Service Manual

49
LED LED Status Indication Possible Causes Corrective Action(s)
Off • Normal condition • None • None
• Control power up
• Learn button depressed
Rapid Flashing • Normal network traffic • Contr ol is “talking” on
network as expected
• None
• Data 1 and data 2 wires reversed
at furnace, thermostat or
communicating compatible
outdoor AC/HP
• Check communications
wiring (data 1/ data 2
wires).
• Short between data 1 and
data 2 wires.
• Check wire connections at
terminal block
• Short between data 1 or
data 2 wires and R
(24VAC) or C (24VAC
common).
• Check data 1/ data 2
voltages.
Green
Receive
LED
2 Flashes • Out-of-box reset • None
On Solid • Data 1/ Data 2 miss-wire
Red
Communications
LED
Operational Checks
BURNER FLAME
The burner flames should be inspected with the burner com-
partment door installed. Flames should be stable, quiet, soft,
and blue (dust may cause orange tips but they must not be
yellow). Flames should extend directly outward from the burn-
ers without curling, floating, or lifting off. Flames must not
impinge on the sides of the heat exchanger firing tubes.
Check the
Burner Flames for:
1. Stable, soft and blue.
2. Not curling, floating
or lifting off.
Burner Flame
Combustion Quality
Combustion quality can be affected by several factors. Major
factors are venting and draining.
Venting
The venting system should be planned and installed with
the following in mind;
• Should not be longer than necessary
• Use 45°elbows rather than 90° elbows when possible
• Must not sag or otherwise trap condensate
• Use longest radius fittings possible
• If using 3" venting, make the transition from 2" to 3"
as close as practically possible
• Make sure there is no flue gas recirculation into the
combustion air pipe
Condensate Drainage
Furnace combustion can be affected if a furnace is holding
condensate. Check for proper connections of drain hoses,
make sure furnace condensate trap is clean. Make sure
furnace is not improperly sloped. Make sure air condition-
ing coil drain is not interfering with furnace drain.
Other Causes
1. Manifold Gas Pressure must be set for the gas being
used, Natural or L.P., high and low firing rates. If con-
verted to L.P. gas, check size of all orifices
2. Remove Draft Inducer, Check the integrity of the gas-
ket between the inducer and the collector box cover,
any air leak here will have a negative effect on combus-
tion. Check the orifice hole in the collector box, it must
be free of burrs on both sides
3. Make sure burners are clean, not out of position and
line up correctly with exchanger tubes, including the heat
exchanger orifice plate between the burners and the heat
exchanger tubes, make sure it is not loose, missing a
screw or hanging down between the burners and heat
exchangers causing flame impingement.
4. Make sure the field installed gas line is not binding and
causing distortion of burner assembly
OPERATIONAL CHECKS