Heat Pump Installation Checklist: Before, During, After

Having a heat pump installed involves a lot of moving parts — surveys, grants, preparation, the installation itself, and getting to grips with a new system afterwards. It is easy to forget something important in the process.

This practical checklist covers everything you need to do before, during, and after your heat pump installation. Print it off, tick items as you go, and you will stay on top of the entire process from start to finish.

Before Installation: Weeks and Months Ahead

Research and planning

Check whether a heat pump is suitable for your home — use our suitability checker as a starting point
Understand the different types: air source vs ground source
Review realistic costs and running costs for your property type
Check grant eligibility — the £7,500 BUS grant covers most homeowners in England and Wales
Get your EPC (Energy Performance Certificate) if you do not have a current one — needed for the BUS grant
If your EPC recommends loft or cavity wall insulation, get these done first

Getting quotes

Get at least three quotes from MCS-certified installers
Verify each installer's MCS certification on the official database
Ensure each installer conducts a full room-by-room heat loss survey
Check that quotes are fully itemised (heat pump model, cylinder, radiators, pipework, electrical, controls, BUS grant deduction)
Ask about warranty terms — both manufacturer and installer workmanship
Ask for references from previous customers
Check online reviews (Google, Trustpilot)
Compare quotes carefully — see our guide on choosing an installer

Choosing your installer

Select your preferred installer based on price, quality, experience, and communication — not price alone
Confirm the installation date and expected duration
Confirm who handles the BUS grant application (it should be the installer)
Understand the payment schedule — when deposits and final payments are due
Get everything in writing: quote, specification, timeline, warranty, payment terms

Before Installation: The Week Before

Preparing your home

Clear furniture at least 30cm away from any radiators being replaced
Remove items from the airing cupboard or wherever the hot water cylinder will go
Clear the outdoor area where the heat pump unit will be installed — move garden furniture, pots, bins, and anything else within 2 metres of the planned location
Ensure clear pathways for the installers to move between rooms and carry equipment
If you have wooden floors, lay dust sheets along the main routes (or ask your installer if they provide their own)
Take photos of the areas before work begins — useful if there are any disputes about pre-existing damage

Practical preparations

Arrange parking for the installer's van as close to the house as possible
Inform neighbours that installation work will be happening — there will be some noise, especially from core drilling on day one
If you have pets, plan where they will stay during the installation (away from work areas)
Stock up on essentials: you will have no heating or hot water for 2 to 3 days during the changeover
Charge portable devices and have a kettle accessible (cold water taps will still work)
If installing in winter, get electric heaters and extra blankets ready
If you have an electric shower, check it works — it will be your only shower option during installation

Confirm with your installer

Confirm arrival time (typically 8:00–8:30)
Confirm how many people will be on site each day
Confirm the planned duration
Ask whether the BUS grant voucher has been approved
Confirm all equipment has been ordered and will arrive on time

During Installation: Day by Day

Day 1: Removal and preparation

Installers drain and remove the old boiler and any header tanks
Old boiler gas/oil supply is safely disconnected and capped
Outdoor base for the heat pump is prepared
Core drilling through the external wall is completed (the noisiest part — about 15 to 30 minutes)
Initial pipework routing begins

What to check: old boiler and tanks are removed and disposed of responsibly. Wall penetration is neat and will be sealed properly.

Day 2: Main installation

Outdoor heat pump unit is positioned and secured on its base
Hot water cylinder is installed
Pipework from outdoor unit to indoor system is completed and insulated
Any radiator upgrades are fitted
Controls and sensors are positioned

What to check: outdoor unit is level and secure. Pipework is fully insulated (no gaps or bare sections). Radiators are correctly positioned and brackets are solid.

Day 3: Electrical, testing, and commissioning

Electrical connection is completed (dedicated circuit from consumer unit)
System is filled with water and inhibitor, pressurised, and leak-tested
All radiators are bled to remove air
Heat pump is powered on and run through initial diagnostics
System is commissioned to MCS standards
Controls are programmed: heating schedule, hot water schedule, weather compensation
Handover takes place

Questions to ask during the handover

How do I adjust the heating temperature?
How do I change the heating and hot water schedules?
What is weather compensation and why should I not override it?
What are defrost cycles, and what will I notice?
What is the normal system pressure, and how do I top it up?
When should I book the first annual service?
Who do I contact if something goes wrong?

