Air-source heat pumps have incredible advantages. Highly energy efficient, easy to install, no emissions. But what are the disadvantages of an air-source heat pump? To properly evaluate whether a heat pump is a good investment, we have to look long and hard at the disadvantages of air-source heat pumps.
Here’s what it lacks:
The benefits of using an air-source heat pump arguably outweigh their negative aspects. They can both heat and cool at an incredibly efficient rate.
Example: At -3 °C to 10 °C, many heat pumps run at a 3-3.5 coefficient of performance (COP). This means they generate 3 to 3.5 units of heat energy for every 1 unit of electricity consumed, significantly reducing your utility bills.
Still, there are downsides to overheating pumps as well.
in the middle ‘Domestic Renewable Heat Incentive’ Or ‘Clean heat grant’ For air-source heat pumps by the UK government, we have put together a list of all the cons of these heat pumps.
we will all see 8 Downsides of Air-Source Heat Pumps one in systematic Way. we’ll start with a high fixed price, and by all means follow the loss noise generation And dependence on electricity,
Here are the disadvantages of air-source heat pumps one by one:
1. High Upfront Cost (Biggest Downside)
Air-source heat pumps are very efficient to operate but they cost a lot of money to buy and install. High upfront cost is usually a major deterrent for homeowners looking to get one.
to illustrate: In the UK, a typical air-source heat pump can cost anywhere £5,000 to £12,000 . in between (with installation).
air-source heat pump prices £2,000 to £6,500, The unit cost (outdoor unit + indoor unit + refrigerant line) represents about 50% of the total cost. The other 50% is the installation cost; That mainly includes the labor cost to install an air-source heat pump.
The actual total price of an air-source heat pump installation in the UK depends primarily on:
- unit size.
- Number of indoor units (air handlers). 4-zone air-source heat pumps, for example, are more expensive than 2-zone air-source heat pumps.
- installation difficulty. To install a heat pump, an HVAC technician has to drill a hole in the wall for the refrigerant lines (these connect the outdoor unit to the indoor air blower).
While the initial heat pump investment may set you back a lot, it is advisable that you think about the air-source heat pump costs over a period of time. 10 or 20 years, Electricity is saved due to higher energy efficiency, which represents a negative initial cost of air-source heat pumps.
Green Match, an award-winning UK blog about renewable sources of energy, provides free estimates on the cost of air-source heat pumps. If you are interested in cost estimation, you can see Green Match Cost Estimate Calculator Here,
2. Air-source heat pumps provide less heat supply than boilers
If you are used to oil and gas boilers, you will find that air-to-air heating pumps provide less heat supply. This is a commonly cited disadvantage of air-source heat pumps.
With heat pumps, it is especially difficult to heat large homes, by extension, large rooms.
To solve this problem of air source heat pumps, you may need:
- Large indoor air handler.
- Large radiator. If you have to install additional radiators or replace existing radiators with larger radiators, there will be some upfront costs of re-installing a heat pump heating system.
- Underfloor heating system. Many air-source heat pumps work best with underfloor heating. Of course, if you don’t already have underfloor heating installed, you’ll need to have it installed to reap the benefits.
Insufficiently insulated homes will have problems with air-source heat pumps
The disadvantages of using an air-source heat pump in older UK homes are also evident. With the lower heat output of heat pumps compared to boilers, you will benefit from good insulation. This way the heat will accumulate most efficiently.
UK old houses Not having as good insulation can lead to lower temperatures in winter as a negative consequence of using air-source heat pumps.
Despite the negative – low overall temperature There is also a positive side to this. Indoor temperatures are much more consistent when you’re heating your home with an air-source heat pump.
3. Low efficiency in extreme cold weather
A known disadvantage of air-source heat pumps is their inability to heat efficiently at very low temperatures.
Most heat pumps can have up to 300% efficiency (3.0 COP value) even at −3 °C, according to Wikipedia, On top of that, in mild UK climates, these air-source heat pumps can reach up to 400% efficiency (4.0 COP value).
However, a negative effect occurs when the outside air temperature is well below the freezing point.
Due to the second law of thermodynamics, the efficiency of most air-source heat pumps will be drop to 100% (1.0 COP value) Around −18 °C. Feather, Below that temperature, heat pumps are rather inefficient because they can’t adequately handle outdoor/indoor temperatures.
This is a major con for using a ductless air-source heat pump in very cold environments. Fortunately, the United Kingdom has mild winters. You don’t see temperatures below -18°C in most places like London at all.
So this loss is not quite relevant in the UK. Also, the mild winters on the island are precisely why it makes a lot more sense to install an air-source heat pump in the UK than in Scandinavia or Canada, for example.
4. Short Lifespan (about 15 years)
What do air source heat pumps run for? about 15 years, It is quite tall but not as tall as a ground source heat pump; Whose life span is about 20 years.
