Product Overview

The Sta-Rite Max-E-Therm SR400HD is a 400,000 BTU natural gas high-performance pool and spa heater designed for fast heat-up, dependable operation, and heavy-duty residential pool heating applications. Built by Pentair, the Max-E-Therm HD model delivers powerful heating performance in a compact, lightweight design with a corrosion-resistant exterior housing.

This natural gas heater is ideal for pools and spas that need strong heating output, quick temperature recovery, and reliable performance in demanding equipment pad environments.

Ideal For

Pool and spa owners needing a powerful 400,000 BTU natural gas heater for larger pools, attached spas, seasonal heating, or replacement of an existing Sta-Rite, Pentair, or compatible gas heater setup.

Key Features

400,000 BTU natural gas pool and spa heater

HD high-performance model

120/240 VAC electrical compatibility

60 Hz operation

Compact and lightweight equipment pad design

Digital control panel for easy temperature adjustment

Self-diagnostic controls for service and troubleshooting

Corrosion-resistant Dura-Glas exterior housing

Designed for pool and spa heating applications

Low NOx certified design

Professional installation recommended

Benefits

The Sta-Rite Max-E-Therm SR400HD provides strong 400K BTU heating performance for customers who want fast pool or spa heat-up times. The compact cabinet design makes it easier to fit on crowded equipment pads, while the digital controls and diagnostic features help simplify operation and service.

The HD model is built for dependable performance and is a strong choice for customers replacing an older heater or upgrading to a high-output natural gas pool heater.

Specifications

Warranty & Compatibility

Confirm Before Ordering

Please confirm fuel type, BTU size, gas line sizing, electrical requirements, plumbing layout, local code requirements, and installation location before ordering. This model is natural gas and is not the propane version. Professional installation by a qualified pool heater technician or licensed gas professional is strongly recommended.

Customer-Facing Q&A

Q: Is the SR400HD natural gas or propane?
A: The SR400HD is the natural gas version.

Q: How many BTUs is this heater?
A: This model is rated at 400,000 BTU.

Q: What does HD mean on this model?
A: HD refers to the heavy-duty / high-performance version of the Max-E-Therm heater line.

Q: Can this heater be used for both pools and spas?
A: Yes. This heater is designed for pool and spa heating applications.

Q: What electrical service does this heater use?
A: This model is listed for 120/240 VAC, 60 Hz operation.

Q: Does this heater have digital controls?
A: Yes. The Max-E-Therm series includes a digital control panel with diagnostic features.

Q: Does this require professional installation?
A: Yes. Gas pool heaters should be installed by a qualified pool professional or licensed gas technician.