Air/Ground heat pumps and easing of 1 m rule.
By Telegraph - Amy Gibbons - 23 November 2023
Low take-up of grants led the Chancellor to end blanket restrictions on the installation of controversial devices “arbitrary” rule with the potential to force households to install heat pumps in the middle of their gardens is set to be scrapped by the Government.
Under the plans, buried in the detail of the Autumn Statement, people would no longer have to fit the devices at least one meter from neighboring properties.
Ministers say ditching the rule would help to “capitalize on the UK’s world-leading approach to decarbonizing the economy”.
Currently, planning regulations mean that to qualify for the Government’s £5,000 heat pump grant devices should be installed at least one meter (3.28ft) from any boundary wall.
The rule was originally put in place to mitigate concerns over the noise levels from older models. But critics have said it is “arbitrary” and “challenging” to follow.
The Government has now announced it will look at bringing in “new permitted development rights” to end the “blanket restriction”.
The Autumn Statement says ministers will “consult on introducing new permitted development rights to end the blanket restriction on heat pumps one meter from a property boundary in England”.
Together with other measures, this will help “reduce delays and capitalize on the UK’s world-leading approach to decarbonizing the economy”.
In March, The Telegraph reported that Liz Bentley, a meteorologist, had been put off installing a heat pump because she feared it could end up stuck in the middle of her narrow garden.
“It has been challenging to find something that fits,” she said. “I’m probably going to end up with a solution that’s not ideal for me.”
She added: “If it’s stuck in the middle of my lawn, then I think that probably will be the final thing that will prevent us from moving down this road. My outside space is important to me, and I don’t really want one of these systems stuck in the middle of my garden.”
The issue was raised by the House of Lords Environment and Climate Change Committee in a letter to ministers earlier this year, which warned that the Government’s £450 million heat pump subsidy scheme was failing because of low uptake.
Baroness Parminter, the baroness Parminter, the chairman of the committee, warned the one-meter mandate was making installations “more challenging in some circumstances”.
But Lord Callanan, the minister for energy efficiency, told the House of Lords that it was up to local authorities to decide how to interpret planning rules.
The Department for Department for Energy Security and Net Zero has been approached for comment.
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Heat Pump Buying Guide
Updated May 26, 2022
A heat pump heats and cools your home, functioning like a combined furnace and central air conditioner. Because they absorb and move ambient heat rather than burning fuel (or using energy-hungry electric resistance) to generate it, heat pumps are exceptionally energy-efficient and environmentally friendly compared with other home climate-control systems.
They’re powered by electricity, are relatively easy to install in many homes, and may save you money compared with other heating, ventilating, and air-conditioning systems, depending on where you live and other factors, such as the cost of electricity.
A heat pump won’t be the perfect system for every home, but the technology is worth considering any time you need to replace or upgrade part of your HVAC system.
This guide will help you find the right heat pump for your home, whether it’s a ducted system or a mini-split, and whether you’re looking to replace or supplement a traditional heating and cooling system or simply want to upgrade to a newer, more efficient heat pump. We’ll describe the features to look for and share tips on how to find a qualified installer. Plus, we offer advice on how to make the most of your heat pump once it’s installed.
Consumer Reports members can also view our heat pump ratings for the most reliable brands of ducted heat pumps and the brands with the highest owner satisfaction. Our ratings include 24 brands and are based on data from our member surveys covering more than 13,500 heat pumps in real-world use, installed between 2005 and 2021. We do not test or recommend specific heat pump models because the systems are highly customized to individual houses and climates.
How Does a Heat Pump Work?
The most common type of heat pump, called an air-source heat pump, works by absorbing heat from the air and moving it either from outdoors to indoors (in heating mode) or vice versa (in cooling mode). It’s the same way an air conditioner works, and in cooling mode, air-source heat pumps work identically to ACs. The two types of appliances look similar, are generally manufactured by the same companies, and use almost all the same parts. Heat pumps just have a few small differences that allow them to move heat in two directions, in and out.
Until relatively recently, air-source heat pumps were predominantly used only in the southern U.S., where they’re a natural fit for hot summers and mild winters. But the technology has improved, making air-source heat pumps a practical choice almost anywhere in the country—even in places with cold winters. As counterintuitive as it seems, there’s always some free heat energy in the air, even on frigid winter days. Today’s cold-climate heat pumps can efficiently collect that free heat and move it into your home.
