Use and Care Manual

LP-436 Rev. 5.2.18
14
High altitude orices MUST BE installed for water heaters operating
above 7,500 feet. Failure to follow this instruction can result in
property damage, personal injury, or death.
A water heater cannot be used only for space heating applications.
When using a water heater for combination space and potable
water heating, the instructions provided in this manual and the air-
handling unit must be respected, with particular attention paid to
the following:
• All piping and components that are used in the system must
be of a nonferrous type suitable for potable water. This also
applies to any sealant used.
• The water heater must not be connected to any system that
has been previously used for non-potable water heating. This
includes piping because existing piping may have been treated
with chemicals for cleaning or sealing the system in the past.
• If this water heater is to be used for space heating, make sure
all safety codes are respected. Pay special attention to safety
valve pressure and expansion tanks.
• Do not use toxic chemicals to clean the potable water heating
system.
• Where water temperature in excess of 140
o
F (60
o
C) is required
for a space heating application, a mixing valve must be
installed in the potable side of the system. This will temper the
water and reduce the risk of scalding.
• If the incoming water line to the heater is equipped with a check
valve, water meter, or pressure-reducing valve, an expansion
tank must be installed in the system. This will prevent weeping
from the water heater relief valve and premature failure of the
heater due to expansion of water during the heating cycle.
• Before acquisition of a water heater for space heating, it is
necessary to have the area of intended use sized by a qualied
technician. This will ensure that an adequate water heating
capacity will be available for both heating and potable water
supply, and that the application will meet all local codes and
public utility requirements.
NOTE: It is good practice to oversize the water heater to ensure that all
of the potential hot water requirements are available.
The water heater and its gas connection must be leak tested before
placing the appliance into operation. To leak test the system:
1. Turn on the manual gas shut-o valve near the water heater.
2. Use a soapy water solution to test all connections and ttings
for leaks. Bubbles indicate a gas leak.
3. Correct all leaks.
Make sure that the inlet pressure to the water heater does not exceed
14 inches of water column (3.5 kPa) for natural gases.
Pressures in excess of ½ pound per square inch (3.5 kPa) can damage
the main gas valve, resulting in a re or explosion from leaking gas. For
purposes of adjustment, the minimum inlet pressure is indicated on
the water heater rating plate.
If any pressure testing of the gas line is undertaken at test pressures in
excess of ½ psig (3.5 kPa), the water heater and its gas supply manual
shut-o valve must be disconnected from the gas supply piping
system, and the end of the pipe sealed with a female cap. If the testing
is to be undertaken at a test pressure less than ½ psig (3.5 kPa), the gas
supply manual shut-o valve must be closed.
NOTE: The input rating of the appliance is based on installation and
operation at sea level up to elevations of 2,000 ft. Low NOx models are
certied to operate to 2,000 ft in altitude without adjustment.
G. Combination Space Heating and Potable Water Heating
Figure 14 - Water Heater and Air Handler
H. Wiring
This water heater uses an external electrical source for power. It
must be electrically grounded in accordance with all local codes,
or, in the absence of local codes, the latest edition of the National
Electrical Code, ANSI/NFPA 70 in the United States, or CAN/CSA
C22.1, Canadian Electrical Code, in Canada. Failure to properly
ground the water heater can result in property damage, personal
injury, or death.
Before lighting your water heater, check that all of the wires have
been installed correctly. See Figure 16. Inspect local wiring for defects
before installing this product. Verify that all wiring connections
are properly secured. If wiring on the product appears “loose” or
damaged when received, immediately call customer service. If
instructed to replace any of the original wiring, use only 18 AWG
type or greater wire approved for 221
o
F (105
o
C).
If you are installing a side wall power vent kit, use the following
instructions to connect the power venter to the water heater. See
Figures 15 and 16.
1. In the electrical box of the water heater, remove the jumper
between positions 3 and 4 on the terminal block.
2. Install the wires from the power venter control board to the
positions on the terminal block in the electrical box of the
water heater.
If the power venter has been bought through a wholesaler, some
settings need to be changed on the control board before putting
the water heater into operation. The voltage needs to be set at 24
Volts. This can be done by moving the red voltage jumper on the 24V
prongs. For detailed instructions on how to adjust the power vent
settings, consult the Owner’s Manual that comes with the Tjernlund
Power Venter.
If the power venter has been bought directly from the manufacturer,
the settings have been factory adjusted to match the specications
of the water heater. A label will be axed on the box stating that it
was factory adjusted to commercial gas water heater specications.