Carrier 58PB - Page 16

HEATING A COOLING
58ED,PB
Horizontal Gas-Fired Furnaces
Cleaning Heat Exchanger and Venting System
— The heat exchanger and venting system should be
checked each year by a qualified dealer. If necessary,
the following procedures should be performed:
1. Make sure that all utilities are turned off upstream
of the furnace (both gas and electrical supplies).
2. Remove burner covers, manifold assembly with
burners, vent connectors and draft hood.
3. Clean flue box, flue ways, burner box and burners
with brush and/or vacuum cleaner.
4. After cleaning, check pilot for proper position.
Replace all parts.
5. T urn on gas and electrical supplies. Test for leaks
using soap and water solution.
A CAUTION
Never use an open flame when testing for gas
leaks. Use a soap and water solution.
6. C h eck for proper operation of all controls.
Table 7 — Trouble Analysis Chart for Standing Pilot Models
A WARNING
Turn off gas and electrical supplies to furnace before servicing. (Unless specific
test requires gas and electrical supplies )
SYMPTOM AND PROBABLE CAUSE
REMEDY
BURNERS WILL NOT IGNITE
1 Pilot light out
1 Relight pilot If pilot does not remain lit, replace
thermocouple
2 No 115-v power to furnace j
2. Connect to power supply. Check fuse, wiring or circuit
breaker.
3 No 24-v power to control circuit
3. Check transformer; replace.
4. Miswired or loose connections
4 Check all wiring and wirenut connections.
5. No gas at main burners
5 Check to see if main valve is operating Look for loose or
broken wiring connections If no deficiency is found, replace
valve assembly.
6 Flame probe or connecting lead is shorted or open
6. Correct electrical shorting or open circuit
INADEQUATE HEATING
1 Furnace undersized for application
1 Replace with proper size furnace
2 Gas input to furnace too low
2. Check gas pressure at manifold. Clock gas meter for input
If too low, increase manifold pressure, or replace with correct
orifices.
3 Limit switch cycles main burners
3 OFF setting of fan control set too high; reset.
Dirty air filters; clean and reinstall.
Blower speed too low; use faster speed tap
Registers closed, restricted ductwork, open or remove
restriction
Check heat anticipator setting on thermostat, readjust.
ALDEHYDE ODORS (CO), SOOTING FLAME,
FLOATING FLAME
1 Incomplete combustion — poor flame characteristics
1 Air shutter on burners closed, adjust to soft, blue flame.
Check all screws aroundflueoutletsand burner compartment,
tighten
Lack of combustion air, see Installation section
Cracked heat exchanger; replace
Overfired furnace; reduce input or change orifices.
Check vent for restriction; clean as required
Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obligations.
BookII 1 4 PC101 Catalog No 535-834 Printed in U S A Form58ED,PB-1SI Pg 16 6-85 Replaces: 58PB-1SI
Tab 16a 18a For replacement items use Carrier Specified Parts.