The reason for the short lifetime of air-source heat pumps is easy to understand:
They exposure to environmental factors, The outdoor unit (with the compressor) is exposed to all kinds of dirt, twigs, leaves, grass, insects, variable temperatures, etc. This will cause more wear and tear than would be exposed to a ground-source heat pump.
Of course, you can extend the lifespan of an air-source heat pump by committing to annual servicing. However, this adds to the maintenance cost of air-source heat pumps, doesn’t it?
Adding maintenance costs on top of the initial cost is another downside of air-source heat pumps.
5. How noisy are air-source heat pumps? not the coolest
In the past, air-source heat pumps were quite noisy. With improvements in compressor technology, the noise level of modern heat pumps has reduced significantly compared to older units.
Dividing noise levels into two sections is the key to understanding how noisy air-source heat pumps are. Namely, we talk about the noise that the outdoor unit produces and the noise that the indoor air handler produces in the case of the Mini-Split Air-to-Air Heat Pump.
It is commonly said that air source heat pumps generate 40 to 60 dB of noise. This is only true for the outdoor unit. Here are the typical noise levels for both units:
- The noise level of the outdoor unit. This is a noisy part because it contains a compressor, and can generate anywhere from 40 to 60 dB. Example of noise level: 42/48/56 dB For low/mid/high speed setting.
- The noise level of the indoor unit. This is the quiet part of the house. Indoor air handlers generally generate much less noise than outdoor units; Even below 40 dB for all speed settings. The main noise generator is airflow generation; You can hear your indoor air handler blowing hot/cold air. Example of noise level: 29/32/36 dB For low/mid/high speed setting.
Overall, fast air-source heat pumps are a thing of the past. This was generally considered to be one of the main disadvantages of heat pumps.
Modern ductless heat pumps are much quieter. The part that really matters – the indoor air handlers in air-to-air heat pumps – generate less than 40 dB even at the high speed setting. The external unit containing the compressor may be a bit faster.
6. Dependence on electricity (power outage issue)
All heat pumps run on electricity. In normal times, this is not an issue. However, there are two major developments when reliance on electricity can be viewed as a disadvantage of the use of electric-powered air-source heat pumps.
- power cut. In the event of a power outage, your air-source heat pump will go out and your lights will go out as well. With the lights on, you can always light a candle. With a heat pump, most homes will not have an alternative heating or cooling source of sufficient size to replace the function of an air-source heat pump.
- Huge increase in electricity prices. Heat pumps use relatively little electricity compared to other electric-powered heaters (for example, 1500W space heaters) for the output they deliver. However, if electricity prices rise sharply, you will still be forced to use expensive electricity to run an air-source heat pump.
In such harsh events, having a home generator ready to generate electricity can be useful.
However, if you compare furnaces and stoves with heat pumps, heat pumps are at a disadvantage here because they run on electricity only, whereas furnaces and stoves run on liquid fuels (heating oil, natural gas, diesel) or hard fuels. Can walk on (wood). , pellets).
7. Planning Permissions to Install an Outdoor Heat Pump Unit (Wales, Northern Ireland)
No one really likes to deal with planning permissions. In some areas, you will need planning permission to install an air-source heat pump; Which causes a lot of damage.
Here are the current special planning permission requirements in the UK:
- in air-source heat pump Wales, You need to obtain planning permission to install a heat pump.
- in air-source heat pump northern england, You need to obtain planning permission to install a heat pump.
- in air-source heat pump England, In most cases, planning permissions are not required; It depends on the size and location of your home.
- in air-source heat pump Scotland, In most cases, planning permissions are not required; It depends on the size and location of your home.
For most UK homeowners, planning permissions are not required. However, if you live in an area where you must obtain specific planning permissions, you must meet the following requirements when installing an outdoor mini-split air-source heat pump:
- The outdoor unit must be installed at least 1 meter from the boundaries of your property,
- you have to use a heat pump for heating only (no cooling allowed),
- Flat surface installation. You must install the outdoor unit on flat ground or a flat roof.
- The total volume of the outdoor unit should not exceed 0.6 square meter3,
- if you live in conservation AreaYou are not allowed to install an air-source heat pump.
Many homeowners may be frustrated by the need for this planning permission. You will need to take care of this air-source heat pump problem before starting the installation.
It is advised that you check with your local offices what planning permissions you need. Depending on the requirements, you can choose the right size/position/installation for your heat pump.
8. Not the most flashy look
The ground-source heat pump or boiler is hidden from view. On the other hand, all air-source heat pumps require the external unit to be installed, well, outside.
This means you’ll have to deal with a huge (and often noisy) box on the outside of your home. It must be said that this is not the most attractive look.
This is another stumbling block of air-source heat pumps.
Overall, the advantages of heat pumps outweigh the disadvantages in most cases. However, it is important that you are aware of all the misconceptions about air-source heat pumps before installing one.
We hope this was helpful.