During Installation: Your Checklist of Things to Verify

You are not a heating engineer, but you can still check these common-sense items:

The outdoor unit is level, secure, and positioned away from bedroom windows (for noise)
All external pipework is fully insulated with no gaps
The wall penetration is sealed with fire-rated sealant
New radiators are level and securely bracketed
The hot water cylinder is accessible for future servicing
The electrical isolator switch is accessible near the outdoor unit
The weather compensation sensor is fitted on a north-facing wall
The area is cleaned up — no debris, old equipment removed, dust sheets taken down

After Installation: The First Week

Run the heating for several hours and check that every radiator heats up evenly
Check hot water reaches a comfortable temperature (around 48 to 50 degrees Celsius at the tap)
Note the system pressure on the gauge — this is your baseline. It should remain stable
Listen to the outdoor unit — it should be a steady hum, not rattling, clanking, or excessively loud
Do not adjust the weather compensation settings — let the system run as the installer set it up
Expect radiators to feel warm rather than hot — this is normal and by design
Note any defrost cycles (steam from the outdoor unit, fan speed changes) — these are normal in cold weather

After Installation: The First Month

Monitor your energy usage — are electricity bills in line with what was estimated? Use the calculator for comparison
If any rooms feel too cold or too warm, contact your installer to adjust settings — do not try to fix it by turning the thermostat up to maximum
Check the system pressure every week or two — if it drops significantly, there may be a slow leak that needs investigating
Keep the outdoor unit clear of leaves, debris, and cobwebs that could restrict airflow
If your installer offers a follow-up visit to fine-tune settings, take it — first-month adjustments can improve efficiency noticeably

After Installation: Documentation Checklist

Make sure you have received and filed all of the following:

MCS installation certificate
Manufacturer's warranty documents (check the warranty is registered)
Building regulations compliance certificate or Competent Persons Scheme notification
Commissioning record with measured values
Heat loss calculations and system design documents
User manual for the heat pump controls
Installer's contact details for aftercare and emergencies
Invoice showing the BUS grant deduction

After Installation: Ongoing Maintenance

Book an annual service with a qualified heat pump engineer
Keep the area around the outdoor unit clear (at least 30cm clearance on all sides)
Check system pressure every month or two
Replace the system filter annually or as recommended by your installer
Keep your installer's contact details accessible
Read our full installation guide if you want to understand any aspect in more detail

Frequently Asked Questions

What is the most important thing to check before installation?

That your installer is genuinely MCS-certified and has conducted a proper room-by-room heat loss survey. Everything else flows from these two things.

What should I do if something does not feel right during installation?

Ask the lead installer. They should be happy to explain what they are doing and why. If you have concerns they cannot address, contact the company's office.

How long until I know if the system is working properly?

You should notice even heating within the first day of operation. Full optimisation — weather compensation fine-tuning, schedule adjustments — may take a few weeks. If something feels wrong after a fortnight, contact your installer.

What if I lose some of the documentation?

Your installer should be able to provide copies. The MCS certificate is also recorded on the MCS database and can be retrieved. Manufacturer warranty information can usually be obtained from the manufacturer directly using the serial number.

Do I need to do anything special before an annual service?

Not really. Just make sure the engineer has access to the outdoor unit, the indoor controls, the hot water cylinder, and the consumer unit. Clear any clutter from around these areas.

Can I use this checklist for ground source heat pumps too?

Yes. Everything on this checklist applies to both air source and ground source installations. Ground source adds the additional step of ground works (trenching or borehole drilling), which your installer will plan and schedule as part of the overall installation.

Ready to start the process? Get free quotes from MCS-certified heat pump installers and begin working through this checklist. Check your eligibility for the BUS grant, or use the suitability checker to confirm a heat pump is right for your home.