The latest news and happenings from the Bonar Engineering team. Learn what sets us apart as the design/build specialist.

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Refrigerant Options for the Future


Air Unit Capacity

Dual Relief Valve Manifolds

Environmental Sustainability in Refrigerated Warehouses

Piston Expander-Linear Alternator

Compressor Lubrication Systems

Thermosyphon Oil Cooling Part 2

Thermosyphon Oil Cooling Part 1

Preventing Hydraulic Shock

Freezer Dock Doors

Surge Drums

Dock Levelers


Condenser Water Treatment

Preventing Ammonia Spills by Proper Design

Air Units and Hand Expansion Valves

Response to IIAR 2

Floor Expansion Joints

Freezing Systems


Desiccant Air Treatment

Comments Regarding IIAR Standard 2

Rules of Thumb for Machinery Room Design

Hank’s Rules of Thumb

Cold Storage v Dry Storage

The Truth About Oil Pots

Annular Flow

Air Changes in Refrigerated Spaces

BTUs and Refrigeration

Air Units and Pipeline Placement

Travels Through the Ukraine and Moldova

Box-in-a-Box Construction

Side Port Economizers

Ammonia Spill Cleanup Procedures

Tomato Ripening and an Article on Russian Refrigeration

A Brief History of Mechanical Refrigeration

Are All Screw Compressors Created Equal

Continuity of Vapor Barrier

Response to OSHA and a Refrigeration System

OSHA and an Ammonia Refrigeration System

Underfloor Heating Systems

Recirculated Vessel Design

Freon Rooftop Units v Central Refrigeration Systems

Critical Gas Flow




Posted on Tuesday, March 1st, 1994

On occasion we are asked about condenser piping. There are several misconceptions by some engineers and contractors passing about in our industry. Condensers have more “mystique” about them than any other portion of the refrigeration system. Understanding condensers necessitates understanding not only refrigeration thermodynamics, but also the psychometric relationships of water, water vapor, and water […]

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Posted on Sunday, March 1st, 1992

Shaft seals, a vital part of refrigeration systems, are both expensive to replace and costly to stock in case of seal failure. Bonar Engineering, Inc. is proud to announce the opening of its seal research lab facility. The lab incorporates factory training, state of the art equipment, failure analysis, quality control testing, a file to […]

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Mechanical Refrigeration: The Research Begins

Posted on Sunday, March 1st, 1992

The following is an excerpt from Industry in the Cold. prepared by the International Institute of Ammonia Refrigeration. Chicago, Illinois. The development of a thermometer by Galilei Galileo in 1597 marked the beginning of 300 years of research that led eventually to the modem mechanical refrigeration system. Early highlights of these experiments include the development […]

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Evaporative Condenser Maintenance

Posted on Sunday, March 1st, 1992

Bonar Engineering rarely recommends “post” chemical treatment of sanitary water make-up supplies for evaporative condensers. Municipal and private water supplies which have been treated with chlorine and the use of galvanized metal in the condenser will normally provide adequate “algae” control. We do recommend a bleed-off of at least 1/6 the evaporation rate of water […]

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System Component Design Review Compressor Selection

Posted on Sunday, March 1st, 1992

Compressor selection is probably the single greatest influence on power consumption costs in a refrigeration system design. With large numbers of competent “engineering contractors” providing refrigeration services to the industry, it is occasionally disenchanting to see competition “force” end users into purchasing systems which could easily carry a 10% to 15% operating cost penalty because […]

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