Boiler Room Design; Boiler Room Air Supply Requirements - Slant/Fin CARAVAN GGT-600E Application Manual

BOILER ROOM DESIGN

Caravan modular boiler systems allow better utilization of floor
space and permit future expansion with minimum cost. Caravan
modules are hand truckable, fit through doorways and often may
be installed around an existing inoperative boiler. They can be
grouped in heating module batteries of single, multiple or angular
rows. Gas-fired boiler systems consisting of 11 or more modules
should be piped in parallel in two or more batteries. Illustrated on
the following page are typical boiler room layouts and dimensional
data on the size requirements of gas-fired hot water boilers.
Figure 7: Correct location of combustion-air supply ducts
BOILER ROOM AIR SUPPLY
To ensure safe, efficient operation, the modular boiler system must
be supplied with sufficient air to support complete combustion,
replacing air entering draft dampers or draft hoods and ventilating
the boiler room or areas.
For additional information, not listed below, see ANSI,Z223.1,
section 5.3.3.
INSTALLATION IN ENCLOSED BOILER ROOM REQUIRES
TWO UNOBSTRUCTED OPENINGS FOR PASSAGE OF
AIR INTO THE BOILER ROOM:
1. Air drawn horizontally from outdoors DIRECTLY
through an outside wall; one louvered opening near
the floor (below burner air inlet) and one louvered
opening near the ceiling (above the highest draft
regulator), each opening with a minimum FREE air
passage area of 1 square inch per 4000 BTUH of total
system input.
2. Air drawn horizontally through HORIZONTAL DUCTS;
one opening near the floor (below burner inlet) and one
opening near the ceiling (above the highest draft
regulator), each opening with a minimum FREE air
passage area of 1 square inch per 2000 BTUH of total
system input.
3. Air drawn VERTICALLY from outdoors; one opening
at the floor and one opening at the ceiling, each opening
with a minimum FREE air passage area of
1 square inch per 4000 BTUH of total system input.
4. Air drawn from inside the building; one opening near
the floor (below burner inlet) and one opening near the
ceiling (above the highest draft regulator), each opening
with a minimum FREE air passage area of
1 square inch per 1000 BTUH of total system input.
IF BOILERS ARE INSTALLED ADJACENT TO OTHER FUEL
BURNING EQUIPMENT, THE AREA OF FREE OPENINGS
MUST BE APPROPRIATELY INCREASED TO ACCOMMODATE
THE ADDITIONAL LOAD.
UNLESS PROPERLY CONTROLLED, AVOID THE USE OF
FORCED VENTILATION, SINCE IT CAN CREATE AN
UNDESIRABLE PRESSURE DIFFERENTIAL BETWEEN
BOILER ROOM AND AIR SOURCE.
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