Instruction manual

Fixed Speed Furnace Control
Replacement Kit
Installation Instructions
Part No. CESO110057-02
NOTE: Read the entire instruction manual before starting the
installation.
SAFETY CONSIDERATIONS
Installing and servicing heating equipment can be hazardous due to
gas and electrical components. Only trained personnel should
install or service heating equipment.
Untrained personnel can perform basic maintenance functions
such as cleaning coils, or cleaning and replacing filters. All other
operations should be performed by trained service personnel.
When working on heating equipment, observe precautions in the
literature, on tags, and on labels attached to the unit.
Understand the signal words DANGER, WARNING, and CAU-
TION. These words are used with the safety-alert symbol. DAN-
GER identifies the most serious hazards which will result in severe
personal injury or death. WARNING signifies a hazard which
could result in personal injury or death. CAUTION is used to
identify unsafe practices which would result in minor personal
injury or product and property damage. NOTE is used to highlight
suggestions which will result in enhanced installation, reliability,
or operation.
The ability to properly perform service on this equipment
requires certain expertise, mechanical skills, tools, and equip-
ment. If you do not possess these, do not attempt to perform
any service on this equipment other than those procedures
recommended in the User’s Manual. A failure to follow this
warning could result in possible damage to this equipment,
serious personal injury, or death.
INTRODUCTION
Circuit board Part No. CESO110057-02 is a direct replacement for
circuit boards Part No. CESO110057, CESO110057-01,
CESO110057, CESO110048, CESO110020, and HH84AA016.
This revised circuit board has incorporated LED diagnostics as an
aid in troubleshooting. It is recommended that a sight glass (not
included) be installed in a convenient location on the furnace, see
Optional Section. If a sight glass is not installed, the self-test
feature of the board can still be used for routine troubleshooting.
The fault code label provided must be installed on the furnace.
Major changes to the operation of this control include:
1. A 90 sec blower on delay if power is restored during a call for
heat.
2. The ignitor warm-up time is fixed at 17 sec.
3. The furnace will recycle if pressure switch opens and re-closes
during a call for heat.
4. If limit switch opens 4 times during a call for heat, circuit
board will lockout the furnace for 3 hr before resetting.
5. Blower off delay jumper has been replaced with DIP switches.
6. The inducer will run continuously during the self-test cycle.
7. Nominal flame sensing current is between 4.0 to 5.0 micro-
amps (uA) DC.
On twinned furnace applications, the CESO110057-02 board will
work with any of the above listed circuit boards and a
CESO110005 twinning control module.
NOTE: On twinned applications, the short jumper wire between
pins ST-2 and 225 MUST be removed from remaining circuit
board. Failure to do so will result in incorrect ignitor warm up
times and nuisance furnace lockouts.
ELECTROSTATIC DISCHARGE (ESD) PRECAUTIONS
CAUTION: Electrostatic discharge can affect electronic com-
ponents. Take precautions during furnace installation and
servicing to protect the furnace electronic control. Precautions
will prevent electrostatic discharges from personnel and hand
tools which are held during the procedure. These precautions
will help to avoid exposing the control to electrostatic
discharge by discharging static electricity build-up to ground.
1. Disconnect all power to the furnace. DO NOT TOUCH THE
CONTROL OR ANY WIRE CONNECTED TO THE CON-
TROL PRIOR TO DISCHARGING YOUR BODY’S ELEC-
TROSTATIC CHARGE TO GROUND.
2. Ground yourself by touching your hand and tools to clean,
unpainted, metal surface of furnace. close to control.
3. After touching chassis, you may proceed to service the
furnace. You will recharge your body with static electricity by
moving about or shuffle your feet. Reground yourself.
4. If you touch ungrounded objects (recharge your body with
static electricity), reground yourself. Use this procedure for
installed and uninstalled (ungrounded) furnaces.
5. Ground yourself again before handling a new control to
protect control from damage. If control is to be installed in
furnace, follow items 1 through 5 again before installing
control. Put all used AND new controls into containers before
touching ungrounded objects.
6. An ESD service kit (available from commercial sources) may
also be used to prevent ESD damage.
Step 1—Removal of Existing Control
Label all wires prior to disconnection when servicing con-
trols. Wiring errors can cause improper and dangerous
operation.
1. Turn thermostat to OFF or set temperature to the lowest
setting.
Cancels: New IIK 349M-50-1
9-98
Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obligations.
Book 1 4
Tab 6a 8a
PC 101 Catalog No. 535-715 Printed in U.S.A. Form 58DHC-6SI Pg 1 9-98 Replaces: New