CLEAN BURN CB-200-CTB, Руководство оператора, Страница: 42 / 148

Coil Tube Boiler Operator's Manual: Models CB-200-CTB, CB-350-CTB, and CB-500-CTB
4-4
Combustion Air Requirements
The CTB system designer/installer must ensure that there is the proper amount of combustion air in the boiler/
mechanical room.
Refer to Figure 4C.
Combustion Air is the required amount of air that the equipment needs to permit the satisfactory
combustion of oil, the proper venting of combustion gases, and to maintain a safe ambient temperature within the
space at safe limits under normal conditions of use.
NFPA 31 requires the following for combustion air:
Units located in confined spaces (units in a boiler room/mechanical room) must have two (2)
permanent openings, one near the top of the enclosure and one near the bottom of the enclosure
as follows:
1. If all of the air is taken directly from the outside of the building by use of vertical ducts -
each of the two openings must have a total free area of not less than 1 square inch per 4,000
BTU/hr (35 square inches per gallon of oil) of the total appliance(s) input rating (NFPA 31,
Section 5.4.2.2).
2. If all of the air is taken directly from the outside of the building by use of horizontal ducts -
each of the two openings must have a total free area of not less than 1 square inch per 2,000
BTU/hr (70 square inches per gallon of oil) of the total appliance(s) input rating (NFPA 31,
Section 5.4.2.2).
3. If all of the air is taken directly from inside of the building - each of the two openings must have
a total free area of not less than 1 square inch per 1,000 BTU/hr (140 square inches per gallon
of oil) of the total appliances(s) input rating (NFPA 31 Section 5.4.1).