Head to head
Baxi 800 Combi 2 36kW vs Glow-worm Energy Combi 25C 25kW
The Baxi 800 Combi 2 36kW puts out 8kW more to the radiators and runs 4.6 litres a minute more hot water.
Last reviewed 13 September 2026
Key differences
- Central heating output: the Baxi 800 Combi 2 36kW puts out 8kW more to the radiators.
- Hot water flow rate: the Baxi 800 Combi 2 36kW runs 4.6 litres a minute more hot water.
- Warranty: the Baxi 800 Combi 2 36kW comes with 3 years more warranty.
- Hot water output: the Baxi 800 Combi 2 36kW has 10kW more hot water output.
- Seasonal efficiency: the Glow-worm Energy Combi 25C 25kW is 1 points more efficient.
Specifications side by side
| Baxi 800 Combi 2 36kW | Glow-worm Energy Combi 25C 25kW | |
|---|---|---|
| Hot water output | 36 kW | 25.7 kW |
| Central heating output | 26.4 kW | 18 kW |
| ErP class | A | A |
| Seasonal efficiency | 93% | 94% |
| Dimensions | 700 x 390 x 285 mm | 700 x 390 x 280 mm |
| Weight | 29.5 kg | 32 kg |
| Warranty | 10 years | 7 years |
| Hot water flow rate | 15 litres per minute | 10.4 litres per minute |
Sources: Baxi 800 Combi 2 36kW, Glow-worm Energy Combi 25C 25kW. Figures vary by model year and options, so check with the supplier before you commit.
Buy or hire the 800 Combi 2 36kW if...
- you want one that puts out 8kW more to the radiators
- you want one that runs 4.6 litres a minute more hot water
- you want one that comes with 3 years more warranty
- you want one that has 10kW more hot water output
A gas combi boiler with 36 kW of hot water output, sized for a larger house with two bathrooms. It delivers about 15 litres per minute of hot water, which decides how well a shower runs while a tap is on. Warranty: 10 years. Seasonal efficiency is 93%.
Full 800 Combi 2 36kW specifications →Buy or hire the Energy Combi 25C 25kW if...
- you want one that is 1 points more efficient
A gas combi boiler with 25.7 kW of hot water output, sized for a flat or small house with one bathroom. It delivers about 10.4 litres per minute of hot water, which decides how well a shower runs while a tap is on. Warranty: 7 years. Seasonal efficiency is 94%.
Full Energy Combi 25C 25kW specifications →Common questions
What is the difference between the Baxi 800 Combi 2 36kW and the Glow-worm Energy Combi 25C 25kW?
The Baxi 800 Combi 2 36kW puts out 8kW more to the radiators and runs 4.6 litres a minute more hot water. The Baxi 800 Combi 2 36kW is a gas combi boiler, 36 kW hot water output; the Glow-worm Energy Combi 25C 25kW is a gas combi boiler, 25.7 kW hot water output.
GetBrent is an independent directory and is not a dealer for, nor affiliated with, either manufacturer. Model and brand names are the trademarks of their owners.