Heat pumps offer a lower-carbon way to heat your home than other options, even if they run on electricity that’s mostly generated by fossil fuels. When they’re powered by renewable energy, whether that’s rooftop or community solar or a cleaner grid, they become even more sustainable. Because of their energy savings and environmental benefits, some states and utility companies offer rebates or other incentives to homeowners who install heat pumps.
You can use a heat pump as the sole heating and cooling appliance in your home, or you can combine a heat pump with an existing heating system. Many homes with existing ductwork for forced-air HVAC systems can be adapted to heat pumps. Ductless heat pump systems, called mini-splits, can provide heating and cooling in a home without ducts, or add climate control to rooms that the main system doesn’t reach.
Living with a heat pump is a bit different from using a traditional heating system. A modern heat pump is most efficient when your thermostat is set at a constant temperature—it actually saves energy if you don’t turn it down overnight. They also blow cooler air than furnaces and run almost constantly at a low level, rather than blasting heat for short periods throughout the day. Good insulation and air sealing of your home and duct system are important regardless of how you heat your home, but they’re even more beneficial with heat pumps.
Types of Heat Pumps
In the U.S., we typically use air-source heat pumps, and most often a subset known as air-to-air heat pumps. That means they absorb and release heat from the air (rather than water or earth), and deliver heating or cooling to your home through a forced-air system (rather than radiators). Among air-to-air heat pumps, two types are most common in residential homes.
Ducted Air-Source Heat Pump
This type of heat pump looks and acts a lot like a central AC. There’s an outdoor unit and an indoor unit, both of which have aluminum fins and coils to release or collect heat, connected by a refrigerant line filled with fluid that transports heat between the two units. The outdoor unit also has a compressor, which compresses and circulates the refrigerant.
The indoor unit hooks up to ducts inside your home, and a blower circulates the warm or cool air through those ducts and out of air vents placed around your house. According to CR’s member surveys, the overall median price paid for the purchase and installation of a ducted heat pump between 2016 and 2021 was $7,791, though that varies by brand.
Ductless (aka Mini-Split) Air-Source Heat Pump
This kind of system heats and cools air just like a ducted model, but it does not rely on ductwork to move warm or cool air through your house. Instead, the outdoor unit connects to one or more individual indoor air handlers, or “heads,” which are installed throughout your home. It’s a common, straightforward way to add a heat pump to a home or section of a home that doesn’t have ducts.
Typically the air-handler heads are placed high on a wall, but for homeowners who don’t like the look or don’t have the space, there are heads that can be placed inside the ceiling or floor. Mini-splits are also more energy-efficient than ducted heat pumps because they avoid the energy losses associated with ductwork.
CR doesn’t yet have enough brand-specific data to report on the prices members paid to purchase and install ductless mini-splits; according to HomeAdvisor, their installed cost can range from $2,000 to $14,500, depending on the capacity and the number of zones.
Other Types of Heat Pumps
There are a few other types of heat pumps that are proved to work well in some situations but are less common than air-source heat pumps.
Ground-source or geothermal heat pumps absorb and release heat underground, where the temperature is a constant 50° F to 60° F all year. They are highly efficient because they don’t have to compensate for big temperature swings the way air-source heat pumps do. However because the heat-exchanging pipes are buried underground (either horizontally or vertically), ground-source systems can be impractical for small lots or those with certain types of soils or landscapes.
Ground-source systems can cost from $6,000 to $30,000 or more. Federal and local incentives can reduce the cost significantly, and the systems are so energy-efficient that the savings from your utility bills could offset the cost of installation within 10 years, even by conservative estimates.
Water-source heat pumps work like ground-source systems, except they’re laid at the bottom of a pond, rather than underground. If you have an appropriate body of water on your property, these can be easier and less expensive to install than ground-source systems.
Air-to-water heat pumps use outdoor units similar to air-to-air models, but they distribute heat through a hot-water radiator system. Air-to-water heat pumps are common in much of Europe, but they’re not currently in the U.S. (even though many homes in the Northeast and Midwest rely on hydronic radiators for heat).
Why Buy a Heat Pump?
You already have one and need to replace it. If you live somewhere with cold winters, you might have heard about heat pumps only recently. In 2018, the U.S. Energy Information Administration reported that almost 14 percent of U.S. homes use a heat pump as their primary heating (and cooling) system.
So if your home already relies on a heat pump, and you’re happy with it, the simplest thing to do when it wears out (generally after 10 to 15 years of service) is to replace it with a similar model, which will probably be more efficient. CR members can see which brands of ducted heat pumps make their owners the happiest, based on data we’ve collected from our member survey.
