4 Reasons The SolarVenti Is Better Than a Heat Recovery System

For those unfamiliar, a Heat Recovery  System (HR) is fan system that lives in your roof space. It blows the hot air in the roof space and pumps it into the room below. The box may say it removes mould, damp whilst also heating and cooling your home but its effectiveness could be better.

A SolarVenti lives on the roof and it sucks in fresh, outdoor air. Heats it, dehumidifies it, filters it and the pumps it into your home.


An easy comparison is the filter. The HR system lives in your roof space. So it needs to filter the dirty roof space air before it pumps it into your home. Unfortunately, this filter needs to be replaced regularly and adds to the ongoing costs of the unit.

A SolarVenti unit, however, lives on the roof. It sucks in the fresh air from outdoors. And it filters the fresh air. The benefit of this is that the SolarVenti filter will never need to be replaced. Making the SolarVenti the only no-running-cost solution. 


The HR system plugs into your home's ac power, running up your power bill. The SolarVenti and our Whirlybirds are solar powered. So through the day, your unit isn't using any of your electricity - running for free. Optionally, if you need the system running through the night, you can plug it up to a battery or plug it in to your own home's outlet.


Lifehacker (2015) confirmed that sucking hot air out is more effective than trying to push outdoor, cool air in.

A HR proposes that it can pump the "cold night air" inside your home on humid and hot nights. The roof space throughout the day heats up to 60°C – 70°C. So it may take some time for the HR to start cooling the home. HR users have to wait for the unit to first pump all this heated air into the home until the eaves vents provide the cooler, night  air.

When it comes to cooling, we recommend a holistic ventilation solution that follows Lifehacker's negative pressure ventilation advice.

A much better solution for cooling your home would be to put a solar-powered whirlybird on your roof. What this does is that it exhausts the hot, dirty air in your roof and vents it to the outside - cooling the home all day (and night with a connection to mains power).

For additional cooling, we'd recommend installing ducted vents in the roof of each room. This will suck the rising hot, humid air up through the roof space and put pressure on your windows to suck in cool, fresh air. 

For those asthma and allergen sufferers who are sensitive to opened windows through the night, complement this ventilation solution with a Solarventi. A Solarventi lives on top of your roof, not in the roof space. So it's best equipped to pump filtered, dehumidified, cold night air into your home.

This solution keeps your home cool at any time of the day. Not like a HR which only cools at night.

Heating & Dehumidification

The heating effect of the HR is somewhat overstated. A HR unit simply fans the warm, musky, roof space air into your home - it doesn't do anything to actually heat the air. The SolarVenti solution lives outside the roof space, harnessing the sun to actually warm the air that it's circulating.

The HR' heat in the day/cool in the night solution doesn't work all year round. Our SolarVenti units pump heat into home during the day and cooling at night as well. However, we recommend the SolarWhiz solution for cooling and a bio-ethanol fireplace for real heating.

So what are these systems good for? What are we  chasing?

These ventilation systems are good for dehumidification. We want comfort in our homes not an arbitrary temperature. 24°C can feel like 30°C on a humid day. Additionally, a 8°C with 80% humidity can feel like 4°C.

Humidity makes warm days feel warmer, and cold days feel colder. Moreover, high levels of humidity are breeding conditions for mould and other allergens.

The SolarVenti works to dehumidify and warm the fresh air it's pumping into the home. Whilst the HR merely pumps in the air that it is in the roof space. The act of ventilation itself (air changes in the home/replacing air) dries out the home but only the SolarVenti takes this effect further, drying the air before it pumps into your home - keeping humidity at bay.


I hope this gives a glimpse into why we believe the SolarVenti is the best ventilation product on the market. Get in touch with us, one of our technicians will happily walk you through it.

Please note: Commercial SolarVenti units are much larger and are designed to dry products (clothes, wheat) throughout the day. They actually heat rooms with the competitiveness of air conditioners. Not simply dehumidify (and day heating) like the residential range.