Recent Blog Posts

Condenser Relief Valves

January 7th, 2025

Question: Are pressure relief valves required to be installed on an evaporative condenser? This is an update to a blog that was originally posted on 9/10/13. You can read the original blog here. Answer: This is a very good question and one that gets asked frequently. Since an evaporative condenser is not a pressure vessel, […]

Ammonia Release | Relief Valve Termination (High Pressure Receiver)

December 10th, 2024

Summary In July 2017, the termination of a relief valve to the atmosphere resulted in a release of approximately 1,500 lbs of ammonia, and four personnel injuries. Proper operating procedures were not followed during a seasonal startup of the ammonia system. Several mistakes were made which resulted in the high pressure receiver overpressurizing, and the […]

Ammonia Refrigeration Valve Tags

November 26th, 2024

This is an update to a blog that was originally posted on 10/4/16. You can read the original blog here. When reviewing an ammonia refrigeration Piping and Instrumentation Diagram (P&ID) and comparing it to the actual refrigeration system, I am often surprised at how often valves have not been physically labeled to match the P&ID. […]

Ammonia Release | Pinhole Leak

November 12th, 2024

Summary In September 2016, the development of a small hole in the wall of an ammonia suction pipe resulted in a release of 15 lbs of ammonia. Neglected insulation breaches allowed moisture to accumulate on carbon steel piping. This resulted in corrosion and eventually, a pinhole developed in the wall of the pipe.  Release Calculation […]

Ammonia Refrigeration System Oil Draining Requirements

October 29th, 2024

Ammonia refrigeration systems must be equipped with a means of draining oil from the system. Over time, small amounts of oil are carried out of the compressors and mix with the ammonia vapor. The ideal place to collect and drain this oil is on the low pressure side of the refrigeration system. The cold temperatures […]