Aira Indoor Unit Compact
Small but mighty, the Aira Indoor Unit Compact is not your typical hydrobox. While it manages water flow and gathers system information like other hydroboxes, it goes further by optimising your heat pump’s efficiency over time thanks to Aira Intelligence.
One of the slimmest on the market, the stylish Aira Indoor Unit Compact can be placed wherever suits your home best, whether that’s on display in the kitchen or tucked away in a cupboard where your old boiler used to be.
What's included in this system?
As well as an outdoor unit, the Aira Indoor Unit Compact is accompanied by a hot water cylinder and buffer tank, which can be positioned somewhere out of sight in a more spacious area, like the loft.
Outdoor unit
The outdoor unit draws in and extracts heat from the fresh air outside to heat your home and hot water.
Hot water cylinder
The hot water cylinder is where your hot water is heated, stored and distributed to your home’s taps and showers.
Buffer tank
The buffer tanks is where hot water for your radiators and underfloor heating system is stored.
Hot water cylinder
If you have chosen an Aira Indoor Unit Compact as your indoor unit, you'll need a hot water cylinder. This is where your hot water is heated, stored and distributed to your home’s taps and showers.
With sizes ranging from 150L to 300L there’s a hot water cylinder to match your home’s thirst for hot water.
Buffer tank
Available in 40 and 100 litres, the buffer tank is where hot water for your radiators and underfloor heating system is stored.
They make sure your heat pump and heating system get the correct flow rate, ensure defrost cycles happen securely and prevent system temperature changes from making knocking sounds.
They even improve the durability of your heat pump system by minimising the system's stop and restart sequences during low-demand months. This is why they’re included in all Aira installations.
 | ![Slimline hot water cylinder [150L]](/_next/image?url=%2Fproducts%2FAira_Hydrobox_Hot_Water_Slimline.jpg&w=3840&q=75) | ![Hot water cylinder [200L, 250L, 300L]](/_next/image?url=%2Fproducts%2FAira_Hydrobox_Hot_Water.jpg&w=3840&q=75) | ![Buffer tank[40L, 100L]](/_next/image?url=%2Fproducts%2FAira_BufferTank_100L.jpg&w=3840&q=75) | |
|---|---|---|---|---|
| Model | Aira Indoor Unit Compact | Slimline hot water cylinder [150L] | Hot water cylinder [200L, 250L, 300L] | Buffer tank[40L, 100L] |
| Description | Hydrobox | Hot water cylinder | Hot water cylinder | Buffer tank |
| Best suited for | 1-6 people | 1-4 people | 1-6 people | N/A |
| Tank size | N/A | 150L | 200L, 250L, 300L | 40L, 100L |
| Tank type | Stainless steel | Stainless steel | Stainless steel | Stainless steel |
| Insulation | N/A | Polyurethane | Polyurethane | Polyurethane |
| Max temp tank | N/A | 85°C | 85°C | 95°C |
| Dimensions (cm) (w/d/h) | 40x25x72 | 43x43x161 | 60x60x127, 60x60x154, 60x60x175 | 37.5x37.5x71.5, 37.5x37.5x155.5 |
| Energy efficiency class at 35°c (in combination with heat pump) | A+++ | C | B | N/A |
| Connecticity | Bluetooth, Wi-Fi, Thread, Ethernet, Cellular | N/A | N/A | N/A |
Aira Indoor Unit Compact
| Description | Hydrobox |
| Best suited for | 1-6 people |
| Tank size | N/A |
| Tank type | Stainless steel |
| Insulation | N/A |
| Max temp tank | N/A |
| Dimensions (cm) (w/d/h) | 40x25x72 |
| Energy efficiency class at 35°c (in combination with heat pump) | A+++ |
| Connecticity | Bluetooth, Wi-Fi, Thread, Ethernet, Cellular |
Slimline hot water cylinder [150L]
| Description | Hot water cylinder |
| Best suited for | 1-4 people |
| Tank size | 150L |
| Tank type | Stainless steel |
| Insulation | Polyurethane |
| Max temp tank | 85°C |
| Dimensions (cm) (w/d/h) | 43x43x161 |
| Energy efficiency class at 35°c (in combination with heat pump) | C |
| Connecticity | N/A |
Hot water cylinder [200L, 250L, 300L]
| Description | Hot water cylinder |
| Best suited for | 1-6 people |
| Tank size | 200L, 250L, 300L |
| Tank type | Stainless steel |
| Insulation | Polyurethane |
| Max temp tank | 85°C |
| Dimensions (cm) (w/d/h) | 60x60x127, 60x60x154, 60x60x175 |
| Energy efficiency class at 35°c (in combination with heat pump) | B |
| Connecticity | N/A |
Buffer tank[40L, 100L]
| Description | Buffer tank |
| Best suited for | N/A |
| Tank size | 40L, 100L |
| Tank type | Stainless steel |
| Insulation | Polyurethane |
| Max temp tank | 95°C |
| Dimensions (cm) (w/d/h) | 37.5x37.5x71.5, 37.5x37.5x155.5 |
| Energy efficiency class at 35°c (in combination with heat pump) | N/A |
| Connecticity | N/A |
Will the Aira indoor Unit Compact be installed in the same location as my current boiler?
