Baxi 600 System 2 Gas System Boiler - 615 / 618 / 624 (7798687 / 7802020 / 7802241)
The Baxi 600 System 2 is a wall-hung condensing gas system boiler available in three outputs — 15 kW (615), 18 kW (618), and 24 kW (624) — making it an outstanding choice whenever you need plentiful, simultaneous hot water across multiple bathrooms. Built around a stainless steel heat exchanger, it achieves an ErP A-rating and 93% seasonal efficiency, cutting running costs while reducing your carbon footprint. A seven-year parts and labour warranty (when registered within 30 days) and compatibility with Baxi uSense smart controls complete a boiler that balances everyday practicality with long-term reliability.
The stainless steel heat exchanger offers superior resistance to corrosion and scale compared to aluminium alternatives, contributing to the boiler's long service life and consistent thermal performance across all three output sizes.
All three models achieve 93% seasonal efficiency and hold an ErP A-rating for central heating, meeting the EU Energy-related Products Directive standards and helping to keep annual gas bills meaningfully lower than older non-condensing boilers.
The pre-heated siphonic condensate trap warms condensate before it exits the boiler, discharging it all at once rather than in small trickles. This significantly reduces the risk of frozen condensate pipes in cold weather, avoiding winter shutdowns and costly callouts.
All models can be manually converted between natural gas (G20) and LPG (G31) without purchasing an additional accessory kit. The conversion is carried out by a Gas Safe engineer via the boiler's gas valve settings, making it cost-effective for off-grid properties.
The built-in EasyFill permanent filling link lets the homeowner top up system pressure without needing to attach a temporary hose or call an engineer, simplifying routine maintenance and helping maintain optimum boiler performance between services.
The 600 System 2 supports OpenTherm modulating control, allowing compatible thermostats such as Nest and Hive to vary boiler output rather than simply switching it on and off. The optional Baxi uSense Wi-Fi thermostat adds smartphone scheduling and remote control capability.
At just 700 mm high × 390 mm wide × 285 mm deep and weighing only 28 kg, the 600 System 2 is designed to fit neatly inside a standard 290 mm-deep kitchen or utility cupboard, keeping hallways and living spaces clutter-free.
The boiler is certified for use with natural gas containing up to 20% hydrogen (H₂), ensuring it is prepared for the UK government's planned transition to low-carbon hydrogen-blended gas networks without requiring hardware upgrades.
Register within 30 days of installation, complete the Benchmark Commissioning Checklist, and ensure the boiler receives an annual service to maintain the full 7-year parts and labour warranty — one of the longer manufacturer-backed guarantees in this product category.
| Specification | 615 System 2 | 618 System 2 | 624 System 2 |
|---|---|---|---|
| Baxi Part Number (MPN) | 7798687 | 7802020 | 7802241 |
| Gas Council Number | 41-884-01 | 41-884-02 | 41-484-03 |
| Heat Output (kW) | 15 kW | 18 kW | 24 kW |
| Boiler Type | Wall-hung condensing gas system boiler | ||
| Seasonal Efficiency | 93% | ||
| ErP Energy Rating | A (Central Heating) | ||
| Heat Exchanger Material | Stainless steel | ||
| Gas Type | Natural Gas (G20) / LPG (G31) — manual conversion, no kit required | ||
| Hydrogen Compatibility | Suitable for up to 20% H₂ blend | ||
| CH Flow Temperature Range | 25 – 80 °C (adjustable) | ||
| Max System Pressure | 3 bar | ||
| Electrical Supply | 230 V / 50 Hz / single phase | ||
| Dimensions (H × W × D) | 700 × 390 × 285 mm | ||
| Weight | 28 kg | ||
| Minimum Cupboard Depth | 290 mm | ||
| Condensate Trap | Pre-heated siphonic (anti-freeze) | ||
| Filling System | EasyFill permanent filling link | ||
| Controls Compatibility | OpenTherm; Baxi uSense (optional); Nest, Hive & other OT thermostats | ||
| Cylinder Compatibility | Baxi cylinders; Megaflo Eco range | ||
| Warranty | 7 years parts & labour (registration required within 30 days) | ||
Original: $2,151.37
-65%$2,151.37
$752.98More Images
Baxi 600 System 2 Gas System Boiler - 615 / 618 / 624 (7798687 / 7802020 / 7802241)
The Baxi 600 System 2 is a wall-hung condensing gas system boiler available in three outputs — 15 kW (615), 18 kW (618), and 24 kW (624) — making it an outstanding choice whenever you need plentiful, simultaneous hot water across multiple bathrooms. Built around a stainless steel heat exchanger, it achieves an ErP A-rating and 93% seasonal efficiency, cutting running costs while reducing your carbon footprint. A seven-year parts and labour warranty (when registered within 30 days) and compatibility with Baxi uSense smart controls complete a boiler that balances everyday practicality with long-term reliability.
