Installation Guide

WHL-648 Rev. 000 Rel. 002 Date 1.3.18
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C. Additional Precaution for Excess Flow Valve (EFV)
If an excess ow valve (EFV) is in the gas line, check the manufacturer’s
minimum and maximum ow capacity ratings. An improperly sized
EFV will not allow for a full ow of gas to the appliance and will cause
the appliance to malfunction. See Figure 38.
Figure 38 - Excess Flow Valve (EFV)
D. Checking Gas Pressure at the Appliance for Proper
Operation
NOTE: Refer Figure 39 when checking gas pressure. Loosen the bolts
before checking the gas inlet pressure.
1. The appliance and its individual shuto valve must be disconnected
from the gas supply piping system during any pressure testing of
the system at test pressures greater than ½ psi (3.5 kPa).
2. The appliance must be isolated from the gas supply piping system
by closing its individual manual shuto valve during any pressure
testing of the gas supply piping system at test pressures equal to or
less than ½ psi (3.5 kPa).
The minimum and maximum inlet gas line pressures must meet the
requirements shown in Table 25.
Natural or LP Gas
Minimum Pressure 3.5” WC
Maximum Pressure 14”WC
Table 24 - Gas Pressure Requirements
Do not re (operate) the appliance until all connections have been
completed and the heat exchanger is lled with water. Doing so
will damage the appliance and void the warranty.
Figure 39 - Gas Valve Detail
E. Setting and Verifying the Combustion Setting
1. After the appliance has red, ip DIP switch seven (7) to the ON
position (low re). Proceed to check appliance combustion values.
NOTE: Use a calibrated combustion analyzer to ensure CO and CO2
values are within the range shown in Table 26.
It is required to use a calibrated combustion analyzer to verify nal
adjustment according to the combustion chart (Table 26). Failure to
do so could result in serious personal injury or death.
If the readings obtained are lower or higher than the combustion
readings in Table 26, use a 4mm Allen key to adjust the oset screw
in a clockwise (positive) or counterclockwise (negative) direction
(approximately 1/4 turn). See Figure 39. Check your combustion values.
Repeat this procedure until the values obtained on the calibrated
combustion analyzer agree with those stated in Table 26.
NOTE: If the appliance makes a whistling sound (harmonics) at
low re, adjust the oset screw in a clockwise (positive) direction
(approximately 1/8 turn). Check your combustion values and ensure
they agree with those stated in Table 26 before proceeding.
2. When low re settings have been obtained, ip DIP switch seven (7)
to its original (OFF) position. This will return the appliance to normal
operation.
3. Flip DIP switch six (6) to ON (high re). Again check combustion
readings with a calibrated combustion analyzer.
NOTE: DO NOT adjust the gas valve oset screw at high re. The oset
screw is only used to adjust combustion values at low re.
4. When complete, ip DIP switch six (6) to its original (OFF) position.
This will return the appliance to normal operation.
5. Allow appliance to operate normally. Ensure it is operating properly.
6. Use a Phillips Head screwdriver to reinstall the appliance cover.
It is very important that the combustion system be set within the
recommended CO measurements listed in Table 26. Visually looking
at the burner does not determine combustion quality. Failure to
measure combustion with a calibrated combustion analyzer and
set the throttle within the recommended CO measurements could
result in property damage, severe personal injury, or death.
Natural Gas LP Gas
Fan Speed Low High Low High
CO PPM <175 <175
CO2 (%) 8 - 9 1/2 8 1/2 - 10 9 - 10 1/2 9 1/2 - 11
Table 25 - Combustion Settings