Pentair 400K Heater Heat Exchanger Kit [After Jan 2009] (474061) kempusa A control system is useful

A control system is useful because it helps centralize spa operation

The 1-1/16 inch hole size helps define the intended shell fit

A complete unit can simplify installation and reduce the guesswork of rebuilding piece by piece

An air control helps homeowners fine tune the feel of a spa seat

Pentair 400K Heater Heat Exchanger Kit [After Jan 2009] (474061) kempusa A control system is usefulThe Pentair 400K Heater Heat Exchanger Kit [After Jan 2009] (474061) is a replacement heat exchanger kit for compatible 400,000 BTU Pentair heater models manufactured after January 2009. The heat exchanger is one of the most important components in a pool or spa heater, transferring heat from the combustion process to the water moving through the system. When a heat exchanger is leaking, restricted, corroded, or otherwise damaged, heater performance