Gas-Fired Products PTS Series 100 - Manual (Page 37)

Form #43343530
–36– JJuly 08
MULTIPLE HEATER VENTING (CONNECTIONS INTO A COMMON VENT OR MANIFOLD)
Requirements for venting of multiple heaters are the same as described for SINGLE HEATER VENTING except as
follows:
1. The common vent size and total vent height is normally determined by the number of heaters per common
vent, length of horizontal connector runs, and connector rise. Connector lengths should be as short as
possible and have a minimum 1/2 inch per 20 foot fall. Without regard to connector rise and total vent
height due to many possible venting configurations, the following should be observed:
a. Common vent pipe & vent connector diameter should be no less than that shown in the following Vent
Sizing Table.
b. The connector length should be no more than 75% of the vertical portion of vent above the connector.
c. Where possible, use a Y-connector to the common vent.
2. Material for connectors should be constructed of galvanized sheet metal or other approved noncombustible
corrosion resistant material as allowed by state or local codes. All common vent pipe should be double wall,
Type B vent.
3. Avoid unnecessary bends. Limit to two (2) 90º elbows.
4. The entire length of vent connector shall be readily accessible for inspection, cleaning and replacement.
5. Groups of heaters with a common vent must be controlled by a common thermostat.
Multiple Heater Vertical venting arrangement.
Total
Vent
Height
Vent Cap (Leslie
VersaCap Type B)
Flashing
2” (5cm)
Clearance
Thimble
Seal Joint
and Annular
Space
10 ft (305cm)
or less
2 ft (77cm)
minimum
2 ft (77cm) minimum
(when no wall or
parapet exists)
4” Diameter
single wall Vent
W
all or
Parapet
See multiple
vent size table
for diameter
Flue Collar
adaptor
Connections to the common vent
must be arranged to avoid direct
opposition of exhaust products.
Plan View
Flue Adapter
Collar
#10 Self-Drill
Screws
(typical)
4” Vent Pipe
(horizontal position)
Vent Cap
(Breidert or
equivalent Type L)
2” (5cm)
Clearance
Thimble
1/2” (12mm) fall per 20 ft
(6m) toward vent terminal
6” (15cm)
minimum