If your heat pump isn’t keeping your home as warm as expected, it doesn’t necessarily mean the heat pump itself is faulty. The cause could sit with the equipment, system design, installation, commissioning, controls or even a change in how the home is being used.
The important question is:
Who takes responsibility for finding out why?
Because most homeowners shouldn’t be expected to diagnose a heating system themselves or work out whether they need to call the heat-pump manufacturer, installer, designer or somebody else.
A well-designed heating system should come with something just as important as good equipment:
clear responsibility for what happens when something isn’t right.
Why might a heat pump not be heating your home properly?
There isn’t one answer.
A heat pump is part of a complete heating system. For your home to reach and maintain the temperatures it was designed for, several things need to work together.
The heat pump needs to provide sufficient heat.
The radiators or underfloor heating need to deliver that heat into each room.
The pipework needs to distribute it correctly.
The controls need to be configured appropriately.
And the system needs to have been designed, installed and commissioned around the requirements of the home.
So when a home isn’t as warm as expected, the underlying cause could sit in several places.
What you’re experiencing | It could relate to… |
Home isn’t reaching the expected temperature | System design, sizing, emitters, controls, commissioning or equipment |
One or two rooms aren’t warm enough | Room heat loss, emitter sizing, balancing or controls |
Running costs are higher than expected | Operating temperature, controls, usage, weather, tariff or system performance |
Hot water isn’t meeting demand | Hot-water design, settings, usage or equipment |
Heat pump shows a fault or error | Equipment, electrical or installation issue |
These aren’t diagnoses.
They’re examples of why “my heat pump isn’t working properly” can mean several very different things.
And that distinction matters when we start talking about responsibility.
Does poor performance mean the heat pump is faulty?
Not necessarily.
Imagine the heat pump itself is operating exactly as its manufacturer intended.
But the home still isn’t getting warm enough.
The problem could be that the heating requirement of the home was underestimated.
Or the radiators may not be capable of providing enough heat at the system’s operating temperature.
The controls could have been configured incorrectly.
The system might not have been commissioned as intended.
There could also be a genuine equipment fault.
From the homeowner’s perspective, the experience can look similar:
“My new heating isn’t doing what I expected.”
But the solution — and the party responsible for it — may be completely different.
That’s why simply asking whether the heat pump is “working” isn’t always enough.
The heat pump can be working while the heating system around it isn’t delivering the intended outcome.
Who is responsible if a heat pump doesn’t perform as expected?
It depends on what has caused the problem and, on the responsibilities, agreed with the companies involved.
Broadly, there are four different areas to think about.
The equipment
If a component develops a covered fault, the manufacturer’s product warranty may apply.
Exactly what is covered, for how long and under what conditions will depend on the manufacturer and warranty terms.
But an equipment warranty principally concerns the equipment.
It doesn’t, by itself, tell you whether the heating system was designed correctly for your home.
The system design
Before installation, someone has to establish what the home needs and design a system capable of providing it.
That can include room-by-room heat loss, heat-pump selection, design temperatures, radiator or underfloor-heating output, hot-water requirements and controls.
These aren’t simply choices about which products to buy.
They’re engineering decisions.
If those decisions aren’t appropriate for the home, perfectly functional equipment cannot necessarily compensate for them.
This is why we argued in our guide to what a heat pump quote should actually include that homeowners should be able to see the thinking behind the proposal before they accept it.
The installation and commissioning
A good design still has to be installed correctly.
And once the physical work is complete, the heating system needs to be commissioned and configured.
That can include checking operation, setting controls and temperatures, balancing the heating system and making sure the completed installation is behaving as intended.
So responsibility doesn’t end when the equipment is fitted.
The way the system is operated
There are also factors that sit outside the original design and installation.
The temperatures you choose to maintain, heating schedules, hot-water use and changes to the home can all affect energy consumption and comfort.
Weather matters too.
That becomes particularly important when discussing running-cost estimates.
The purpose of identifying these different factors isn’t to give everyone a reason to pass responsibility elsewhere.
