How Long Does a Heat Pump Installation Take?

One of the first questions homeowners ask when considering a heat pump is: how long will the installation actually take? The short answer is two to four days for an air source heat pump and one to two weeks for a ground source system. But several factors can push those timescales up or down.

This guide breaks down exactly how long each stage takes, what factors can extend the timeline, and how to plan around the disruption so it causes as little inconvenience as possible.

Air Source Heat Pump: 2 to 4 Days

A standard air source heat pump installation in a typical three-bedroom semi-detached house takes two to four working days. Here is how that time breaks down:

Day 1: Removal and preparation (6-8 hours)

Drain and disconnect the existing boiler
Remove the old boiler, header tanks (if applicable), and any redundant pipework
Prepare the outdoor base for the heat pump unit (concrete pad or pre-cast slab)
Begin routing new pipework from the outdoor unit location to the indoor system
Core-drill the external wall for pipe penetration

Day 2: Main installation (8-10 hours)

Position and secure the outdoor heat pump unit on its base
Install the hot water cylinder (if needed)
Complete the pipework connections between outdoor and indoor units
Insulate all pipework thoroughly
Replace or upgrade any radiators that need upsizing
Install new controls, thermostat, and weather compensation sensor

Day 3: Electrical work and commissioning (6-8 hours)

Complete the electrical connection (dedicated circuit from consumer unit)
Fill, pressurise, and leak-test the system
Power on and run initial diagnostics
Commission the system to MCS standards
Programme controls and set up weather compensation
Handover to homeowner with full documentation

Day 4 (if needed): Finishing touches

More complex installations may spill into a fourth day. This is common when radiator upgrades are extensive, pipework routing is complicated, or the electrical supply needs upgrading. Some installers prefer to commission on a separate day to allow the system to settle.

Ground Source Heat Pump: 1 to 2 Weeks

Ground source installations take significantly longer because of the ground works required. The indoor installation is similar to an air source system, but the ground loop adds substantial time.

Horizontal ground loop: 3 to 5 additional days

A digger excavates trenches across your garden, typically 1 to 1.5 metres deep and covering 200 to 400 square metres of ground. The loop pipework is laid in the trenches and backfilled. This requires good weather and dry ground — wet conditions can cause delays.

Vertical borehole: 2 to 4 additional days

A specialist drilling rig bores one or more holes 75 to 200 metres deep. This is quicker than horizontal trenching and requires less garden space, but the drilling equipment is large and noisy. Access to your garden for the rig needs to be considered early in the planning stage.

Total timeline for ground source

Ground works: 3 to 5 days (horizontal) or 2 to 4 days (borehole)
Indoor installation: 2 to 4 days
Commissioning: 1 day
Total: 6 to 10 working days, or roughly 1 to 2 calendar weeks

Factors That Extend Installation Time

Several things can push your installation beyond the standard timeframe:

Property size and complexity

A one-bedroom flat may take just a day and a half. A four-bedroom detached house with multiple heating zones could take five days. Larger homes mean more pipework, more radiators to check or upgrade, and a bigger system to commission.

Radiator upgrades

If several radiators need replacing with larger units (because heat pumps run at lower flow temperatures than boilers), this adds time. Swapping four or five radiators might add half a day. Replacing ten or more could add a full day. Read more about whether you need new radiators.

Pipework complications

If the route from the outdoor unit to the indoor system is long or awkward — running through a garage, under floorboards, or through multiple walls — pipework takes longer. Houses where the boiler is on the opposite side from where the heat pump needs to sit are particularly affected.

Electrical supply upgrades

If your consumer unit needs upgrading, or if a new electrical supply is required (rare but possible for larger systems), the electrical work could add an extra day. This is usually identified during the survey so you will know in advance.

Cylinder installation from scratch

If you currently have a combi boiler and no hot water cylinder, installing one adds time. The cylinder needs a suitable location, pipework connections, and possibly a new immersion heater backup. This typically adds three to five hours to the installation.

Access difficulties

Narrow side passages, steep gardens, or restricted parking for the installation van can all slow things down. If equipment has to be carried a long distance from the van to the installation point, every task takes a bit longer.

Weather

Outdoor work — positioning the heat pump, drilling through walls, laying ground loops — is weather-dependent. Heavy rain or very cold conditions can slow progress or force delays. This is more of a factor for ground source installations.

The Full Timeline: Survey to Switch-On

The physical installation is just part of the overall timeline. Here is the complete picture from first contact to having a working heat pump:

Getting quotes and surveys: 2 to 4 weeks
Choosing an installer: 1 to 2 weeks
BUS grant application and approval: 2 to 4 weeks
Waiting for installation date: 2 to 12 weeks (depends on installer availability)
Physical installation: 2 to 4 days (ASHP) or 1 to 2 weeks (GSHP)

Total from first enquiry to working system: typically 8 to 20 weeks. If you want your heat pump installed before winter, start the process in spring.

How to Minimise Installation Time

You cannot rush a proper installation, but you can avoid unnecessary delays:

Clear the work areas in advance: Move furniture away from radiators, clear the outdoor installation area, and ensure good access throughout the house
Have your EPC ready: If you need an Energy Performance Certificate for the BUS grant, get it done early
Respond quickly to your installer: When they need decisions or information, prompt replies keep things moving
Book well ahead: Good installers are busy. Booking 8 to 12 weeks ahead gives you more choice of dates
Consider timing: Spring and early summer installations tend to have shorter lead times than autumn, when everyone is rushing to get heat pumps in before winter

For a complete preparation guide, see our installation checklist.

Can You Stay in Your Home During Installation?

Yes — most homeowners stay in their home throughout the installation. The main inconvenience is temporary loss of heating and hot water, typically from day one (when the old boiler is removed) until day three or four (when the new system is commissioned). An electric shower will still work, and electric heaters can keep things comfortable.

Read our full guide on what disruption to expect for practical tips on managing the installation period.

Frequently Asked Questions

Can a heat pump be installed in one day?

In theory, a very small air source system in a well-prepared home could be installed in a single long day. In practice, two days is the realistic minimum for a proper installation with full commissioning. Be wary of anyone promising a one-day installation for a standard home.

Why do some installers quote longer than others?

Differences in team size, approach, and thoroughness. A two-person team may take four days where a three-person team takes three. Longer quotes are not necessarily worse — they may indicate more attention to detail during commissioning.

Does the time of year affect installation time?

The physical work takes roughly the same time year-round, but winter installations carry more risk of weather delays for outdoor work. Scheduling is also tighter in autumn when demand peaks.

How long will I be without heating and hot water?

Typically two to three days from when the old boiler is disconnected to when the new system is commissioned. Some installers can minimise this by doing preparatory work before disconnecting the old system.

What if the installation takes longer than expected?

Good installers will warn you if complications arise. Extra time is usually charged at the agreed daily rate, but this should be discussed upfront. Ask about this when comparing quotes.

Is a ground source installation worth the extra time?

Ground source heat pumps are more efficient than air source, especially in very cold weather, and they are silent in operation. Whether the extra installation time and cost is worthwhile depends on your priorities and budget. See our installation guide for a full comparison.

Planning your installation timeline? Get free quotes from MCS-certified installers who can survey your home and give you an accurate installation timeframe. Use our calculator to estimate costs, or start with the suitability checker to confirm your home is a good fit.