HHT AK4 Outside Air Kit for Majestic & Monessen Fireplaces

Improve Fireplace Efficiency with Dedicated Outside Combustion Air

Boost fireplace performance with the HHT AK4 Outside Air Kit, delivering outside combustion air for improved efficiency and cleaner operation.

Key Features

• Genuine HHT AK4 outside air kit for fireplaces
• Designed for Majestic and Monessen vent-free fireboxes
• Enhances combustion efficiency and burn performance
• Reduces negative pressure in airtight homes
• Helps improve indoor air quality and comfort
• Compatible with a wide range of fireplace models
• Durable construction for long-term reliability

Product Features

Direct Outside Combustion Air Supply

The HHT AK4 outside air kit supplies fresh air directly from outdoors, reducing reliance on indoor air and improving fireplace efficiency—ideal for modern, energy-efficient homes.

Improves Fireplace Performance

By providing consistent airflow, this outside combustion air kit helps maintain a steady flame, improves fuel efficiency, and supports optimal fireplace operation.

Reduces Negative Air Pressure

Prevents drafts and pressure imbalances commonly found in tightly sealed homes, making it an essential fireplace air kit accessory.

Wide Compatibility with Majestic & Monessen Fireplaces

Engineered for use with numerous vent-free fireboxes and fireplace systems, ensuring seamless installation and performance.

Flexible Installation Options

• Can be installed through exterior walls, crawl spaces, or basements
• Supports multiple installation configurations for different home layouts
• Works with standard 4-inch ducting (sold separately)

Durable OEM Construction

Manufactured by Hearth & Home Technologies, ensuring high-quality materials and long-lasting performance in demanding heating environments.

Supports Cleaner Indoor Air

Helps reduce indoor air depletion and improves comfort by introducing fresh outside air for combustion.

Compatible Fireplace Models

Can be installed on:

BUF Series Fireboxes

• BUF400 – 36" Circulating Firebox with Radiant Cleanface
• BUF500 – 42" Circulating Firebox with Radiant Cleanface

GCUF Series Fireboxes

• GCUF32C-F, GCUF32C-R
• GCUF36C-F, GCUF36C-R
• GCUF42C-F, GCUF42C-R

GRUF Series Fireboxes

• GRUF32C-F, GRUF32C-R
• GRUF36C-F, GRUF36C-R
• GRUF42C-F, GRUF42C-R

Lo-Rider Series Fireboxes

• LCUF32-R, LCUF32CR-B
• LCUF36C-R, LCUF36CR-B
• LCUF42CR-B
• LPF36 (Peninsula)
• LSTF36, LSTF36-B (See-Thru)

Magnum Series Fireboxes

• MCUF36D-R, MCUF36E-F
• MCUF42D-R, MCUF42E-F

Vent-Free Fireplace Systems (VFF Series)

• VFF32CNI, VFF32CNV, VFF32CPI, VFF32CPV
• VFF32LNI, VFF32LNV, VFF32LPI, VFF32LPV
• VFF36CNI, VFF36CNV, VFF36CPI, VFF36CPV
• VFF36LNI, VFF36LNV, VFF36LPI, VFF36LPV

Product Specifications