Raypak Raytherm Finned Water-Tube Water Heaters - Manual (Page 2)

Project Name / Date Division 23 52 33.13 - 2
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 82
percent at full fire.
3. The water heater(s) shall be ASME inspected and HLW-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 70 lbs. /square foot or less.
B. Heat Exchanger
1. The heat exchanger shall be of a single-bank, horizontal-grid design with integral copper fin
tubes, each end of which is rolled into an ASME boiler-quality steel tube 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.
5. The heat exchanger shall incorporate “V” baffles, between the tubes, to ensure complete
contact of the external tube surfaces with the products of combustion.
6. The water heater(s) shall be capable of operating at inlet water temperatures as low as 105°F
without condensation.
7. 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 stainless steel alloy burners shall be of the raised port design with primary fixed air ports,
capable of quiet extinction without flashback at the orifice at firing rates between 20% and
100%, and mounted in a slide out burner drawer for ease of inspection.
D. Pilot Control System
1. The water heater(s) shall be equipped with a 100 percent safety shutdown system. The
standard pilot ignition shall be:
a. Models 133-1826 - An electronic intermittent ignition system with electronic flame
supervision having a nominal 0.8 second flame response time.
b. Models 2100-4001 - An electronic ignition system with electronic flame supervision having
a nominal 0.8 second flame response time, requiring a manual reset on flame failure.
2. The ignition shall be Spark Ignition type with full flame rectification to ensure consistent
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 two LEDs that indicate flame presence and/or system
status.
E. Gas Train
1. The water heater(s) shall have dual gas valve seats per ANSI Z21.10.3/CSA 4.3.
2. 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
2. The water heater(s) shall be equipped with an energy-saving pump control relay
(Economaster II), mounted and wired, which automatically shuts off the water heater pump at
a set period after water heater shut-down (adjustable from three to ten minutes) to avoid
standby losses associated with constant pump operation.
G. Firing Mode