Project Name / Date
Division 23 52 33.13 - 3
1. The water heater(s) shall be equipped to (a), (b), or (c):
a. Provide full modulation of gas input to any load condition as low as 20% of the full rating of
the water heater (5:1 ratio) without flashback, burning at orifices or improper combustion.
b. Provide staged control of the gas input to the water heater.
c. Provide on/off control of the gas input to the water heater.
H. Water Heater Diagnostics
1. Provide ignition module indicating the following heartbeats (flashes) by LED signal:
“M” Ignition Model (Continuous Retry)
a. 2 flashes per second (“heartbeat”) – Normal operation
b. 2 flashes – Five-minute retry delay
c. 3 flashes – Recycle; flame failed during run
d. 4 flashes – Flame sensed out of sequence
e. 7 flashes – Flame sense leakage to ground
f. 8 flashes – Low 24VAC (secondary voltage)
g. 6+2 flashes – Five-minute retry delay (on every third retry on the same “Call For Heat”
h. 6+3 flashes – On every sixth flame failure during run on the same “Call For Heat”
i. 6+4 flashes – Flame sensed out of sequence for more than 10 seconds
j. ON steady – Soft lockout due to error detected during self-check sequences
“H” Ignition Model (Lockout)
k. 2 flashes per second (“heartbeat”) – Normal operation
l. 2 flashes – Five-minute retry delay
m. 3 flashes – Recycle; flame failed during run
n. 4 flashes – Flame sensed out of sequence
o. 7 flashes – Flame sense leakage to ground
p. 8 flashes – Low 24VAC (secondary voltage)
q. 6+2 flashes – Failed trial for ignition resulting in lockout
r. 6+3 flashes – More than five flame failures during run on the same “Call For Heat” resulting
in lockout
s. 6+4 flashes – Flame sensed out of sequence for more than 10 seconds
t. ON steady – Soft lockout due to error detected during self check sequences
I.
Combustion Chamber: The high-temperature, multi-piece, interlocking castable combustion
chamber liner shall reduce standby radiation losses, reducing jacket losses and increasing unit
efficiency.
J. Venting
1. When routed vertically, the water heater’s flue material and size shall be in accordance with
the National Fuel Gas Code, ANSI Z223.1/NFPA54 latest edition (Category I).
K. Cabinet
1. The corrosion-resistant galvanized steel jackets shall be finished with a baked-on epoxy
powder coat which is suitable for outdoor installation, applied prior to assembly for complete
coverage, and shall incorporate louvers in the outer panels to divert air past heated surfaces.
2. The water heater(s), if located on a combustible floor, shall require an optional separate
combustible floor base.
L. Operating Controls
1. The water heater(s) shall feature an optional temperature controller.
Specifier Note: The remaining items in this section are options. Delete those that are not being
specified.
IMPORTANT:
The Cold Water Start and Cold Water Run Systems cannot be
used on the same water heater.
M. Water Heater Pump - Refer to Equipment Schedule
N. Cold Water Start System
1. The water heater(s) shall be configured with a cold water start automatic proportional bypass
system that ensures the water heater will experience inlet temperatures in excess of 105ºF
within 7 minutes to avoid damaging condensation. The unit will automatically shut down if the
