From inside (document excerpt):
Pressure Switch Kit Cancels: New IIK 352M-60-5 5-03 Installation Instructions Part No. 328529-751 NOTE: Read the entire instruction manual before starting the installation. SAFETY CONSIDERATIONS Installing and servicing of 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. Follow all safety codes. Wear safety glasses and work gloves. Have 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 word DANGER, WARNING, CAUTION, and NOTE. These words are used with the safety-alert symbol. DANGER identifies the most serious hazards which 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 pressure switch kit contains the following items: Pressure Switch Assembly (HK06NB013 High Pressure Switch (labeled make point = 1.81 in. w.c. max. break point = 1.58 in. w.c. min. Low Pressure Switch (labeled “Collector Box “) make point = 1.06 in. w.c. max. break point = .91 in. ± .05 in. w.c. Tubing Assembly, 7.88 ” (319873722) Tube, 12.5 ” Installation Instructions INSTALLATION Step 1–Removal of Old Pressure Switch Assembly 1. Turn off gas and electrical supplies to furnace. 2. Remove furnace door. 3. Disconnect wires from pressure switch. 4. Remove pressure tubes from pressure switch. 5. Remove pressure switch assembly from inducer housing. Step 2–Modify High-Pressure Switch Tubing Assembly 1. Remove high-pressure switch tubing assembly from collector box. 2. Replace old high-pressure switch tubing assembly with kitsupplied tubing assembly 319873-722. If servicing a 4 or 5-cell unit (080 or 100 size), cut tube from stock length (7.88) to 7. Step 3–Modify Low-Pressure Switch Tubing Assembly Turn off gas and electrical supplies to unit before beginning any installation or modification. Failure to follow this warning could result in personal injury or death. INTRODUCTION This instruction covers the installation of the pressure switch kit Part No. 328529-751 in all two-stage condensing gas furnaces. DESCRIPTION AND USAGE This pressure switch kit is designed for use when replacement of the factory-installed pressure switch is required. This kit is for use with models 352MAV and 58MTA.