Heat recovery is a ventilation system that employs a counter-flow heat exchanger between the inbound and outbound air flow. HRV provides fresh air and improved climate control, while also saving energy by reducing the heating requirements.
The Set Up
Stale moist air will be extracted from the ‘wet areas’ of the home, these are generally bathrooms, Utility rooms and Kitchen. Before this warm stale air is dumped outside it passes through the heat exchanger which will transfer it’s heat to the new fresh air, the tempered fresh air is then piped into the living areas of the home.
The Installation
First of all a unit location must be decided, this is generally the loft space or a press (one thing to remember is that access will be required at the unit for cleaning / changing filters 3-4 times a year).
Once this is decided next is the ceiling diffuser positions. We use ceiling valves for this, the supply valves are designed in a way that the air is thrown across the ceiling to prevent draughts and for better air dispersion.
Next is to connect and duct the the unit, the unit has four 150mm DIA spigots:
- Exhaust – The stale air is exhausted to outside VIA a roof cowl or via a external louvre on a gable wall
- Intake – Fresh air is taken into the house again VIA a roof cowl or an external louvre on a gable wall
- Supply Air- A 150mm pipe will be connected to a manifold plenum box from here a pipe semi rigid PVC pipe will run to each living area room (bedrooms, living rooms, dining room etc.)
- Extract Air – A 150mm pipe will be connected to a manifold plenum box from here a pipe semi rigid PVC pipe will run to each wet room (kitchen, utility, bathrooms and WC)
Once all ducting – plumbing (there is a condensate drain off the unit) and electrics are installed and connected the unit will then be commissioned to achieve a balanced air flow. The air flows are determined based on the size, occupancy and design of the house.
The benefits of HRV
As building efficiency is improved with insulation and weatherproofing, buildings are intentionally made more air-tight, and consequentially less well ventilated. Since all buildings require a source of fresh air, the need for HRVs has become obvious. While opening a window does provide ventilation, the building’s heat and humidity will then be lost which is undesirable for the indoor climate and for energy efficiency. HRV technology offers an optimal solution: fresh air, better climate control and energy efficiency.
Health In The Home
The rise of the asthma epidemic can be traced back to the oil crisis in the mid-seventies, the effect of which was a drive for energy efficiency. Increasing levels of insulation, combined with double-glazing and the sealing of buildings, dramatically reduced domestic ventilation rates, which in turn produced warm, humid and polluted indoor environments. Such conditions proved ideal for the colonisation and proliferation of the house dust mite. The need for HRV in the home has become obvious.
Energy Efficiency
All HRV’s we install are SAP appendix Q elegible and use low energy DC motors to ensure the running costs are kept to a minumum.
Construction
When designing your home It is important to allow for the installation of HRV to ensure the system will be as efficient as it should be.
Air Tightness
Air tightness is the elimination of all unwanted draughts through the fabric of the building envelope through the proper installation of an airtight membrane. As a result condensation, mould, rot and damp are eliminated ensuring a more viable building with an insulation layer performing properly, reducing the Co2 emissions from the building and making your home more energy efficient and cheaper to maintain.
The Key Benefits of Airtightness:
- Airtightness maximises the effectiveness of thermal insulation giving you massive savings over its lifetime
- Airtightness reduces Co2 emissions dramatically. Only a reduction in Co2 can mitigate the greenhouse effect
- Reduces heating costs and the use of fossil fuels which are damaging to the atmosphere
- The inclusion of airtightness is included in revisions to the building regulations
- Airtightness is vital when using the Heat Recovery System
Retro-Fit
Retro fitting a HRV in your home is possible in many cases, where access is available to the rooms from the attic or void spaces. to see if your home can be retro-fit contact us. Please also see our single room heat recovery units which can be easily installed into existing dwellings.
Insulation
This is vital for the comfort of your home please visit keating insulation or contact us for more information on different solutions