The stainless steel heat exchanger offers superior resistance to corrosion and scale compared to aluminium alternatives, contributing to the boiler's long service life and consistent thermal performance across all three output sizes.
All three models achieve 93% seasonal efficiency and hold an ErP A-rating for central heating, meeting the EU Energy-related Products Directive standards and helping to keep annual gas bills meaningfully lower than older non-condensing boilers.
The pre-heated siphonic condensate trap warms condensate before it exits the boiler, discharging it all at once rather than in small trickles. This significantly reduces the risk of frozen condensate pipes in cold weather, avoiding winter shutdowns and costly callouts.
All models can be manually converted between natural gas (G20) and LPG (G31) without purchasing an additional accessory kit. The conversion is carried out by a Gas Safe engineer via the boiler's gas valve settings, making it cost-effective for off-grid properties.
The built-in EasyFill permanent filling link lets the homeowner top up system pressure without needing to attach a temporary hose or call an engineer, simplifying routine maintenance and helping maintain optimum boiler performance between services.
The 600 System 2 supports OpenTherm modulating control, allowing compatible thermostats such as Nest and Hive to vary boiler output rather than simply switching it on and off. The optional Baxi uSense Wi-Fi thermostat adds smartphone scheduling and remote control capability.
At just 700 mm high × 390 mm wide × 285 mm deep and weighing only 28 kg, the 600 System 2 is designed to fit neatly inside a standard 290 mm-deep kitchen or utility cupboard, keeping hallways and living spaces clutter-free.
The boiler is certified for use with natural gas containing up to 20% hydrogen (H₂), ensuring it is prepared for the UK government's planned transition to low-carbon hydrogen-blended gas networks without requiring hardware upgrades.
Register within 30 days of installation, complete the Benchmark Commissioning Checklist, and ensure the boiler receives an annual service to maintain the full 7-year parts and labour warranty — one of the longer manufacturer-backed guarantees in this product category.
| Specification | 615 System 2 | 618 System 2 | 624 System 2 |
|---|---|---|---|
| Baxi Part Number (MPN) | 7798687 | 7802020 | 7802241 |
| Gas Council Number | 41-884-01 | 41-884-02 | 41-484-03 |
| Heat Output (kW) | 15 kW | 18 kW | 24 kW |
| Boiler Type | Wall-hung condensing gas system boiler | ||
| Seasonal Efficiency | 93% | ||
| ErP Energy Rating | A (Central Heating) | ||
| Heat Exchanger Material | Stainless steel | ||
| Gas Type | Natural Gas (G20) / LPG (G31) — manual conversion, no kit required | ||
| Hydrogen Compatibility | Suitable for up to 20% H₂ blend | ||
| CH Flow Temperature Range | 25 – 80 °C (adjustable) | ||
| Max System Pressure | 3 bar | ||
| Electrical Supply | 230 V / 50 Hz / single phase | ||
| Dimensions (H × W × D) | 700 × 390 × 285 mm | ||
| Weight | 28 kg | ||
| Minimum Cupboard Depth | 290 mm | ||
| Condensate Trap | Pre-heated siphonic (anti-freeze) | ||
| Filling System | EasyFill permanent filling link | ||
| Controls Compatibility | OpenTherm; Baxi uSense (optional); Nest, Hive & other OT thermostats | ||
| Cylinder Compatibility | Baxi cylinders; Megaflo Eco range | ||
| Warranty | 7 years parts & labour (registration required within 30 days) | ||
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Description
The Baxi 600 System 2 is a wall-hung condensing gas system boiler available in three outputs — 15 kW (615), 18 kW (618), and 24 kW (624) — making it an outstanding choice whenever you need plentiful, simultaneous hot water across multiple bathrooms. Built around a stainless steel heat exchanger, it achieves an ErP A-rating and 93% seasonal efficiency, cutting running costs while reducing your carbon footprint. A seven-year parts and labour warranty (when registered within 30 days) and compatibility with Baxi uSense smart controls complete a boiler that balances everyday practicality with long-term reliability.
