Air Source Heat Pump (ASHP)

Air Source Heat Pump (ASHP)

An Air Source Heat Pump is an alternative to a standard gas boiler; it takes heat from the air outside your property and converts it to energy to heat your radiators and hot water.

It is vital the air source heat pump is never switched off as it may have to be reset by a certified operative and you may be recharged for this.

An air source heat pump (ASHP) works on a hot water priority system, this means if your heating is on and someone within the household has a shower or bath the heating will temporarily switch off whilst the hot water is used.

The water cylinder stores the hot water at the pre-set temperature. If a lot of the hot water is used at once it may take around an hour to reheat the water in the cylinder.

The radiators or underfloor heating in your home won’t feel as hot as a standard gas central heating system as the ASHP system is designed to run for longer periods but at a lower temperature as it will continue to maintain the heat. This may be different to previous heating systems you have used so you may need to adjust your previous habits in order to get the best out of this system.

The controls for the heating and hot water are usually in a cupboard and will be pre-set to suit most households. You can adjust the timing schedules if you need to or turn down the temperature in the summer. If you have radiators the temperature can be adjusted in each room using the thermostatic radiator valve (TRV). The most efficient way to use the system is to set the thermostat to a fairly consistent temperature all the time. Please refer to the instruction booklet provided for how to make any adjustments.

Once a week an automatic system will initiate to kill harmful bacteria, where the water heats up to 60 degrees for 5 minutes. This is a legal requirement so cannot be switched off, and is usually set to run during the night.

It is important the ASHP unit outside is not moved or covered to allow airflow and enable the system to operate efficiently.

Don’t lean anything against the unit outside (for example a bike)
Don’t hide it behind a screen
Don’t put anything on top of the unit
Ensure you clear away any surrounding leaves.

If there is a power cut the heating system will turn off and the connection will be lost between the heat pump and the indoor control unit. When the power is restored the heat pump and the indoor control unit will turn back on and should automatically re-establish connection with each other after several minutes.

In the event that the connection is not re-established automatically, a fault code will appear on the indoor control unit and the system will need re-connecting manually. You can refer to the user manual, which was provided to you in your welcome pack for further instructions on trouble shooting, but generally you will be able to establish the connection by following the instructions below:

You will firstly need to reset the system. To do this you will need to turn off the switch on the wall in the cupboard where the indoor control unit is located. Then find the red rotary switch which should be on the wall close to the heat pump outside your home and turn this to the off position.
Wait 2 or 3 minutes before switching the indoor unit back on followed by switching on the heat pump outside.
The system will take a further few minutes to fully switch back on, it should then automatically re-establish the connection between the heat pump and indoor control unit and the fault code will disappear.
If the heat pump has been off for a long time due to continued loss of power then it may take some time to heat the stored water back up to operational temperature before it can start heating your home and providing hot water again.

Condensation on the unit outside is normal and which may result in a small pool of water under the unit. In cold weather a defrost cycle will occasionally kick-in to avoid the system freezing.

Please note, it is vital the air source heat pump is never switched off as it may have to be reset by a certified operative and you may be recharged for this.

The system should be serviced once a year by a qualified operative. If you have an ASHP in your property you will have received a more in depth leaflet or a QR barcode which you can scan to access a user manual. If you require further assistance please contact us on 01296 732600.

6 top tips on making the most of the heat pump:

Keep the heat pump thermostat at a fairly consistent temperature throughout the winter to avoid over-working the heat pump. You can set the temperature a little lower at night and a little higher during the day, and use the TRVs to keep some rooms a bit warmer than others, but the more constant the temperature the better. Between 18 and 21C is ideal – the heat pump can warm your home more than this but will use more energy. Lower temperatures are not recommended as they can increase the risk of damp and mould.
Search around for the best tariff as you may find heat pump-specific electricity tariffs that save you money. More energy suppliers are now providing a range of energy tariffs to suit individual household needs. It’s worth shopping around on price comparison sites to find the best one for you.
Raise any issues right away. If you have any problems with your heat pump, see any warnings on the control screen, or need further advice on using the system, please get in touch. It’s best to fix problems quickly so that you don’t risk going without heating and hot water.
Use your smart meter’s in home display to keep track of how much energy you are using.
Fit radiator reflector panels behind any radiators on external walls, to keep more heat in the room.
Get the app for your heat pump, if there is one.

