GB-20
Large Orifice
Extended Coverage Light Hazard
Recessed Pendent and Pendent
Glass Bulb Automatic Sprinkler
Product
Description
Technical
Data
For specific listing requirements, see the appropriate
information contained in this brochure.
The Central Model GB-20 Large
Orifice Recessed Pendent and
Pendent Automatic Sprinkler is a low
cost, aesthetically pleasing unit,
specifically designed for Extended
Coverage/Light Hazard applications
per NFPA 13.
The Model GB-20 Sprinkler incor-
porates a specially designed deflector
that provides a much greater area of
coverage than most commercial
sprinklers. A 2-piece recessed
escutcheon assembly that provides
for
3
⁄
8
"
(9.5mm)
of field adjustment is
available.
The Model GB-20 has a nominal K
factor of 7.8
(112.5 Metric)
, a maximum
temperature rating of 200
°
F/93
°
C,
and a maximum working pressure of
175 psi
(12.1 bar)
.
The Model GB-20 is available in
three standard finishes, brass,
chrome plated and white painted. Its
mating escutcheon plate is available
in three standard finishes, brass
plated, chrome plated and white
painted with additional special
painted finishes available.
Operation: The glass bulb capsule
operating mechanism contains a
heat-sensitive liquid that expands
upon application of heat. At the rated
temperature, the frangible capsule
ruptures, thereby releasing the orifice
seal. The sprinkler then discharges
water in a pre-designed spray pattern
to control or extinguish the fire.
Model: GB-20
Style:
Recessed Pendent and
Pendent
Escutcheon:
Model ELO Recessed
(2-piece)
Note: Only the Model ELO “Recessed”
(2-piece) Escutcheon may be used.
Substitution of other “recessed”
escutcheons may impair the operating
sensitivity and distribution pattern.
Wrench: Combination Wrench or
GB-20 Wrench
Orifice Size:
17
⁄
32
"
(13.5 mm)
K-Factor: 7.8
(112.5 metric)
Nominal
Thread Size:
3
⁄
4
"
(20 mm)
N.P.T.
Temperature Rating: 155
°
F/68
°
C
175
°
F/79
°
C
200
°
F/93
°
C
Approvals: U.L., U.L.C.,
M.E.A. 312-92-E
Maximum Working Pressure:
175 psi
(12.1 bar)
Factory Hydro Test: 100% at
500 psi
(34.5 bar)
Standard Finishes:
Sprinkler: brass, chrome plated
Corrosion-Resistant Coatings:
white, black, off-white
Escutcheon: brass plated, chrome
plated, white painted
Length:
2
1
⁄
16
"
(52.4 mm)
Width:
1
11
⁄
16
"
(42.9 mm)
Diameter
Weight:
3.2 oz.
(90.7 grams)
Patent: Pending
Manufactured by: Central Sprinkler Company
451 North Cannon Avenue, Lansdale, Pennsylvania 19446
Extended
Coverage
Light
Hazard
Recessed
Pendent and
Pendent
Sprinkler
No. 2-9.0
GB-20
2-98
OBSOLETE
