INSTALLATION AND OPERATION INSTRUCTIONS
3-4
TANKLESS WATER HEATER 199
INSTALLATION AND OPERATION INSTRUCTIONS
3-4
TANKLESS WATER HEATER 199
3.4 FUEL CONVERSION
T
he unit is factory fire-tested to operate
with natural gas as shown on the rating
plate. Firing a unit with a fuel other than what is listed on the rating plate is
prohibited unless the following conversion procedure is completed by a qualified
technician.
Fuel conversion requires hardware adjustments (orifice replacement) as well as
measurement and possible tuning of the low fire mixture. Detailed instructions
including parts and labeling are found in Fuel Conversion kits.
Refer to Table 10
for the correct kit number.
NATURAL GAS
PROPANE
CO
2
VALUE (%) AT HIGH FIRE WITH THE FRONT COVER OPEN¹
Max. CO
2
value
10.3%
11.0%
Min. CO
2
value
8.7%
9.8%
CO LIMIT (PPM) AT HIGH FIRE WITH THE FRONT COVER OPEN²
Max. CO limit
< 150ppm
<250ppm
CO
2
VALUE (%) AT LOW FIRE WITH THE FRONT COVER OPEN
Max. CO
2
value
= value at High
= value at High – 0.3%
Min. CO
2
value
8.7%
9.5%
Table 11: Acceptable High and Low Fire Combustion Values
¹ High Fire CO2 is set by the orifice installed and is not field adjustable.
² If the CO reading exceeds the limit in this table, the unit must be shut down until the
cause of excessive CO readings is corrected.
The following procedure must be carried out by a qualified technician.
1.
Ensure that the gas supply is turned off at the manual gas valve.
2.
Disconnect the electrical power.
3.
Disconnect the nut at the gas valve outlet (top of the gas valve) and remove
the orifice and O-ring.
4.
Insert the correct orifice into the O-ring, and re-install into the nut at the gas
valve outlet (top of the gas valve) and then tighten the nut.
5.
Restore the gas supply by opening the manual gas valve.
6.
Test for leaks by using an approved leak detection solution on all joints.
7.
Carefully follow the
“Prior to Start-Up” – Section 3.2 and “Commissioning” –
Section 3.3 procedures on the preceeding page 3-2.
DANGER
Operating any unit using
a fuel other than the fuel
listed on its rating plate is
prohibited. If the information
in this section related to
conversion to alternative
fuels is not followed exactly,
a dangerous situation can
result, leading to fire or
explosion, which may cause
property damage, personal
injury, or loss of life.
Figure 33: Orifice and O-ring
PROPANE ORIFICE CHART
MODEL
ORIFICE
SIZE
199,000 Btu/hr
199,000 Btu/hr
535
NATURAL GAS ORIFICE
CHART
MODEL
ORIFICE
SIZE
199,000 Btu/hr
199,000 Btu/hr
660
WARNING
Ensure the part kit and
orifice are correct for the
appliance model and fuel type
prior to performing the fuel
conversion.