Heat Pump myth busting from Carbon Brief: 6 common myths and the reality

Heat pumps don’t work when it’s cold
- Heat pumps can work at temperatures well below freezing.
- Their widespread popularity across Scandinavia is evidence that they can operate in much colder weather than we typically get in the UK!
- While the efficiency at very low temperatures will be a little lower, studies show that heat pump efficiency at sub-zero temperatures is typically still double the efficiency of gas boilers.
- At low temperatures the defrost cycle will kick in to avoid the outdoor system freezing up.
Heat pumps require a lot of maintenance
- Heat pumps don’t require any more maintenance than a gas boiler.
- There aren’t a lot of moving parts in a heat pump and the system is fairly simple, so as long as they are used correctly and serviced regularly they should be no more prone to breakdowns and should have just as long a life, if not longer.
- If anything doesn’t seem right with your heat pump though please get in touch immediately so we can sort it.
My home won’t be kept warm
- When correctly designed and installed, heat pumps can be just as good as fossil fuel systems at keeping your home warm and comfortable, if not more so.
- A study by Nesta found that over 80% of households with heat pumps were satisfied with its ability to provide space heating and hot water.
Heat pumps only work with underfloor heating
- While they work well with underfloor heating, heat pumps perform very well with radiators too.
- Radiators often need to be fairly large for the heat pump to run efficiently. Careful calculations are done when the system is being designed to ensure the radiators are sized correctly for the property and the system performs as well as it can.
Heat pumps are a new, untested technology
- Surprisingly enough, heat pumps as a technology have actually been around for over 150 years! And they first started being installed in people’s homes decades ago
- While the heat pump market has expanded rapidly recently and new models have been coming to market, the underlying technology is well established and understood.
- As demand grows, manufacturers are constantly on the lookout for ways to make heat pumps more efficient, smaller and quieter, and also simpler to install and maintain.
Heat pumps are too loud
- Air source heat pumps do make some noise, from the spinning of the fan in the outdoor unit while they are running
- But there are strict noise limits on heat pumps in the UK and the latest models are pretty quiet
- The noise volume is comparable to that of an oil boiler or fridge-freezer.

Air Source Heat Pump video transcript

Hello and welcome. This video is to help you use and make the most out of your air source heat pump that's been installed in your property.

It's vital that your air source heat pump is never switched off, it's designed to be continuously on and that is the most efficient way of using it. It's vital that if you do turn it off that a trained operative comes to turn it back on, you could be recharged if this is the case.

The air source heat pump transfers air from the outside via a heat exchanger inside this unit that is used to heat the water for your hot water and your heating inside the property. Taking air from the outside allows it to be four times more efficient than other electric heating sources. For every one unit of electricity used it produces four units of heat, this means it reduces the electricity use and is really good for the planet which means you're doing your bit.

Your air source heat pump works on a hot water priority system. That means when your heating is on if someone decides to have a shower or bath the heating will kick off temporarily and the hot water will kick in.

Your hot water cylinder is located in the area covered just like this. If you do use all of your hot water or the majority of it, it will take around about an hour for it to fill up and get back to the preset temperature.

The radiators in your home will never feel as warm as they would with a standard gas central heating system. This is because an air source heat pump is designed to be on for longer periods and be more efficient running at lower temperatures. This will mean that it will take a little longer for the temperature to get up to the actual setting that you've put on the thermostat but don't worry your home will still be cozy and warm and you'll still feel the benefits once the heating system is up and running.

It's worth being aware of the differences I've just mentioned so that you get the best results from your heating in your home.

The controls for your heating and hot water will usually be inside the boiler cupboard and will be preset to suit the needs of most households. This is also where you can adjust the settings or if you need to turn down the temperature in the summer, but really all the standard day-to-day tasks can be controlled via the thermostat. This includes changing the temperature and setting up schedules so when the heating comes on and goes off.

It's important to remember that you should be setting the thermostat to a temperature you would find comfortable throughout the day as leaving the system at a set temperature is the most economic and efficient way to run it. It is often recommended that setting the temperature to a constant 19° tends to suit the needs of most people.

Please refer to the instruction booklet provided for how to make any adjustments. If you have radiators, the temperature can be adjusted in each room individually using the thermostatic radiator valve or TRV.

It's very important that your air source heat pump is not moved or covered, this will help it work in the most efficient and effective way. Please don't lean anything up against it or especially cover the vent at the front.

You might find a pool of water that comes up underneath, this is perfectly normal and nothing to worry about, it's just condensation from the unit.

When we get to the winter as well, there's also a defrost cycle that kicks in so there's nothing to worry about about the system freezing outside when the temperatures drop.

After experiencing a power cut, you may find that the system stops working and will often show a fault code. This basically means that the outside unit has lost communication with the indoor unit. This can be fixed by resetting the communications between the two units. To do this, first switch off the power to the indoor unit using the switch on the wall and then switch off the power to the outdoor unit using the red rotary switch mounted on the wall near the unit. After turning both units off, you'll need to wait 2 to 3 minutes then turn the indoor unit back on first and then the outdoor unit afterwards. Wait a few minutes for the system to boot up and reconnect communications and the fault should be cleared. If the power is off for a long period, the heat pump will need to warm up before it can heat your home again so you may need to wait until the water has reheated.

The system will automatically initiate in order to kill bacteria. This will mean that the water is heated up to 60° and will last around about 5 minutes. This is a legal requirement and you have nothing to do and nothing to touch for this. the settings are already there for it to happen automatically, it will happen overnight so you won't even notice.

Your air source heat pump should be serviced by a qualified operative at least once a year.

Thank you for watching, I hope you find it interesting. If you do need more information please go to our website www.fairhive.co.uk/environment or refer to your information pack or alternatively, you can call us on 01296 732600.

Search the Fairhive website