The Pentair MasterTemp Tubesheet/Coil Kit (77707-0232) is the OEM replacement heat exchanger assembly for the Pentair MasterTemp pool and spa heater line. ⚠️ IMPORTANT: HEATER COMPONENT — PROFESSIONAL SERVICE REQUIREDGas 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 tubesheet and coil assembly is the core heat transfer component inside the MasterTemp heater. Pool or spa water circulates through the coil while combustion gases pass over the exterior surfaces, transferring heat into the water. Failure of this assembly — through scaling, corrosion, or physical cracking — results in loss of heating capacity or water leakage into the combustion chamber. Replacement restores the heater's designed thermal output and protects downstream components from water contamination damage. Specifications Pentair Part Number 77707-0232 Equipment Line Pentair MasterTemp Part Type Tubesheet / Coil Kit Verify against your heater's installation manual or the part number stamped on the original assembly before ordering. Poolaroo Pro Tip Before ordering, locate the model number and BTU rating on your MasterTemp heater's rating label — typically found on the side or rear of the unit. MasterTemp heaters are available in multiple BTU configurations (200K, 250K, 300K, 400K, and 460K), and tubesheet/coil assemblies are not universally interchangeable across all BTU variants. Confirm that 77707-0232 matches the part number on your existing assembly or is listed in your specific heater model's parts breakdown before purchasing.
