The Reliable Automatic Sprinkler Co., Inc.,
103 Fairview Park Drive, Elmsford, New York 10523
Model DH56
Model DH56 Recessed
Model DH56 Concealed
Quick Response,
Extended Coverage Sprinkler
Bulle
tin 015 December 2021
Bulletin 015 December 2021
For coverages up to 28 feet wide and 10
feet long
(1)
. 250 psi (17,2 bar) rated.
Features:
1. Coverage for long and narrow spaces such as hall-
ways, corridors, decks and rooms up to 28 feet
wide and 10 feet long.
(1)
2. Deflector to ceiling dimensions are:
4” (102mm) min. to 12” (305mm) max.
3. Minimum spacing between sprinklers 14 feet
(4.3m).
4. Polyester Coated or Electroless Nickel PTFE Plat-
ed Corrosion Resistant Sprinklers
*Concealed Sprinkler is not corrosion resistant
5. UL Listed for extended coverage, light hazard ap-
plications.
6. 5.6 K Factor.
7. Sprinkler is approved for 250 psi (17,2 bar) appli-
cations.
8. Quick response performance.
9. ½” (13mm) adjustment of escutcheon and cover.
10. Concealed cover plate can prevent the sprinkler
from being used for unintended purposes. No ex-
posed thermal element with the concealed ver-
sion.
11. Push-on/thread-off sturdy convenient escutcheon
for recessed and cover for concealed.
12. Factory assembled sprinkler & cup, shipped com-
plete with protective cap for concealed and FP re-
cessed versions.
13. Sprinkler & cup assembly and escutcheon or cov-
er are separately packaged.
14.
Available in a variety of plated and painted finishes.
(1)
See Figure 4.
Approval Organizations
1. Listed by Underwriters Laboratories Inc. and
UL certified for Canada (cULus)
2. NYC MEA 258-93-E
Patents
US Patent No. 7,841,418
Other Patents Pending
DH56 FP Recessed
DH56
DH56 F2 Recessed
Products Description
The Model DH56 family of sprinklers are quick response
extended coverage sidewall sprinklers for use in light hazard
applications. The Model DH56 with SWC cover plate is a
concealed sprinkler that uses Reliable’s push on/thread off
sidewall cover. This sprinkler has the cup factory mounted
and is shipped with a protective cap that protects the 3mm
frangible glass bulb during shipping and post installation fin
-
ishing operations. The DH56 can be combined in the field
with the FP or F2 Escutcheon to make a recessed sprinkler.
The SWC cover plate, FP and F2 recessed escutcheons
have ½” adjustment. The SWC cover plate is attached with
135-degree solder. In the event of a fire the rising ambient
temperature melts the solder and the cover plate is ejected
away by springs exposing the 3mm frangible glass bulb. The
use of a 3mm bulb allows quick response which enables the
sprinkler to apply water to a fire sooner than standard re
-
sponse sprinklers of the same temperature rating.
Application
The Model DH56 is a horizontal sidewall sprinkler intended for
installation in light hazard occupancies in accordance with NFPA
13. These sprinklers are designed to provide fire protection in
long and narrow spaces such as hallways, corridors, decks and
rooms up to 28 feet (8,5m) wide and 10 feet (3m) long. They are
rated for 250 psi (17,2 bar) and can be mounted between 4 and
12 inches (102 and 305mm) down from the ceiling.
DH56 Concealed
with SWC coverplate