Quite the opposite.
It shows why homeowners need clarity about who will investigate the complete system when something doesn’t seem right.
What if your heat pump isn’t heating the house enough?
Start with the company responsible for your heating system rather than assuming you need to diagnose the cause yourself.
Explain what you’re experiencing as specifically as you can.
For example:
“The house isn’t reaching the temperature we expected.”
is more useful than:
“The heat pump doesn’t work.”
Similarly:
“The bedrooms reach temperature but the living room doesn’t.”
provides different information from:
“Every room is colder than expected.”
The provider can then investigate the system rather than starting with the assumption that a particular component is faulty.
Depending on the situation, that investigation might look at the original design, system settings, flow temperatures, emitter performance, controls, commissioning data or the heat pump itself.
The homeowner’s job should be to describe the problem.
It shouldn’t be to determine which company is responsible before anyone will help.
What if the home is warm, but the running costs are higher than expected?
This is a different type of performance question.
An estimated annual running cost isn’t the same as a guaranteed future energy bill.
Energy consumption can be affected by outside temperature, the temperatures maintained inside, hot-water use, operating temperatures, control settings and household behaviour.
The price you actually pay also depends on your electricity tariff.
That’s why a good proposal should explain the assumptions behind any running-cost estimate before installation.
Adlår’s own energy information, for example, distinguishes between modelled estimates and actual outcomes and explains that weather, household behaviour, building characteristics, system design, installation, commissioning and controls can all affect real-world performance.
So if actual energy use appears different from the estimate, the useful question isn’t immediately:
“Who got the number wrong?”
It’s:
“Why is actual performance different from what was modelled?”
That creates something that can be investigated.
Perhaps the home is being kept warmer than assumed.
Perhaps the weather has been unusually cold.
Perhaps the electricity tariff has changed.
Or perhaps the system is operating differently from the design assumptions.
A responsible provider should help distinguish between those possibilities rather than treating every difference as either a system fault or homeowner behaviour.
A warranty isn’t the same as responsibility for the heating system
This distinction is particularly important when comparing heat pump installers.
A heat pump might come with a manufacturer’s warranty.
Other components may have their own warranties.
There may also be protection relating to installation workmanship.
Those protections matter.
But they answer a different question from:
“Who takes responsibility if my home isn’t heating as expected?”
Consider a simple example.
The heat pump is tested and found to be operating correctly.
There is no covered manufacturing fault.
But one room consistently struggles to reach its intended temperature.
A product warranty doesn’t necessarily answer why.
You may instead need to understand whether the room’s heat loss was calculated correctly, whether the radiator can provide sufficient output, whether the system is balanced correctly or whether something else has changed.
That’s the difference between product protection and system accountability.
We’ll look more closely at exactly what heat-pump warranties protect — and what they don’t — later in this series.
Why system design matters when something goes wrong
This is where the work carried out before installation becomes particularly valuable.
If the heating system was designed from a detailed assessment, there is a reference point to return to.
What was the calculated heat loss of the home?
What was the requirement for the affected room?
What flow temperature was the system designed around?
What output was the radiator expected to provide?
What performance was the heat pump expected to achieve at the design conditions?
What assumptions were made?
Adlår’s Home Energy Assessment records this kind of design information before installation, including room-by-room heat loss, emitter output, design temperatures, system selection and expected performance.
That information isn’t useful only when choosing a heat pump.
It also gives you something against which the finished system can be understood.
Without a clear design, diagnosing poor performance can become much harder because there is less evidence of what the system was originally intended to do.
This is one reason we see good system design as part of long-term homeowner confidence, rather than simply an installation requirement.
So what should happen when something isn’t right?
The first response shouldn’t be an argument about whose fault it is.
It should be an investigation.
That means establishing what the homeowner is experiencing, comparing it with what the system was designed to achieve, and identifying the cause.
Sometimes that cause may be straightforward.
Sometimes several parts of the system may need checking.
And sometimes the heating system may be operating correctly but circumstances differ from those assumed when performance was estimated.
