Marine HVAC dry dock installation & system overhaul

A comprehensive case study of advanced port installation work. A professional marine HVAC dry dock installation completely renewed the AHU units for both port and starboard sides, guaranteeing reliable accommodation cooling.

Needs diagnosis and marine HVAC dry dock installation

Our team of experienced technicians executed an advanced retrofit project in a commercial port. The main objective of the service was a comprehensive marine HVAC dry dock installation on a cargo vessel, covering the main Air Handling Units (AHU) separately for Port & Starboard sides. The outdated system no longer met the requirements of modern navigation, leading to the decision for a complete replacement.

A properly functioning air conditioning system is essential for crew safety and hygiene during long voyages. Thanks to precise engineering planning, the entire task was completed without disrupting the vessel’s cargo handling schedule.

Specifics of marine installation work

Every professional marine HVAC dry dock installation requires adapting piping and automation to harsh oceanic conditions. Aggressive salt spray and hull vibrations mean all penetrations and mountings must strictly comply with guidelines officially set by the International Maritime Organization (IMO).

Detailed scope of mounting and technical work

Work began by constructing entirely new foundations under the AHUs for the refrigeration system. The core of the new system on each side was an efficient Frascold Z50-168Y compressor. New components installed included an RDYG 40 liquid receiver, oil separator, and suction accumulator. Two CJR-612424 air-cooled condensers were also installed on deck per side.

Such an advanced marine HVAC dry dock installation required precise pipe pre-fabrication. Hull penetrations were made for the piping, secured with certified Roxtec bulkhead transits. The system received a new electrical cabinet and controls: Danfoss KP 15 pressure switches (HP protection) and KP 5 (capacity and fan control).

• Danfoss refrigeration valves: GBC shut-off valves and NRV 35 check valves were installed on liquid and return lines.
• Filters and automation: 48 DM filter-driers, EVR 35 solenoid valves, and new TE 55 thermostatic expansion valves with nozzle #10 were fitted.

Pressure testing and commissioning parameters

The completed freon system underwent a rigorous 24-hour pressure leak test using nitrogen at 20 bar. Following successful verification, the system was evacuated to -1 bar and charged with 50 kg of R407C refrigerant.

Commissioning measurements confirmed flawless operation. Operating pressures were: suction 4.5 bar, discharge 14 bar, oil pressure 8.5 bar, and evaporation temperature reached +5°C. High-pressure protection (HP) tripped correctly at 22 bar. As per engineering practice, oil replacement in the compressors was recommended after approximately 24 hours of continuous operation. Looking for a trusted partner? Check our engineering competencies in HVAC-R design and refrigeration retrofits.