Product Overview

Condensing Boilers from 399 to

850 MBH

Condensing Water Heaters from

199 to 500 MBH

High Efficiency with Thermal

Efficiencies up to 97%

Compact Footprint

Modulating with 5 to 1

Turndown

Advanced Cascade Capability

Building Automation System Option

Features

Meets SCAQMD NOx Emissions

Requirements

High Efficiency Gas Boilers and Water Heaters

Keystone Series Condensing Boilers and

Water Heaters are designed for large residen-

tial and light commercial applications.

The stainless steel heat exchanger and

burner provides high efficiency, low emis-

sions, and a high turndown to minimize short

cycling. With maximum inputs of 850 MBH for

boilers and 500 MBH for water heaters, the

Keystone series can meet most needs with a

single unit.

For larger requirements the advanced control

allows units to be joined and function with

parallel modulation for maximum efficiency.

LP Conversion Kit

500 - 850 MBH

Boilers are

CSD-1 Compliant

STANDARD

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High Efficiency Gas Boilers and Water Heaters Keystone Series Condensing Boilers and Water Heaters are designed for large residential and light commercial applications. The stainless steel heat exchanger and burner provides high efficiency, low emissions, and a high turndown to minimize short cycling. With maximum inputs of 850 MBH for boilers and 500 MBH for water heaters, the Keystone series can meet most needs with a single unit.
PAGE 2
Technical Specifications 246 3" 4" 26"x 24 1/2" x 38” 276 3/4" KW 399 E 2" 3/4" 4" 4" 346 KW 500 E 2" 1" 4" 31"x 24 1/2" x 38” 4" 31"x 24 1/2" x 38” 381 1 1/4" 3/4" 4" 4" 31"x 24 1/2" x 38” 346 KS 500 E 1 1/2" 1" 4" 4" KS 600 E 1 1/2" 1" 4" 4" KS 750 E 2" 1 1/2" 4" 6" KS 850 E 2" 1 1/2" 4" 6" Model Boilers 26"x 24 1/2" x 38” 3" 4" 1/2" 2" KS 399 E Water Heaters Weight Lbs Vent Diameter 1 1/4" KW 199 E Water KW 285 E Heaters Boilers Dimensions DxWxH