Pentair Air Pressure Switch | ETi® 400 & UltraTemp ETi® Heaters | 475987 Pool Pole Accessories restoring a proper pressure-tight seal

restoring a proper pressure-tight seal at the top of the filter tank

Blended indicator 1 drop = 10 ppm total alkalinity as CaCO₃ Hardness

O-49 Diffuser O-Ring

with no need for electronic controls

(4 × 80 sq

Pentair Air Pressure Switch | ETi® 400 & UltraTemp ETi® Heaters | 475987 Pool Pole Accessories restoring a proper pressure-tight sealThe Pentair Air Pressure Switch (475987) is the OEM replacement pressure switch for the ETi 400 and UltraTemp ETi series pool and spa heaters. IMPORTANT: HEATER COMPONENT PROFESSIONAL SERVICE REQUIRED Gas and electrical heater components must be serviced by a licensed pool professional or qualified HVAC technician. Do not attempt to service gas or high voltage components without proper certification. The air pressure switch monitors airflow through