If a heat recovery system is designed correctly, with a correctly sized unit that matches the size of your house, it will not be noisy.
The most common reason I’ve come across for noisy systems is that there are not enough outlets to spread the air flow throughout the house. Another reason might be that the unit is undersized, meaning the machine has to work harder to hit the desired flow rates.
When a system is undersized, by the homeowner or the installer, it is usually to keep the costs down. But the cheapest is not always the best, and choosing a low budget machine may lead to long term problems.
And no, heat recovery ventilation does not provide heating. I talk to many people who believe they don’t need a central heating system or any other form of heating, as they think that heat recovery will meet all their home heating needs.
This is incorrect. The purpose of the machine is to ventilate the house, not heat it. The heat recovery aspect just makes the machine more efficient.
To simplify, a heat recovery ventilation system works by extracting your home’s moist, stale air. Then, it recovers the usually lost heat from the extracted air and returns it to your home by preheating the clean, filtered fresh air.