The stainless steel heat exchanger offers superior resistance to corrosion and scale compared to aluminium alternatives, contributing to the boiler's long service life and consistent thermal performance across all three output sizes.
All three models achieve 93% seasonal efficiency and hold an ErP A-rating for central heating, meeting the EU Energy-related Products Directive standards and helping to keep annual gas bills meaningfully lower than older non-condensing boilers.
The pre-heated siphonic condensate trap warms condensate before it exits the boiler, discharging it all at once rather than in small trickles. This significantly reduces the risk of frozen condensate pipes in cold weather, avoiding winter shutdowns and costly callouts.
All models can be manually converted between natural gas (G20) and LPG (G31) without purchasing an additional accessory kit. The conversion is carried out by a Gas Safe engineer via the boiler's gas valve settings, making it cost-effective for off-grid properties.
The built-in EasyFill permanent filling link lets the homeowner top up system pressure without needing to attach a temporary hose or call an engineer, simplifying routine maintenance and helping maintain optimum boiler performance between services.
The 600 System 2 supports OpenTherm modulating control, allowing compatible thermostats such as Nest and Hive to vary boiler output rather than simply switching it on and off. The optional Baxi uSense Wi-Fi thermostat adds smartphone scheduling and remote control capability.
At just 700 mm high × 390 mm wide × 285 mm deep and weighing only 28 kg, the 600 System 2 is designed to fit neatly inside a standard 290 mm-deep kitchen or utility cupboard, keeping hallways and living spaces clutter-free.
The boiler is certified for use with natural gas containing up to 20% hydrogen (H₂), ensuring it is prepared for the UK government's planned transition to low-carbon hydrogen-blended gas networks without requiring hardware upgrades.
Register within 30 days of installation, complete the Benchmark Commissioning Checklist, and ensure the boiler receives an annual service to maintain the full 7-year parts and labour warranty — one of the longer manufacturer-backed guarantees in this product category.
| Specification | 615 System 2 | 618 System 2 | 624 System 2 |
|---|---|---|---|
| Baxi Part Number (MPN) | 7798687 | 7802020 | 7802241 |
| Gas Council Number | 41-884-01 | 41-884-02 | 41-484-03 |
| Heat Output (kW) | 15 kW | 18 kW | 24 kW |
| Boiler Type | Wall-hung condensing gas system boiler | ||
| Seasonal Efficiency | 93% | ||
| ErP Energy Rating | A (Central Heating) | ||
| Heat Exchanger Material | Stainless steel | ||
| Gas Type | Natural Gas (G20) / LPG (G31) — manual conversion, no kit required | ||
| Hydrogen Compatibility | Suitable for up to 20% H₂ blend | ||
| CH Flow Temperature Range | 25 – 80 °C (adjustable) | ||
| Max System Pressure | 3 bar | ||
| Electrical Supply | 230 V / 50 Hz / single phase | ||
| Dimensions (H × W × D) | 700 × 390 × 285 mm | ||
| Weight | 28 kg | ||
| Minimum Cupboard Depth | 290 mm | ||
| Condensate Trap | Pre-heated siphonic (anti-freeze) | ||
| Filling System | EasyFill permanent filling link | ||
| Controls Compatibility | OpenTherm; Baxi uSense (optional); Nest, Hive & other OT thermostats | ||
| Cylinder Compatibility | Baxi cylinders; Megaflo Eco range | ||
| Warranty | 7 years parts & labour (registration required within 30 days) | ||
