Raypak 989B 用户手册
Project Name / Date
Division 23 52 33.13 - 2
2.2 WATER
HEATERS
A. General
1. The water heater(s) shall be fired with gas at a rated input of
BTU/hr.
2. The water heater(s) shall be CSA tested and certified with a minimum thermal efficiency of 85
percent at full fire.
3. The water heater(s) shall be ASME inspected and stamped and National Board registered for
160 PSIG working pressure, complete with a Manufacturer's Data Report.
4. The water heater(s) shall have a floor loading of 65 lbs. /square foot or less.
B. Heat
Exchanger
1. The heat exchanger shall be of a single-bank, horizontal-grid design with twelve integral
copper fin tubes, each end of which is rolled into an ASME water heater quality steel tube
sheet.
sheet.
2. The heat exchanger shall be sealed to 160 PSIG rated bronze headers with silicone "O" rings,
having a temperature rating over 500°F.
3. The low water volume heat exchanger shall be explosion-proof on the water side and shall
carry a twenty-year warranty against thermal shock.
4. The headers shall be secured to the tube sheet by stud bolts with flange nuts to permit
inspection and maintenance without removal of external piping connections. The heat
exchanger shall incorporate "V” baffles between the tubes to ensure complete contact of the
external tube surfaces with the products of combustion.
exchanger shall incorporate "V” baffles between the tubes to ensure complete contact of the
external tube surfaces with the products of combustion.
5. The water heater(s) shall be capable of operating at inlet water temperatures as low as 105°F
without condensation.
6. The water heater(s) shall be designed to accommodate field changes of either left or right
hand plumbing and electrical while leaving the tube bundle in place.
C. Burners
1. The tubular burners shall have multiport radial gas orifices, punched ports and slots, be
capable of quiet ignition and extinction without flashback at the orifice, and be manufactured
from corrosion-resistant, titanium-stabilized stainless steel with low expansion coefficient.
from corrosion-resistant, titanium-stabilized stainless steel with low expansion coefficient.
2. The burners will be supplied with a fan-assisted, clean burning, and highly efficient fuel-air
mixture.
D. Pilot
Control
System
1. The water heater(s) shall be equipped with a 100 percent safety shutdown system.
2. The ignition shall be Hot Surface Ignition type with full flame rectification by remote sensing
2. The ignition shall be Hot Surface Ignition type with full flame rectification by remote sensing
separate from the ignition source, with a three-try-for-ignition sequence, to ensure consistent
operation.
operation.
3. The igniter will be located away from the water inlet to protect the device from condensation
during startup.
4. The ignition control module shall include an LED that indicates six (6) individual diagnostic
flash codes.
5. Two external viewing ports shall be provided, permitting visual observation of burner
operation.
E. Gas
Train
1. The water heater(s) shall have a firing/leak test valve and pressure test valve as required by
CSD-1.
2. The water heater(s) shall have dual-seated main gas valve(s).
3. Gas control trains shall have a redundant safety shut-off feature, main gas regulator, shut-off
3. Gas control trains shall have a redundant safety shut-off feature, main gas regulator, shut-off
cock and plugged pressure tapping to meet the requirements of ANSI Z21.10.3/CSA 4.3.
F. Water Heater Control
1. The following safety controls shall be provided:
a. High limit control
b. Flow switch, mounted and wired
c. ____PSIG ASME pressure relief valve, piped by the installer to an approved drain
d. Temperature and pressure gauge
b. Flow switch, mounted and wired
c. ____PSIG ASME pressure relief valve, piped by the installer to an approved drain
d. Temperature and pressure gauge