The important thing is having a clear route forward.
For homeowners, there are three useful questions to ask before choosing a heating-system provider:
Who do I contact if the system doesn’t perform as expected?
Who investigates whether the issue is with the equipment, design, installation or controls?
If something within your responsibility needs correcting, what happens next?
Those questions tell you something a warranty length alone cannot.
The Adlår approach: responsibility for the system, not just the equipment
At Adlår, we start with a simple belief:
If we design and install the heating system, homeowners shouldn’t be left to work out which part of that system is responsible when something doesn’t feel right.
That’s one reason our process begins with understanding the home before specifying the equipment.
Our Home Energy Assessment records the heating requirement, room-level heat loss, emitter performance, design temperatures and proposed system before installation.
That creates a design against which the completed system can be assessed.
It also sits behind the wider principle of Adlår’s Warmth Guarantee: moving the conversation beyond simply whether a piece of equipment is functioning and towards whether the heating system we designed is delivering the comfort it was designed to provide.
The precise protection, conditions and remedies are defined by the customer-facing guarantee and contractual terms, so those documents should always be the reference point for what is formally covered.
But the principle is straightforward:
Good engineering should come with clear accountability.
Five questions to ask about responsibility before choosing a heat pump installer
Before agreeing to an installation, make sure you can answer these:
- Who designed the complete heating system?
Not simply who supplied the heat pump, but who is responsible for the decisions about heat loss, sizing, flow temperature, emitters and hot water.
- What has the system been designed to achieve?
You should understand the intended comfort and performance outcomes, along with the assumptions behind any estimates.
- Who commissions and checks the finished system?
Good equipment and good design still need to become a correctly operating heating system.
- Who do I contact if something isn’t right?
You shouldn’t discover the answer only after a problem occurs.
- What is guaranteed, and what is estimated?
Equipment warranties, workmanship protection, performance estimates and specific guarantees aren’t interchangeable.
Understanding the distinction before installation can prevent considerable confusion afterwards.
Frequently asked questions
Why is my heat pump not heating my house enough?
There are several possible causes. The issue could relate to system sizing, flow temperature, radiator or underfloor-heating output, controls, commissioning, equipment or changes in the conditions under which the system is operating.
If your home isn’t reaching the temperatures it was designed for, contact the company responsible for the heating system so the cause can be investigated.
Does a heat pump not heating properly mean it is faulty?
No. A heat pump can be operating correctly while another part of the heating system prevents the home from receiving enough heat.
The complete system — including its design, emitters, controls, installation and commissioning — may need to be considered before the cause can be established.
Is the installer responsible if my heat pump doesn’t perform properly?
Responsibility depends on the cause of the problem and the contractual arrangements covering the design, installation, equipment and ongoing support.
This is why homeowners should establish before installation who is responsible for the complete system and what happens if it doesn’t deliver the intended outcome.
Is poor heat pump performance covered by the warranty?
Not necessarily.
A manufacturer’s warranty typically relates to covered faults with the equipment and is subject to its own terms and conditions. Poor heating performance could instead relate to system design, installation, commissioning, controls or other factors.
Always check the specific warranty and contractual terms that apply to your installation.
What should I do if my heat pump isn’t keeping my home warm?
Contact the company responsible for your heating system and explain exactly what you’re experiencing — for example, which rooms aren’t reaching temperature and when the problem occurs.
Avoid changing numerous system settings before seeking support unless you’ve been advised to do so, as understanding how the system is currently operating may help with diagnosis.
Good heating needs clear responsibility
When a heating system isn’t doing what you expected, you shouldn’t need to become the engineer.
You need someone who can understand the system, investigate what is happening and explain what comes next.
That’s why choosing a heat pump is about more than equipment specifications and warranty lengths.
It’s about understanding who designed the heating system, what they designed it to achieve and who remains accountable once it’s operating in your home.
Because confidence doesn’t come from believing that nothing will ever need attention.
It comes from knowing what happens if it does.