You need to replace your central AC (or add new built-in air conditioning). In cooling mode, a heat pump works exactly like an air conditioner. The installation process for both systems is essentially the same, too. The cost of installing a heat pump tends to be higher than it is for installing a central AC with a similar efficiency rating and capacity, though the exact amount can vary. A search of various models showed installation cost differences ranging from 2 percent to more than 35 percent. Some state governments and utility companies offer tax incentives or cash rebates if you install a heat pump, mitigating some of the cost.
So if you’re replacing (or adding) an AC anyway, whether it’s a central system or a room unit, it may make sense to pay a little extra for a heat pump and keep your existing heating system as a backup for the coldest days and reap the rewards of high-efficiency heating on the milder days of the year (more on this kind of hybrid system later).
You want to add heat to a chilly room. A ductless, mini-split heat pump is an affordable and effective way to add climate control to parts of your house where the main system doesn’t quite work—like a finished attic, garage workshop, or home addition.
You heat with “delivered” fuels like propane or heating oil, or with an electric-resistance furnace or electric baseboard heaters. These are all expensive ways to heat a home, but depending on factors such as where you live and the cost of electricity, you’re likely to save money over time if you switch to a heat pump, even when you include the cost of installing it.
You want to significantly reduce your carbon footprint. Almost half of a typical home’s energy use goes toward heating. So anything you do to heat more efficiently, and with cleaner sources of energy, will go a long way toward making your home more sustainable. Switching from a gas furnace to a heat pump will reduce a home’s heating-related carbon emissions by an average of 40 percent, according to a 2022 study from the University of California, Davis. It’s one of the most impactful ways to reduce your carbon footprint, and it doesn’t require a lifestyle change.
Your home has ductwork. More than half of all homes in the U.S. already use ducts to distribute heating and cooling. A ducted heat pump can be connected to the existing ductwork to provide whole-home heating and cooling. The only caveat: Leaky, uninsulated ducts are bad for any heating system, but especially for heat pumps (more on that below).
You live somewhere with heat pump subsidies. Heat pumps—particularly models that work well in very cold climates—tend to cost more upfront than other types of heating appliances. For example, CR members surveyed paid a median price of $7,791 to purchase and install a heat pump, vs. $6,870 for gas furnaces. And sources we spoke to said whole-house heat pumps for cold climates can easily cost more than $10,000. (Though don’t forget, heat pumps also provide cooling.)
But with state or utility-based subsidies—whether they’re tax incentives or cash rebates—a heat pump can cost less than other heat-only systems. Air-source heat pump systems are not currently eligible for federal tax rebates, though ground-source heat pumps are.
When Is a Heat Pump Not So Practical?
Heat pumps aren’t the most practical heating solution for every home. Here are some scenarios in which it can be expensive, difficult, or impossible to install one.
Your house has no ducts. It can be difficult and expensive to add ducts to a home that doesn’t have them, and heat pumps built to work with hydronic heating systems are uncommon and expensive in the U.S. In this case, a ductless mini-split system is usually the easiest way to add a heat pump.
Your house is poorly insulated, or leaky. If yours is an older home, it’s always a good idea to upgrade your insulation and seal any air leaks, regardless of how you heat it. It’s also wise to wrap and seal your ductwork (if you have it). But good insulation is especially beneficial in homes that use heat pumps. Heat pumps heat more gently than other systems—it’s a constant trickle of warm air, rather than blasts of heat every few hours. If you have poor insulation, you’ll notice drafts and cold spots more often than you would with the higher temps of a traditional system.
Your electrical service is underpowered. Some homes, particularly older ones, have only 100-amp or even 60-amp electrical service. Technically you can run a heat pump on a system like this, especially if it’s a smaller-capacity mini-split. But if it’s a bigger heat pump, and you turn on too many additional appliances—or plug in an electric vehicle—you could trip the breaker and have to reset your system.
If you have your heat pump professionally installed, a good contractor should check your panel for capacity and may advise hiring an electrician to upgrade to the modern standard of 200 amps. You should expect to pay at least a couple of thousand dollars for that work.
You live in an extremely cold climate. The Department of Energy divides the U.S. into eight climate zones. The higher the number, the colder the winters. Basic heat pumps have been common in the lower-numbered zones for decades. But modern heat pumps in a properly designed system can provide all the heat a home will need up through zone 6.
