4 Reasons The SolarVenti Is Better Than a Heat Recovery System

For those unfamiliar, a Heat Recovery System (HRS) is fan system that lives in your roof space. It blows the hot air from the roof space and pumps it into the rooms below. The box may say it removes mould and damp whilst also heating and cooling your home but its efficiency is reliant on how badly your roof is insulated (for heat) and normal outside air (for cooling). What is does not do is eliminate gases or fumes that originate in your roof space like Radon, toxin pest powders or any air borne bacterias from vermin.

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


An easy comparison is the filter. The HRS lives in your roof space. So it needs to filter the dirty roof space air before it pumps it into your home. Unfortunately, this ventilation filter also 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. With its patented design the benefit of this is that the SolarVenti filter will never need to be replaced. Making the SolarVenti the only no-running-cost filtrated ventilation solution. 


The HRS 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 HRS 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. As the ducting runs through your roof space, it may take some time for the HRS to start cooling the home. HRS 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 extraction or negative pressure ventilation advice.

A much better solution for cooling your home would be to put a solar-powered roof ventilation fan on your roof. What this does is that it exhausts the hot, dirty humid 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 suggest installing ducted diffusers in the ceiling 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, we advocate this ventilation solution with a Solarventi. A Solarventi pushes genuine dehumidified, filtrated fresh air into the home. So it's best equipped to pump filtered, dehumidified, cold night air into your home as well.

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

Heating & Dehumidification

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

 The SolarVenti units pumps heated air into your home during the day and with a cooling option, cooling at night as well. 

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, an 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 perfect 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 HRS merely pumps in the air that it is in the roof space, if your tastic or toilet/shower fans expel their moist steamy air into your roof void, then this is the air that will go into your home. The act of ventilation itself (air changes in the home/replacing air) dries out the home relative to its incoming air (intake air) 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 ventilation units are much larger and are designed to dry products (grains, fruit, wheat, bio mass, bio waste etc) throughout the day.  With good thermal absorbing materials, a complete system can manage night drying also.