Product Overview

Restore the heating performance of a compatible Pentair or Sta-Rite pool heater with the Pentair 77707-0244 Cupro-Nickel Tube Sheet Coil Assembly Kit. This genuine OEM heat exchanger assembly is specifically designed for select 400,000 BTU Heavy-Duty MasterTemp and Max-E-Therm heaters manufactured before January 12, 2009.

The 77707-0244 is built with durable cupro-nickel construction, making it an excellent replacement for demanding pool and spa heating applications. The tube sheet and coil assembly transfers heat produced by the burner into the circulating pool or spa water. Over time, improper water chemistry, freeze damage, scaling, corrosion, or normal wear can cause the original heat exchanger to leak or lose efficiency.

Replacing a damaged tube sheet assembly can restore proper water containment and heat transfer without requiring replacement of the complete heater.

Key Features

• Genuine Pentair / Sta-Rite OEM replacement
• Manufacturer Part Number: 77707-0244
• Designed for 400,000 BTU Heavy-Duty heaters
• Cupro-nickel heat exchanger construction
• Fits compatible Pentair MasterTemp 400HDNA
• Fits compatible Pentair MasterTemp 400HD-LP
• Fits compatible Sta-Rite Max-E-Therm 400 HD Series
• For heaters manufactured BEFORE 1/12/2009
• Original tube-design replacement assembly
• Designed for natural gas and propane HD configurations where specified
• Includes required tube-sheet sealing components
• Professional heater installation recommended

Product Specifications

Compatible Heater Models

The Pentair 77707-0244 is specified for compatible:

Pentair MasterTemp

• 400HDNA – 400K BTU Heavy Duty Natural Gas
• 400HD-LP – 400K BTU Heavy Duty Propane

Sta-Rite Max-E-Therm

• SR400 HD / compatible 400 HD Series models

Pentair's replacement-parts documentation lists 77707-0244 for the original 400HD tube design and 474065 for heaters manufactured after 1/12/2009.

What's Included

Pentair's parts documentation identifies the tube-sheet coil kits as including the necessary sealing and related service components, including O-rings, insulation, igniter and blower gaskets. Package contents can vary with production revision, so the current factory packaging should be verified when exact individual components are required.

Important Compatibility Notice

Do not order this heat exchanger based only on the heater's 400K BTU rating.

The manufacturing date is critical.

• Before 1/12/2009: Use 77707-0244
• After 1/12/2009: Pentair lists 474065 for the newer tube design

Check the heater data plate, model number, serial number, fuel type, and manufacturing date before ordering.

Why Cupro-Nickel?

Cupro-nickel heat exchangers provide strong heat-transfer performance with increased resistance to demanding water conditions compared with standard copper applications. They are commonly used in Heavy-Duty heater configurations where additional durability is desired.

Proper pool chemistry is still essential. Low pH, excessive sanitizer levels, incorrect flow, scale buildup, or improperly installed chemical feeders can damage any heat exchanger.

Frequently Asked Questions

What does Pentair 77707-0244 fit?

It fits compatible MasterTemp 400HDNA, 400HD-LP and Sta-Rite Max-E-Therm 400 HD heaters manufactured before January 12, 2009.

Is this the cupro-nickel version?

Yes. 77707-0244 is the Heavy-Duty cupro-nickel tube sheet/coil assembly.

What part do I need for a 400HD made after 1/12/2009?

Pentair lists 474065 for compatible 400HD heaters using the newer tube design after that date.

Is this a genuine Pentair part?

Yes. 77707-0244 is a genuine Pentair / Sta-Rite OEM replacement component.

Should this be professionally installed?

Yes. Pool-heater heat exchanger replacement involves gas, electrical, combustion, and plumbing systems and should be performed by a qualified heater technician.