In zones 7 and 8—which include the northern parts of North Dakota, Minnesota, Wisconsin, Michigan, Maine, and all of Alaska, where temperatures can drop below -25° F for days at a time—even today’s cold-climate heat pumps might not provide adequate heat. You’re likely to need a backup heating system if you live in one of these areas.
How to Choose a Heat Pump
Size (Capacity)
A heat pump that’s too small for your needs will struggle to keep your home comfortable. On the other hand, an oversized unit will cost more, and if it isn’t a variable-speed model, it will cycle on and off more often than it should. This decreases efficiency, stresses components, and leaves your home less comfortable.
A heat pump’s cooling capacity is measured in British thermal units per hour (Btu/hr.). Btu/hr. can also be expressed in “tons,” with 1 ton equaling 12,000 Btu/hr. To ensure that your heat pump is sized correctly, make sure your contractor does a load calculation based on a recognized method, such as the Air Conditioning Contractors of America (ACCA) Manual J. The calculations should be made after any air-sealing or insulation upgrades are made to your home and should be done whether you’re replacing a unit or installing a new system.
One nuance to consider: If you’re planning on keeping a backup heating system alongside your heat pump, you could consider getting an undersized heat pump. A contractor can help you figure out whether this makes sense in your home.
Note that heat pumps need far less capacity to heat a space than a furnace or boiler would because they’re much more energy-efficient. For example, if your home needed a 100,000-Btu/hr. furnace, it may need only a 36,000 BTU/hr. heat pump.
Compressor Type
The compressor is the heart of a heat pump—it’s the part that actually pumps the heat. Basic heat pumps have a single-speed compressor. It’s either on or off. This system works well enough, but the temperature and relative humidity in your home will swing up and down with the cycles. Some compressors have two speeds, which mitigates the swings, but they’re still present.
The gold standard is a variable-speed compressor. It’s designed to run almost constantly, adjusting itself over time to deliver only as much heating or cooling as it takes to keep your home comfortable. It’s also much better at keeping relative humidity under control than single-speed models are.
Variable-speed compressors not only keep your home more comfortable but also are more energy-efficient. It may seem counterintuitive, but it takes much less energy to move a tiny bit of heat all the time than to move a lot of heat quickly.
Efficiency
Some heat pumps use less energy than others to deliver the same level of comfort. In cooling mode, efficiency is commonly expressed as the seasonal energy-efficiency rating or SEER. The higher the SEER, the greater the efficiency. In heating mode, the measurement used is heating seasonal performance factor, or HSPF. Again, the higher the number, the more energy-efficient the unit.
Heat pumps with higher SEER and HSPF ratings tend to cost more, but they’ll often pay for themselves over time through lower energy costs, and they may be eligible for better tax incentives or rebates than less efficient models. Heat pumps with higher SEER ratings also tend to have higher HSPF ratings, though there’s no direct relationship between the two. If you live in a warm climate, pay closer attention to the SEER. In cold climates, look for a higher HSPF.
The minimum SEER allowed for a new split system heat pump in the U.S. today is 13, and 14 in the southern half of the country. The minimum HSPF is 8.2. Systems that meet Energy Star guidelines for efficiency have a minimum SEER of 15. The minimum federal standards are all set to increase in early 2023 to a SEER of no less than 14 in northern regions, and 15 in southern regions, as well as a minimum HSPF of 8.8. The most efficient models have a SEER of 33.1 or an HSPF of 14.
Climate Performance
If you live in a region with cold winters, you’ll need to either pick a heat pump that’s rated to work well in the lowest temperatures that your region regularly experiences or have a secondary heating system to back up your heat pump.
All air-source heat pumps struggle to perform as temperatures drop; the space they can effectively heat shrinks, and they don’t work as efficiently. The threshold for poor performance varies from model to model: Some heat pumps falter at 25° F, others at 17° F or lower.
Models marketed as cold-climate heat pumps can work to their full potential all the way down to 5° F and may deliver some heat even down to -20° F or lower. The best course is to work with a qualified local contractor who knows what kind of equipment works well in your area.
If you live in an area where the temperature rarely or never drops below freezing (32° F), a basic heat pump can handle the bulk of your heating and cooling needs. You can keep a simple electrical-resistance backup system (sometimes built into the heat pump itself) for unusual cold snaps.
Noise
Manufacturers publish the noise levels for their products in the user manual and often on their websites. They tend to include noise estimates across a variety of outdoor temperatures and fan speeds, measured in decibels. A lower rating is better, especially if the heat pump will be installed near a bedroom window.
