SpecDirectory

CTD400

Burnham by U.S. Boiler · Commercial Boiler

ENERGY STAR CertifiedCommercial Boilers →
Thermal Efficiency

97%

Input Rate

399MBTU/hr

Turndown Ratio

9.00

Application

Indoor

Burnham by U.S. Boiler CTD400: thermal eff 97%, around the middle of the range for commercial boilers (category median 96.5%).

Where this model sits

Input399MBTU/hr
300median 7502500
Thermal Eff97%
94median 96.598.7

The Burnham by U.S. Boiler CTD400 is a 399 MBTU/hr commercial boiler. At 97 % it ranks around the middle of the 386 certified commercial boilers models. Among similar-sized commercial boilers (within 10% of its size), it is more efficient than the peer median of 96.5 %.

Specifications

Performance
Thermal Efficiency97%
Full-Load Input Rate399MBTU/hr
Turndown Ratio9.00
Configuration
ApplicationIndoor
Control TypeMulti-stage
Model NameCitadel
Identifiers
Model NumberCTD400
ENERGY STAR IDES_23449_CTD400_05112023171727_3118858
PartnerThermal Solutions Products LLC
Date Qualified2026-04-27
Available From2023-04-24
MarketsUnited States, Canada

Documentation

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