Head to head
Glow-worm Energy Combi 25C 25kW vs Worcester Bosch Greenstar 5800i AW 5kW
The Glow-worm Energy Combi 25C 25kW is a gas combi boiler, 25.7 kw hot water output. The Worcester Bosch Greenstar 5800i AW 5kW is a r290 monobloc air source heat pump, 6.80 kw heat output.
Last reviewed 13 September 2026
Specifications side by side
| Glow-worm Energy Combi 25C 25kW | Worcester Bosch Greenstar 5800i AW 5kW | |
|---|---|---|
| Dimensions | 700 x 390 x 280 mm | 800 x 1100 x 540 mm (H x W x D) |
| Weight | 32 kg | 143 kg |
| Hot water output | 25.7 kW | - |
| Central heating output | 18 kW | - |
| ErP class | A | - |
| Seasonal efficiency | 94% | - |
| Warranty | 7 years | - |
| Hot water flow rate | 10.4 litres per minute | - |
| Heat output | - | 6.80 kW at 7/35C |
| SCOP | - | 4.53 (MCS, 35C flow) |
| Refrigerant | - | R290 (propane) |
| Sound pressure | - | 42 dB(A) |
| Max flow temperature | - | 75C |
Sources: Glow-worm Energy Combi 25C 25kW, Worcester Bosch Greenstar 5800i AW 5kW. Figures vary by model year and options, so check with the supplier before you commit.
Buy or hire the Energy Combi 25C 25kW if...
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 →Buy or hire the Greenstar 5800i AW 5kW if...
Worcester Bosch's entry-size 5800i AW, using the natural refrigerant R290 and reaching a 75C flow temperature for existing radiator systems. It is marketed as one of the quieter units in this size at 42 dB(A) sound pressure.
Full Greenstar 5800i AW 5kW specifications →Common questions
What is the difference between the Glow-worm Energy Combi 25C 25kW and the Worcester Bosch Greenstar 5800i AW 5kW?
The Glow-worm Energy Combi 25C 25kW is a gas combi boiler, 25.7 kW hot water output; the Worcester Bosch Greenstar 5800i AW 5kW is a r290 monobloc air source heat pump, 6.80 kW heat 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.