From inside (document excerpt):
Variable-Capacity Furnace Replacement Control Center Kit Cancels: IIK 320A-60-10 IIK 320A-60-11 6-98 Installation Instructions Part No. 320729-752 NOTE: Read the entire instruction manual before starting the installation. This symbol indicates a change since the last issue. 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 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. Follow all safety codes. Wear safety glasses and work gloves. Have a fire extinguisher available. Recognize safety information. This is the safety-alert symbol. When you see this symbol on the furnace and in instructions or manuals, be alert to the potential for personal injury. Understand the signal words DANGER, WARNING, and CAUTION. These words are used with the safety-alert symbol. DANGER 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. 2. Firmly touch a clean, unpainted, metal surface of the furnace chassis which is close to the control. Tools held in a person’s hand during grounding will be satisfactorily discharged. 3. After touching the chassis you may proceed to service the control or connecting wires as long as you do nothing that recharges your body with static electricity (for example; DO NOT move or shuffle your feet, DO NOT touch ungrounded objects, etc.). 4. If you touch ungrounded objects (recharge your body with static electricity), firmly touch furnace again before touching control or wires. 5. Use this procedure for installed and uninstalled (ungrounded) furnaces. 6. Before removing a new control from its container, discharge your body’s electrostatic charge to ground to protect the control from damage. If the control is to be installed in a furnace, follow items 1 through 5 before bringing the control or yourself into contact with the furnace. Put all used AND new controls into containers before touching ungrounded objects. 7. An ESD service kit (available from commercial sources) may also be used to prevent ESD damage. INTRODUCTION This instruction covers installation of the variable-capacity furnace replacement control center kit Part No. 320729-752 in ALL variable-capacity furnaces regardless of their ignition type, intermittent spark ignition (IID) or hot surface ignition (HSI), or previous control center type. See Table 1 for kit contents. Turn off gas and electrical supplies to unit before beginning any installation or modification. Follow operating instructions on label attached to furnace. Failure to follow this warning could result in personal injury or death. ELECTROSTATIC DISCHARGE (ESD) PRECAUTIONS Table 1–Kit Contents DESCRIPTION PART NO. QUANTITY Harness 318843-401 1 Label Wiring 322296-101 1 Label Wiring 322297-101 1 Label Diagnostic 321223-101 1 Screw No. 6D X 1/2-in. LG 4 Wire Tie HY76TB125 2 Control Center HK42FZ012 1 2-Sided Adhesive Tape 34410B160 1 Installation Instructions IIK 320A-60-11/58M-57SI 1 Electrostatic discharge can affect electronic components. 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.