RECOfrost
A patented, smart adaptive defrosting function for GOLD PX units with counterflow heat exchanger. In cold weather and when the extract air is humid, there's a risk of frost formation, which can reduce efficiency and airflow. RECOfrost automatically detects these conditions and adjusts operation to prevent frost buildup, ensuring reliable performance and energy efficiency even in challenging climates.
Why should you activate it?
As days get colder and winter approaches, counterflow (plate) heat exchangers face a serious challenge: frost. The reason is purely physical, the more heat you recover, combined with high indoor humidity, the colder the exhaust air becomes. This leads to condensation, and soon after, frost. Even at just a few degrees below zero, ice begins to form. The higher the energy efficiency and indoor humidity, the greater the risk of icing.
That’s why all plate heat exchangers need defrost controls to operate reliably in cold conditions. Without it, ice can build up inside the exchanger, reducing airflow, increasing fan energy use and lowering heat recovery efficiency. Traditional defrosting methods use fixed cycles to open and close the bypass dampers, allowing cold outdoor air to bypass the heat exchanger. Unfortunately, this often happens on the days when you need heat recovery the most, typically the coldest days, which also tend to have the highest energy prices. These methods waste energy and result in high energy bills, since you need to reheat a large portion of the supply air before releasing it into the building.
RECOfrost solves this by using adaptive control to monitor real conditions and only defrost when necessary. This ensures stable comfort, reliable operation, and optimised energy performance throughout the year —even in harsh climates.
Main benefits
RECOfrost delivers three things that matter most: low energy costs, comfort and sustainable buildings. By minimising unnecessary bypassing of air, it will keep the supply air temperature stable during defrosting and protect your system from frost damage.
The key benefits are:
- Outstanding energy efficiency: It minimizes defrosting cycle times and pressure drops, saving fan energy.
- Stable comfort: Maintains supply air temperature during defrosting, reducing post-heating.
- Reliability: Protects your system from frost damage and ensures continuous operation.
- Smart seasonal mode: In spring and autumn, RECOfrost opens dampers to reduce pressure drop, saving up to 64% in fan energy.
- Patented and exclusive: RECOfrost is a unique, sensor-driven control included in every Swegon GOLD PX unit.
This function is ideal for buildings in cold climates or projects with strict energy targets. RECOfrost is patented and always included in the Swegon GOLD control system, free of charge - making it unique on the market.
The Swegon RECOfrost function was the winner of the BeBo “Bättre Bostads-FTX” technology competition, funded by the Swedish Energy Agency in 2024.
How does it work?
RECOfrost combines adaptive section defrosting and bypass regulation.
This is how it works:
• It monitors pressure drop, outdoor temperature, extract air temperature, and humidity.
• When frost risk is detected, the system activates section-by-section defrosting using bypass dampers and airflow control.
• The bypass function maintains the same supply airflow during defrosting, so comfort is never compromised.
• Defrosting cycles are adjusted based on real-time conditions.
• Opens dampers in spring and autumn when full energy recovery isn’t needed, reducing pressure drop and saving fan energy.
Everything is automatic and fully integrated — no manual intervention or extra hardware required.