Hot Tub Heat Pumps UK | Air Source Heat Pumps

Whisper-quiet operation

COP up to 16

Works from -10°C

App controlled

Why Switch to a Heat Pump?

If you're still heating your swim spa or swimming pool with an electric heater, you're paying far more than you need to. Air source heat pumps pull warmth from the ambient air and deliver it into your water — meaning for every 1KW of electricity you use, you can get up to 16KW of heat in return.

At Hortus Collection, we supply and install the UK's most advanced heat pump technology, so you spend less time worrying about energy bills and more time enjoying your swim spa or swimming pool.

Frequently Asked Questions

How does a swimming pool heat pump work?

A heat pump extracts warmth from the outside air and transfers it into your swimming pool water via a refrigerant cycle — the same principle as a fridge working in reverse. Because it moves heat rather than generates it, a heat pump produces up to 14 units of warmth for every 1 unit of electricity consumed, making it far cheaper to run than a traditional electric heater.

How long does it take to heat a hot tub?

From cold, a 1,500-litre hot tub typically takes 8–12 hours to reach temperature with a 7–9kW heat pump, or 5–8 hours with an 11kW model. In practice, most owners leave the heat pump running continuously on a lower setpoint, which uses less energy than heating from cold each time.

How much does it cost to run a swimming pool heat pump?

Running costs depend on your electricity tariff, ambient temperature, tub size and how well insulated your cover is. As a guide, heating a 1,000-litre hot tub to 38°C from cold tap water costs between 41p in summer to £2 in winter, saving £5.36 - £6.68 with a standard 3kW heater

Will a heat pump work in winter and cold weather?

Yes. All heat pumps in our range use full inverter compressors and operate effectively down to -15°C. Performance is reduced in very cold weather (COP drops), but the units continue to heat your water reliably throughout UK winters. Inverter models automatically modulate their output to match conditions, which is far more efficient than on/off models.

What COP should I look for?

COP (Coefficient of Performance) is the efficiency rating — a COP of 5 means you get 5kW of heat for every 1kW of electricity used. Look for a COP of at least 4 at 15°C. Our Mr Silence and AquaIntel models achieve COP ratings of up to 16 in warm conditions, and remain efficient well below 0°C thanks to full inverter technology.

What's the difference between Mr Silence and AquaIntel?

Both brands use inverter technology for quiet, efficient operation. The stylish Mr Silence focuses on near-silent performance (from 39dB) and is ideal for hot tubs, swim spas and smaller pools — the MS90 won a WhatSpa Best Buy Award 2026. AquaIntel offers excellent value at entry and mid-range outputs (5kW and 7kW) and suits most standard hot tubs. If in doubt, the Mr Silence MS90 is our most popular all-rounder.

What size heat pump do I need?

As a rough guide: a standard 1,000–1,500 litre hot tub suits a 7–9kW model; a large hot tub or small swim spa suits 9–11kW; a swim spa or pool up to 30,000 litres suits 11–21kW. The warmer your climate and the better insulated your cover, the smaller the unit you need. If you're unsure, contact us and we'll size it for you.