Electrical - Lennox MERIT Series Installation Instructions Manual

Leak Check
After gas piping is completed, carefully check all field-in-
stalled piping connections for gas leaks. Use a commer-
cially available leak detecting solution specifically manu-
factured for leak detection. Never use an open flame to
test for gas leaks.
NOTE - If emergency shutoff is necessary, shut off the
main manual gas valve and disconnect the main power
to the furnace. The installer should properly label these
devices.
CAUTION
Some soaps used for leak detection are corrosive to
certain metals. Carefully rinse piping thoroughly after
eak test has been completed. Do not use matches,
candles, flame or other sources of ignition to check for
gas leaks.
The furnace must be isolated from the gas supply sys-
tem by closing the individual manual shut-off valve during
any gas supply system at pressures greater than or equal
to ½ psig. (3.48 kPa, 14 inches w.c.). This furnace and
its components are designed, manufactured and inde-
pendently certified to comply with all applicable ANSI/CSA
standards. A leak check of the furnace and its components
is not required.
IMPORTANT
When testing pressure of gas lines, gas valve must be
disconnected and isolated. See figure 28. Gas valves
can be damaged if subjected to pressures greater than
1/2 psig (3.48 kPa, 14 inches w.c.).
MANUAL MAIN
SHUT-OFF VALVE
WILL NOT HOLD
NORMAL TEST
PRESSURE
1/8 NPT PLUG
CAP
Figure 28

Electrical

ELECTROSTATIC DISCHARGE (ESD)
Precautions and Procedures
CAUTION
Electrostatic discharge can affect electronic
components. Take precautions to neutralize
electrostatic charge by touching your hand
and tools to metal prior to handling the
control.
ISOLATE
GAS VALVE
FURNACE
Fire Hazard. Use of aluminum wire with this product may
result in a fire, causing property damage, severe injury
or death. Use copper wire only with this product.
Failure to use properly sized wiring and circuit breaker
may result in property damage. Size wiring and circuit
breaker(s) per Product Specifications bulletin (EHB) and
unit rating plate.
The unit is equipped with a field make-up box on the left
hand side of the cabinet. The make-up box may be moved
to the right side of the furnace to facilitate installation. If
the make-up box is moved to the right side, clip the wire
ties that bundle the wires together. The excess wire must
be pulled into the blower compartment. Secure the excess
wire to the existing harness to protect it from damage.
INTERIOR MAKE-UP BOX INSTALLATION
Right Side
BOX
Refer to figure 30 for schematic wiring diagram, field wir-
ing and trouble shooting.
The power supply wiring must meet Class I restrictions.
Protected by either a fuse or circuit breaker, select circuit
protection and wire size according to unit nameplate.
NOTE - Unit nameplate states maximum current draw.
Maximum over-current protection allowed is 15 AMP.
Holes are on both sides of the furnace cabinet to facilitate
wiring.
Install a separate (properly sized) disconnect switch near
the furnace so that power can be turned off for servicing.
Before connecting the thermostat, check to make sure
the wires will be long enough for servicing at a later date.
Make sure that thermostat wire is long enough to facilitate
future removal of blower for service.
Page 23
WARNING
CAUTION
Figure 29