Engine Room Cool Down For The Opal Lady A Nordhavn 43

November 23, 2021

Brad Marsden

Director - Marine Air Flow International

35 Years Experience in the Marine Industry

View Brad's Info

43 Nordhavn Overheating Challenges

It was an absolute pleasure to work with Peter, Suz and Neon the cat, to help them reduce the engine room temperatures in their Nordhavn 43.


Peter has been very active in his efforts to decrease operating engine room temperatures in his and Suz's boat the "Opal Lady" and has over the years added extra axial fans to help reduce consistant +50 degree (c) temps. Unfortunately Peters best efforts were not helping on longer runs and he contacted us on advice from a friend in May of this year.


The Opal Ladys original intake air grille

After inspection of the Opal Lady we discovered that despite Peter's amazing efforts, the amount of air moving through their engine room just wasn't sufficient. Opal Lady's air exchange sat at around 300 Litres per second and by our calculations the preferable amount was 870 Litres per second.


We don't just consider the combustion requirement for air supply, we also take into account your operating conditions (tropical or hot Vs cooler locations), whether you have wet or dry exhausts, the actual layout of your engine room and of course other components that could be using air and adding to the heat stress of the space.

The New Engine Room Ventilation System

After assessing all the factors that affect your engine room air flow and heating, we recommended the following system for Peter and Suz Nordhavn 43.



The Installation & Testing

Peter has been very glowing in the blog post on his website of how easy it was to install the system, and we are of course very appreciative of Peters comments.


While we don't install any of our equipment ourselves, each item is supplied with full installation instructions and everything you need to complete the installation. Peter installed everything himself, engaging an electricion to complete the wiring for him.


After leaving Sanctuary Cove and some base testing, Peter, Suz and Neon did a 2 and a half day trip to test the results. Without the new fans in an external temperature of 23 degrees celcius, they saw engine room temps of 46 deg C, however after turning the new fans on they had the following results.



  • At half speed the temperature dropped to 40 degrees
  • At Full speed the temperature dropped further to 33 degrees &
  • At three quater speed the temperature sat at a very maintainable 36 degrees.


Long term Peter ended up removing the extra Axial fan he had left on the port side of the engine room with no ill effects.

The Opal Lady
The manual fan speed controllers installed
The intake grille installed
By Brad Marsden June 10, 2025
Optimising Engine Room Ventilation for Abu Dhabi’s High-Speed Ro-Pax Ferries As part of Abu Dhabi’s ongoing investment in advanced maritime infrastructure, the AD Ports Group commissioned two high-speed Ro-Ro ferries to operate between the UAE mainland and Delma Island. Carrying 250 passengers and 25 cars per trip at a service speed of over 30 Knots is pretty impressive , and you'd have to agree they are certainly very tidy looking Roll On Roll Off Ferries!! Designed for both passenger comfort and operational performance, these cutting-edge vessels required a ventilation solution that could meet the rigorous demands of the Gulf’s climate and the intense operating conditions of four powerful MTU engines per vessel. Our team was proud to be selected to design and deliver the engine room ventilation system for these state-of-the-art ferries, ensuring they remain safe, efficient, and reliable at sea. Engineering the Future of Fast Ferry Travel Built to carry up to 194 passengers and 25 vehicles, each of the 56-metre-long catamarans has been equipped with four MTU 16V4000M65L high-performance engines driving Kongsberg KaMeWa waterjets. This powerful propulsion setup enables cruising speeds of up to 35 knots, making the ferries among the fastest in their class within the region. Inside, the vessels feature modern amenities such as a VIP lounge, children’s play area, two cafes, five toilets, and full wheelchair accessibility, highlighting AD Ports Group’s commitment to both efficiency and passenger experience. Operating in the heat of the Persian Gulf, however, presents unique engineering challenges. The heart of this lies within the engine room where temperatures, airflow, and safety systems must be tightly controlled to prevent overheating, ensure compliance, and protect both crew and machinery. A Tailored Ventilation Solution for Demanding Conditions The brief for this project was clear: create a ventilation system that could not only manage the extreme thermal loads generated by four high-output marine engines but also comply with international marine safety standards, including fire isolation and redundancy protocols. Key features of the system we delivered include: Marine-Grade Ventilation Dampers : Built from corrosion-resistant stainless steel, our dampers are designed for longevity and reliability in a saltwater environment. Integrated Auto Close Capability : The dampers are configured to close rapidly in the event of a fire, helping to isolate the engine room and restrict oxygen supply. High Airflow Capacity : Designed specifically for the compact, high-output layout of the engine rooms, the system allows for maximum airflow and heat dissipation under full load. Moisture and Salt Mist Defence: Our Intake grilles are known globally for their excellent capability of reducing salt mist and spray into your engine room. Here they allow a vessel operating in already extreme conditions to require far less ongoing equipment replacement. Redundancy & Safety : With automated control options and manual overrides, the system ensures continuous operation and safety during engine shutdowns or emergencies. Delivering Results at Sea With the ventilation system now fully installed and operational, the Ro-Pax ferries have successfully completed sea trials and are ready to begin service. The performance of the engine room ventilation under load has exceeded expectations, maintaining optimal operating temperatures even during high-speed runs in the peak Gulf heat. In addition to thermal performance, the system’s fire isolation capability offers an added layer of safety, helping these ferries meet stringent international compliance standards while delivering peace of mind for operators and passengers alike. Reflecting on the Project This project underscores the critical importance of high-performance ventilation systems in modern vessel design. From the intense thermal loads of multi-engine configurations to the need for rapid fire response and corrosion resistance, every detail matters when it comes to marine safety and reliability. We’re proud to have played a key role in supporting this milestone for AD Ports Group and Abu Dhabi’s maritime future and we look forward to bringing this level of engineering excellence to future vessel builds across the region and beyond. Talk to Us About Your Marine Ventilation Needs Whether you’re designing a new-build high-speed ferry or retrofitting an existing vessel, we offer tailored ventilation solutions that combine safety, efficiency, and performance. Get in touch with our team today to learn how we can support your next marine engineering project.
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