420020007S Control Board Kit Replacement and Upgrade for Pool and Spa Heaters Key benefits Direct compatibility with a wide range of MasterTemp and MaxETherm heater control boards, making replacement straightforward. Improved reliability through upgraded components and protective coatings that extend service life in humid environments. More stable power delivery to the main control system, reducing the chance of electrical faults and improving overall heater performance. What this kit includes and how it performs Replacement control board model 420020007S designed for direct fit and function with specified heater controllers. Includes 472610Z switch membrane pad. Constructed on quality FR4 copper foil laminated board for stable signal routing and mechanical strength. Upgraded solidstate capacitors and precision welding improve electrical reliability and reduce component failure. SR waterproof coating enhances resistance to moisture and provides improved insulation and leak protection. Each control board undergoes usage testing, quality inspection, and aging tests prior to shipment to verify function. Upgraded power module Uses quality filtering capacitors and an LM2576HVS switching power chip to provide a stable DC supply for the main control electronics. The upgraded power stage improves conversion efficiency and helps maintain consistent operation under varying electrical conditions. Compatibility Compatible with Pentair MasterTemp NA and LP series pool and spa heater electrical systems, including: MasterTemp 200 control board MasterTemp 250 control board MasterTemp 300 control board MasterTemp 400 control board MasterTemp 400HD control board Also compatible with StaRite MaxETherm models: SR200NA control board SR333NA control board SE400NA control board SR200HD control board SR333HD control board SR400HD control board Practical use scenarios a failed control board on a MasterTemp heater that displays error codes or will not ignite, restoring normal operation. Upgrade a control board in a unit exposed to humidity or splash to reduce repeated failures from moisture intrusion. Keep a replacement board on hand for service technicians performing field repairs on the listed heater models to minimize downtime. Why choose this kit Designed to match original control board form and function while using improved components for greater durability. Thoroughly tested before shipment to help ensure reliable, plugin replacement performance. Clear compatibility with specific MasterTemp and MaxETherm control board models simplifies selection. Note Verify that your heater control board model matches one of the listed compatible models before ordering.