PRO3 vs COMBI vs COMBI+
Choosing the Right Quooker Reservoir
The reservoir is the heart of your Quooker system — the component that makes instant boiling water possible 24 hours a day. Quooker offers three reservoir sizes: PRO3 (3 litres), COMBI (7 litres), and COMBI+ (10 litres). Choosing the right one is the single most important decision when building your system.
PRO3 — Compact Efficiency (3 Litres)
The PRO3 is Quooker's most compact reservoir. Designed for small households and limited cabinet space, it delivers up to 1 litre of boiling water at a time — enough for several cups of tea, instant coffee, or blanching vegetables.
Key specifications:
- Capacity: 3 litres
- Boiling water delivery: up to 1 litre at a time
- Dimensions: 280mm × 280mm × 320mm
- Power consumption: approx. €0.30/day in standby
- Recovery time: approximately 10 minutes to re-boil 1 litre
- Cold/hot water: separate cold water handle (requires second tap hole or side valve)
Best for: Singles, couples, small flats, offices, or as a secondary system in a utility room. Anyone with limited under-sink space.
Not ideal for: Large families, frequent pasta/rice cooking, or anyone who needs more than 1 litre of boiling water at once.
COMBI — The All-Rounder (7 Litres)
The COMBI is Quooker's most popular reservoir — and for good reason. With 7 litres capacity and up to 3 litres of boiling water at a time, it handles everything from morning tea for the family to cooking dinner for guests. The COMBI also includes a cold water connection, meaning you only need one tap hole for both boiling and cold water.
Key specifications:
- Capacity: 7 litres
- Boiling water delivery: up to 3 litres at a time
- Dimensions: 280mm × 280mm × 430mm
- Power consumption: approx. €0.40/day in standby
- Recovery time: approximately 20 minutes to re-boil 3 litres
- Cold/hot water: integrated cold water function — single tap hole required
Best for: Most households (2–4 people). The sweet spot between capacity, size, and price.
Not ideal for: Very large families (4+), frequent heavy cooking, or anyone planning to add CUBE sparkling water (consider COMBI+ for extra reserve).
COMBI+ — Maximum Capacity (10 Litres)
The COMBI+ is Quooker's largest domestic reservoir. With 10 litres capacity, it delivers up to 5 litres of boiling water at a time — enough to fill a large pasta pot, blanch vegetables for a dinner party, or make filter coffee for a crowd.
Key specifications:
- Capacity: 10 litres
- Boiling water delivery: up to 5 litres at a time
- Dimensions: 280mm × 280mm × 520mm
- Power consumption: approx. €0.50/day in standby
- Recovery time: approximately 25 minutes to re-boil 5 litres
- Cold/hot water: integrated cold water function — single tap hole required
Best for: Large families (4+ people), frequent entertainers, anyone who boils large volumes of water regularly. Also the best choice when combined with CUBE, as the larger reserve ensures you always have boiling water available even when the CUBE is dispensing chilled sparkling water.
Not ideal for: Small kitchens with very limited under-sink space (check cabinet dimensions first).
Quick Comparison
| Feature | PRO3 | COMBI | COMBI+ |
|---|---|---|---|
| Capacity | 3 litres | 7 litres | 10 litres |
| Boiling at a time | ~1 litre | ~3 litres | ~5 litres |
| Ideal household size | 1–2 people | 2–4 people | 4+ people |
| Cold water integrated | No | Yes | Yes |
| CUBE compatible | Yes | Yes | Yes (best) |
| Daily running cost | ~€0.30 | ~€0.40 | ~€0.50 |
| Cabinet height needed | 320mm | 430mm | 520mm |
Which Reservoir Should You Choose?
If you live alone or as a couple: The PRO3 is the smart choice. It costs less, takes less space, and provides all the boiling water two people need for daily use.
If you have a family of 2–4: The COMBI is the sweet spot. It delivers enough boiling water for breakfast, cooking, and drinks throughout the day, with the convenience of integrated cold water.
If you have a large family, entertain often, or want CUBE: Go for the COMBI+. The extra reserve ensures you never run out of boiling water, even when the CUBE system is active.
Important installation note: All reservoirs require a minimum of 280mm × 280mm of floor space and sufficient cabinet height. Measure your under-sink cabinet before deciding. See our installation guide for full dimensional requirements.
Reservoir and CUBE Compatibility
All three reservoirs are compatible with the Quooker CUBE sparkling water system. However, if you plan to add CUBE, we recommend the COMBI or COMBI+. The CUBE draws from the same reservoir, so a larger capacity ensures you don't run out of boiling water while the CUBE is producing sparkling water.
Read our Quooker CUBE Explained guide for detailed information on CUBE compatibility and setup.
Warranty and Support
All genuine Quooker reservoirs carry the manufacturer's warranty. As an Official Quooker Partner, we ensure you receive full support for your system. See our Warranty page for detailed warranty information per product type.