During our free home energy assessment, a Clean Energy Expert (CEE) will discuss where your indoor unit will be fitted.
The Aira Indoor Unit Compact is designed to fit where your old boiler used to be. However, your CEE may locate a better location that may increase the efficiency of your system.
Why does the Aira Indoor Unit Compact need a hot water cylinder and buffer tank?
The Aira Indoor Unit Compact is about a quarter the size (75% smaller) of our 100L all-in-one indoor unit (Aira Indoor Unit) because it doesn’t have an internal hot water cylinder. It does, however, have a built-in immersion heater that can provide backup heating and hot water in emergencies.
Hot water for your home’s taps and showers is stored and distributed by a hot water cylinder, which is available in multiple sizes ranging from 150L to 300L. Hot water for your radiators and underfloor heating system is stored in a buffer tank, which is available in 40L and 100L.
Does the Aira Indoor Unit Compact store any water?
The Aira Indoor Unit Compact has a built-in immersion heater that can provide backup heating and hot water in emergencies.
Hot water for your taps and showers is stored in a hot water cylinder, while the water for your radiators or underfloor heating is kept in a buffer tank.
How hot will my tap water be with an Aira Heat Pump and Aira Indoor Unit Compact?
The hot water temperature inside your hot water cylinders is typically set to between 55°C and 60°C. This ensures the heat pump operates efficiently while maintaining its capacity. A safety valve is installed outside the unit to prevent scalding.
What is the maximum output temperature the heat pump can provide for my heating with the Aira Indoor Unit Compact?
Your Aira Heat Pump can provide heating system water up to 75°C. However, output temperatures – or flow temperatures – rarely need to be that high for efficient heating. In most homes, a lower flow temperature of around 35-55°C is more than sufficient to keep your home at a warm and comfortable temperature of between 18˚C and 22˚C.
If necessary, the system will automatically adjust to provide higher hot water temperatures to ensure your desired indoor temperature is maintained.
As part of the Aira Comfort Guarantee, our 15 Year Performance Guarantee promises a cosy indoor temperature between 18˚C-22˚C, even on the coldest day of the year (depending on the room and based on expected minimum temperatures). If not, we’ll come out to fix it at no extra cost.
Read our terms and conditions under “warranty” to learn more about our heat pump’s ability to maintain minimum indoor temperature.
How does the Aira Indoor Unit Compact protect your water from bacteria?
If you have an Aira Indoor Unit Compact, the same legionella prevention process that takes place in an Aira Indoor Unit takes place in your hot water cylinder.
Learn more about the Aira Heat Pump system
Aira Outdoor Unit
The Aira Outdoor Unit draws in and extracts heat from the fresh air outside to heat your home and hot water.
Aira Indoor Unit
An alternative to the Aira Indoor Unit Compact, the Aira Indoor Unit efficiently stores and distributes hot water to your home’s taps and showers.
Aira Home Energy app
The Aira Heat Pump takes pretty good care of itself. But you always have control of your system anywhere, anytime, with the Aira Home Energy app.
