Flue Gas Recovery

Leading the industry in advanced clean-tech mechanical designs.

A proprietary arrangement of specialized heat exchangers, pumps, valves, dampers, controls and a draft inducer help reclaim the wasted heat energy generated by hot water heating boilers. Ambient air temperatures combined with incoming domestic water help fully condense and convert 100% of the available energy.

Objective

Design innovation to increase the efficiency of hot water heating boilers by reclaiming wasted thermal energy.

Key results

Carbon Cap developed a proprietary Flue Gas Recovery (FGR) system including a condensing economizer that provides two times the heat transfer over others. This resulted in greater boiler efficiency, less natural gas consumption and lower carbon emissions.

Technology Information

  1. Reclaims thermal energy normally lost by heating boilers.
  2. Easily retrofitted on hot water heating boilers.
  3. Tri-conservation system saves natural gas, electricity and water.
  4. Remote dashboard displays collected and realtime conservation information.
  5. Supports LEEDS and other green building certifications.
  6. Qualifies for natural gas and electric savings incentives where available.
  7. Can pre-heat or pre-cool make up air ventilation and air conditioning systems.

  1. Increases buildings asset valuation.
  2. Rapid payback (usually under 24 months, before incentives).
  3. Offsets carbon tax.

  1. Prolongs life of boilers (boilers reach set point sooner).
  2. Preheats incoming cold water and boosts temperature of boiler returns.
  3. Redirects waste heat from boilers to condensing economizer system.
  4. Provides greater redundancy by operating independently of existing boilers.
  5. Thermal energy is captured outside the boilers normal exhaust stream.
  6. System creates no back pressure on venting system.

  1. Installed by any licensed mechanical trade company with Carbon Cap certified training.
  2. All components easily transported through standard doorways.
  3. Will conform to all necessary regulatory approvals.

Case Studies

Real-World Results with the Flue Gas Recovery (FGR)

Description about result, impact or how we help our customer to achieve their goal.

Hands-On Innovation Mohawk College

Mohawk College partnered with Carbon Cap Inc. to support the automation and monitoring of its heat recovery system, helping boost boiler efficiency and cut emissions. Through hands-on collaboration, students and faculty developed the system’s automation, Human-Machine Interface, and remote monitoring tools. The project, funded by Ontario Centres of Excellence and Bloom, gave students real-world experience while advancing clean technology solutions.

Read Project

Read News

Mock Facility Testing

A Watershed technology report showed that Carbon Cap’s Flue Gas Recovery (FGR) system can cut natural gas use by 15–25% in multi-residential buildings by capturing waste heat from boiler exhaust. Tested on an atmospheric boiler, the system recovered nearly all flue gas energy using an air-to-water heat exchanger to preheat domestic hot water. Results confirm strong technical performance and highlight FGR’s potential as a cost-effective retrofit for improving boiler efficiency.

Read More

SAISS Technology Report

Carbon Cap’s Flue Gas Recovery (FGR) system cuts natural gas use by up to 24% in multi-residential buildings by capturing waste heat from boiler exhaust to preheat water or air. A Toronto pilot showed average savings of 14%, along with reduced emissions and recoverable water, making it a practical and efficient retrofit solution.

Read More

Full year results building deployment report

In continuous operation since February 2023, Carbon Cap’s FGR-10 system has proven to be an economical and effective retrofit for reducing natural gas use and emissions by capturing waste heat from boiler exhaust. A Toronto installation delivered an average 14% savings over 13 months, helping building operators lower energy costs and meet sustainability goals with minimal disruption.

Read More