 54/ANSI Z223.1) uses a new procedure for air for combustion.

Unknown

The Mass Gas Code

is only up to NFPA 54 (1992), it does not have changes made in 1996 and 2002 for Air for Combustion.