Service manual

SERVICING
49
If switch reads as noted proceed to Step 3, otherwise re-
place control.
3. Remove the pressure control hose from the control and
interconnect with an inclined manometer as shown:
PRESSURE SWITCH
INCLINED
MANOMETER
1/4" COPPER TEE
HOSE
TO J-TUBE
Reconnect wires VT-18 to Common and YL-11 to NO ter-
minals.
With Power ON:
WARNING
LINE VOLTAGE NOW PRESENT.
4. Energize furnace for heating cycle. The induced draft
blower motor will begin to run. The inclined manometer
should read approximately 1.35" W.C. negative on small
cabinets units and approximately 3.50" W.C. negative
on large cabinets with no combustion. Refer to the Prod-
uct Design section for pressure tap location.
5. Remove and check the two electrical wires and using
the VOM check from Common to NO (Normally Open),
it should read closed (with I.D. motor running). If not as
above, replace control.
6. Reconnect all wires to the control and place in heating
cycle.
7. As the unit fires, the inclined manometer negative pres-
sure will drop to -.90" W.C. for the small cabinets and -
1.90" W.C. for the large cabinets.
8. Begin to restrict the flue outlet until the pressure control
trips, cycling OFF the burner. The control will trip at
approximately 0.36" W.C.negative.
9. If not as listed, replace control.
Note: the pressure switch must be mounted with the dia-
phragm in a vertical position.
S-311 HIGH ALTITUDE APPLICATION
Package units covered by this manual are approved for
use to 6,000 ft. in the USA. Canada (CSA) certified units
are approved for use to 4,500 ft. High altitude kits provide
for operation to 11,000 ft. in the USA. High altitude kits are
not approved for use in Canada. It is not necessary to
change the pressure switch for high altitude operation.
GAS
Kit
Number
Altitude
(Feet)
Orifice
NATURAL HANG07 6001 - 11000 # 45
L. P. GAS HALP09 6001 - 11000 # 56
S-312 CHECKING HOT SURFACE IGNITER
"Smart Valve" systems use a silicone carbide restrictive el-
ement ignitor is used for ignition. The normal operating tem-
perature is approximately 2550°F. "DSI" systems use a
spark type igniter.
WARNING
Disconnect Electrical Power Supply:
1. Ignitor cool - approximately 70 - 75°F.
2. Disconnect the ignitor from the Ignition Control Module
and line voltage terminal board.
3. Using an ohmmeter measure the resistance of the igni-
tor it should read between 16 to 24 ohms for Norton
mini ignitors. DSI system do not use hot surface igni-
tors.
4. Reconnect igniter.
With Power ON:
WARNING
VOLTAGE NOW PRESENT.
5. Place unit in heating cycle, measure current draw of
ignitor during preheat cycle. Should read approximately
1 to 1.5 amps.
S-313 TESTING IGNITION CONTROL MODULE
NOTE: Failure to earth ground the unit, reversing the neu-
tral and hot wire connection to the line (polarity), or a high
resistance connection in the ground or neutral lines may
cause the control to lockout due to failure to flame sense.
WARNING
To avoid the risk of electrical shock, wiring to the unit
must be properly polarized and grounded. Disconnect
power before performing service.
The ground wire must run from the furnace all the way back
to the electrical panel. Proper grounding can be confirmed
by disconnecting the electrical power and measuring resis-
tance between the neutral (white) connection and the burner
closest to the flame sensor. Resistance should be less
than 10 ohms.
Honeywell Smart Valve Ignition Systems
NORMAL SEQUENCE OF OPERATION (Honeywell
Smart Valve System)