Pentair Union PVC 2 in. | ThermalFlo HP Titanium / UltraTemp ETi | 473381

The Pentair Union PVC 2 in. (473381) is the OEM replacement union fitting for the ThermalFlo HP Titanium and UltraTemp ETi heat pump lines, providing a serviceable, leak-free plumbing connection at the equipment inlet or outlet.

⚠️ IMPORTANT: LUBRICATION REQUIRED — SOLD SEPARATELY
Always lubricate the included O-ring with a silicone-based lubricant before installation. We carry the Pentair R172351 Lifeguard® Silicone Lubricant — the OEM-matched product for Pentair equipment.

This 2-inch PVC union allows the heat pump to be disconnected from the plumbing system for service or replacement without cutting pipe. The integrated O-ring creates a watertight seal at the union joint. Replacing a cracked, warped, or leaking union restores system integrity and prevents water loss at the equipment pad.

Specifications

Fits Into

Compatibility is based on Pentair parts documentation and available OEM records. This is not an exhaustive list. For certainty, verify the part number in your equipment's manual or on the original part itself before ordering.

Pro Tip

Before reassembling the union, apply a thin, even coat of Pentair R172351 Lifeguard® Silicone Lubricant to the O-ring. This seats the ring evenly, prevents tearing under thread tension, and extends service life significantly. Never use petroleum-based products — they will degrade the O-ring and cause premature failure. If your existing union shows stress cracking or the O-ring groove is damaged, replace the full union assembly rather than the O-ring alone.