Product Overview

Complete a proper positive-pressure vent installation on a compatible Pentair or Sta-Rite pool heater with the Pentair 4" Stainless Steel Horizontal/Vertical Venting Adapter | 77707-0087.

This genuine Pentair OEM appliance adapter is designed for use with 4-inch Category III special gas venting and allows compatible pool and spa heaters to connect to a Z-Flex positive-pressure vent system.

Pentair part 77707-0087 can be used in either horizontal or vertical vent configurations, making it a critical component when installing a MasterTemp or Max-E-Therm heater in an application that requires mechanical positive-pressure venting.

The adapter installs at the heater's vent body and provides the proper transition between the heater exhaust outlet and the approved Z-Flex vent system.

Key Features

• Genuine Pentair OEM heater venting accessory

• Pentair part number: 77707-0087

• 4-inch vent connection

• Constructed from stainless steel

• Designed for positive-pressure venting

• Suitable for horizontal or vertical vent installations

• Intended for Category III special gas vent systems

• Designed specifically for Z-Flex / Z-Vent venting systems

• Fits compatible Pentair MasterTemp heaters

• Fits compatible Sta-Rite Max-E-Therm heaters

• Provides the required appliance connection between heater and vent system

• Suitable for indoor and specialized heater installations where approved positive-pressure venting is required

Specifications

Compatible Heater Families

Pentair 77707-0087 is designed for compatible:

• Pentair MasterTemp Pool & Spa Heaters

• Sta-Rite Max-E-Therm Pool & Spa Heaters

Compatibility depends on the heater model, BTU size, venting layout, installation environment, and applicable building and fuel-gas codes.

Always confirm the specific heater model and approved vent configuration before ordering.

What Does This Adapter Do?

MasterTemp and Max-E-Therm heaters can be configured for specialized Category III positive-pressure venting when the installation requires exhaust to be routed through approved vent piping.

The 77707-0087 adapter connects the heater's vent body to a compatible 4-inch Z-Flex vent system.

It may be used where the approved installation calls for:

• Horizontal exhaust venting

• Vertical exhaust venting

• Indoor heater installations

• Equipment rooms

• Enclosed installations

• Positive-pressure Category III vent systems

The venting system must still be engineered and installed according to the heater manual, vent manufacturer's instructions, local codes, and applicable fuel-gas standards.

Z-Flex Compatibility

Pentair specifically identifies 77707-0087 for use with Z-Vent / Z-Flex venting.

This distinction is important because Pentair also offers a separate adapter for other vent manufacturers.

Pentair Vent Adapter Comparison

If your installation uses Z-Flex venting, 77707-0087 is the correct Pentair appliance adapter specified for that vent system.

Installation Information

Pentair specifies that the appliance adapter installs directly into the heater's vent body after the exterior vent cover is removed.

Installation requires:

1. Shut down the heater and allow it to cool completely.

2. Disconnect electrical power and gas supply as required.

3. Remove the heater's exterior vent cover.

4. Access the vent body.

5. Clean the mating surfaces according to Pentair instructions.

6. Install the appliance adapter into the heater vent body.

7. Secure and seal the adapter using the vent manufacturer's approved materials and procedures.

8. Connect the approved Category III vent piping.

9. Verify required clearances from combustible materials.

10. Inspect the entire vent system before returning the heater to service.

Only materials approved by the heater and vent manufacturer should be used.

Important Venting Requirements

Pentair specifies 4-inch special gas-approved Category III vent pipe for this application.

The vent installation must comply with:

• Heater installation instructions

• Vent manufacturer's installation instructions

• Local building codes

• Local mechanical codes

• Applicable fuel-gas codes

• Required clearances from combustible surfaces

• Maximum permitted vent lengths

• Allowable number of elbows and fittings

Maximum vent length can change depending on heater size, vent diameter, and number of elbows.

Never exceed the venting limitations specified by Pentair.

Positive-Pressure Venting Explained

Positive-pressure heater vent systems use the heater's combustion blower to force exhaust gases through the vent pipe.

Because the vent operates under positive pressure, all joints and connections must be properly sealed using venting components approved for that application.

This differs from traditional negative-pressure or natural-draft vent systems.

A standard metal flue collar should not be substituted for the approved Category III appliance adapter in a positive-pressure installation.

Stainless Steel Construction

The 77707-0087 is manufactured from stainless steel for use in high-temperature combustion exhaust applications.

Stainless construction provides:

• Resistance to heat

• Resistance to moisture

• Improved corrosion resistance

• Durability in combustion-gas environments

• Compatibility with approved stainless Category III vent systems

Professional Installation Recommended

Gas heater venting is a safety-critical installation.

Incorrect vent sizing, improper sealing, insufficient clearance, or the use of non-approved vent materials may create dangerous exhaust or carbon-monoxide conditions.

Pool Supply Depot strongly recommends installation by a qualified pool-heater, HVAC, or licensed gas professional familiar with Category III positive-pressure vent systems.

Always follow Pentair's current installation manual and all applicable local and national codes.

Frequently Asked Questions

What is Pentair 77707-0087?

Pentair 77707-0087 is a genuine stainless steel appliance adapter designed to connect compatible MasterTemp and Max-E-Therm heaters to a 4-inch Z-Flex Category III positive-pressure vent system.

Can it be used for horizontal venting?

Yes. Pentair specifies this adapter for horizontal or vertical positive-pressure venting.

Can it be used for vertical venting?

Yes. It can be used in an approved vertical Category III vent installation.

What size vent does it use?

The adapter is intended for a 4-inch special gas-approved Category III vent system.

Does it work with Z-Flex venting?

Yes. 77707-0087 is specifically identified by Pentair for Z-Flex / Z-Vent applications.

Is 77707-0087 the same as 77707-0086?

No.

• 77707-0087 is intended for Z-Flex / Z-Vent

• 77707-0086 is intended for Saf-T Vent / HeatFab-style systems

Always match the appliance adapter to the venting system being installed.

Does this fit MasterTemp heaters?

Yes, it is used with compatible Pentair MasterTemp heater installations requiring approved Category III positive-pressure venting.

Does it fit Max-E-Therm heaters?

Yes, it is also used with compatible Sta-Rite Max-E-Therm heaters.

Is the full vent pipe system included?

No. 77707-0087 is the appliance adapter only. Vent pipe, termination fittings, elbows, sealants, and other vent components are sold separately.

Important Safety Notice

Improper gas-heater venting can allow combustion gases, including carbon monoxide, to enter occupied areas.

Installation should be performed by a qualified professional and must comply with the heater manufacturer's instructions, the vent manufacturer's instructions, and all applicable local and national codes.

Do not combine the exhaust vent from multiple heaters into a common vent unless expressly permitted by the applicable equipment and code requirements.