Reliability
According to our member survey, reliability is by far the top predictor of an owner’s overall satisfaction with a heat pump. Consumer Reports members can see the predicted reliability and owner satisfaction ratings for 24 brands of heat pumps, based on data that CR members have shared about almost 13,500 heat pumps they’ve bought new and installed in their own homes between 2005 and 2021. Those findings are summarized in our guide to the Most and Least Reliable Heat Pumps.
Find the Right Contractor
As with most heating and cooling systems, it’s wise to hire a professional to handle the design and installation of a new heat pump system. The margin for error with heat pumps is smaller than with traditional heating systems, making proper sizing essential. Here are some tips for hiring a good installer.
Ask around. Seek referrals from neighbors, family members, business associates, or local green-energy resource groups. Heat pumps are still a niche product in colder parts of the country (though that is changing quickly), so green-energy resource groups might be able to help you find a contractor who is familiar with the technology and knows how to install a good system. It’s wise to get price quotes from at least three contractors.
Check their background. Contractors who bid on your installation should show you verification of bonding and insurance, plus any required contractor’s licenses. Check with your local Better Business Bureau and consumer affairs office for complaint records. It’s a plus if technicians are certified by a trade organization, such as North American Technician Excellence or HVAC Excellence, to service residential heating and cooling equipment. Those and similar programs assess the technician’s knowledge of specific types of equipment and their proper service methods.
Get specifics. Be leery of a contractor who bases estimates merely on house size or vague rules of thumb. Contractors who bid on your job should calculate the required heating and cooling capacity using a recognized method, such as one found in the ACCA’s Residential Load Calculation Manual, also called Manual J. An additional reference for assessing ductwork needs is Manual D. The calculations produce a detailed, room-by-room analysis of heating and cooling needs. Ask for a printout of all calculations and assumptions, including ductwork design.
Your contractor should also scope out a proper location for the outdoor unit. A compressor needs adequate airflow to operate correctly. Make sure to keep at least 2 to 3 feet of space between the unit and any plants or structures. There should also be 5 feet of clearance between the top of the unit and any trees above. You’ll also want to make sure there’s enough space for you or a technician to access and service the unit. Local building codes might have regulations about how close an outdoor compressor is allowed to be to a neighbor’s window or property line.
Do You Need a Backup Heating System?
With the right heat pump and system design for your home and regional climate, a backup heating system should not be necessary.
But in cold climates, keeping a backup system can be the most cost-effective way to keep your home comfortable. You could even think of it as a hybrid setup, rather than a system with a backup. You’ll use the heat pump most of the time (including the summer, when it provides all your cooling) and the backup system only on the coldest days when the heat pump can’t keep up. A contractor can set up the system to switch automatically at a specific outdoor temperature.
Hybrid systems still save a ton of energy and carbon emissions compared with most other setups and can offer some peace of mind in colder climates.
Here are a few common types of hybrid setups.
Electric strip: Common in mild climates, a simple electric heating element can be built into the heat pump itself or the indoor air handler. These strips use a ton of energy, but they’re very inexpensive to install and maintain, and it’s a cost-effective way to get through short cold snaps.
Mini-split plus radiators: Radiator systems that run on oil or propane, or “regular” electric-resistance heat, tend to be expensive to run, but mini-split systems that are big enough to heat your entire home tend to be expensive to install. A popular compromise: Install a smaller mini-split that can handle most of your heating (and cooling) needs, and keep the old radiator system for the coldest days.
Ducted heat pump plus furnace: It’s the same concept as the mini-split and radiator combo above. You’ll install the heat pump just like you’d install a central AC.
Heat Pump Maintenance
The conventional wisdom is that heat pumps should receive regular maintenance for optimal performance, although our reader survey showed no correlation between the frequency of maintenance and how likely a heat pump was to need maintenance or repairs. But a well-maintained system should run more efficiently.
If you hire a service technician, here’s what you’ll want them to do, once a year:
clean and flush the coils, drain the pan and drainage system, and vacuum the blower compartments. The contractor should also check to make sure that the system is properly charged with refrigerant, that there are no leaks, and that all mechanical components are working properly.
You can also handle some maintenance on your own. Clean grilles and filters monthly. Clear debris and dirt from condenser coils and check for blockages in the drainpipe. Follow the manufacturer’s directions for changing the filter, and the filter manufacturer’s recommendations for how often it should be changed. In general, the thicker a disposable filter, the less often it needs to be changed. (The HVAC filters we test last between three and 12 months.)