Spa Components 4.0kW [15" x 2"] FloThru Heater [PS/TI] [Brett Aqualine] (B24040E) grundfos A tube like this is

A tube like this is useful because it helps transmit the pressure condition to the related control component

A pressure switch is useful because it helps verify proper system conditions before the heater continues operating

Useful when replacing a failed or unreliable original relay

Useful when original transformers have failed or become unreliable

10" round grate

Spa Components 4.0kW [15" x 2"] FloThru Heater [PS/TI] [Brett Aqualine] (B24040E) grundfos A tube like this isThe Spa Components 4. 0 kW flo thru heater is designed for compatible 2 inch by 15 inch heating applications associated with Brett style systems and a PS TI configuration. Flo thru heaters are useful because they provide direct in line heating while preserving the plumbing path and heater layout the spa system was built around. This replacement is especially useful when the original heater no longer produces dependable heat, has failed electrically,