Harlequin HeatStream 150 Indirect Electric PLUS Thermal Store
The Harlequin HeatStream 150 Indirect — sold as the HeatStream 150 Electric PLUS (model HS150EPLUS) — is a 150-litre open-vented thermal store engineered for properties where both electricity and a traditional primary heat source (such as a gas, oil or LPG boiler, or district heating) are available. It builds on the award-winning HeatStream Electric platform by adding a stainless steel primary coil rated to 14 bar, enabling pre-heating of the store from a central heating circuit in as little as 10 minutes. Like all HeatStream models, it is not subject to Part G of the Building Regulations, requires no G3 qualification and delivers mains-pressurised hot water with minimal maintenance — making it the definitive upgrade for flats, apartments and houses moving towards a hybrid or multi-source heating strategy.
Open-vented design means the HS150EPLUS is exempt from Part G of the Building Regulations and requires no G3-qualified engineer, no expansion vessel and no T&P relief valve — significantly reducing installation complexity and cost.
The primary stainless steel coil connects to a gas, oil, LPG or district heating circuit and pre-heats the full 150-litre store in as little as 20 minutes. The 3 kW + 3 kW immersion heater provides independent backup and boost heating.
The primary coil is rated to 14 bar, making it fully compatible with high-pressure district heating networks in addition to conventional domestic boiler circuits. Pressure drop at 15 l/min is just 107 mbar.
Use cheap overnight electricity or solar PV surplus via the immersion heaters, and top up with the boiler during peak demand. The 150-litre thermal mass buffers energy efficiently regardless of which source provides the heat.
1,315 mm tall with a 520 × 520 mm base — the PLUS model is only marginally heavier than the standard Electric at 39 kg empty (191 kg filled), and fits through a standard doorway or into a small airing cupboard without difficulty.
Polyethylene outer shell, polypropylene inner tank and stainless steel corrugated coils combine to deliver a corrosion-resistant, long-life product suitable for all UK water quality conditions including hard water and chloride-rich supplies.
All domestic hot water and primary circuit connections are on top of the unit. The primary coil connects via 22 mm compression fittings. The integrated heat source coil thermostat (pre-set 65°C, adjustable 45–75°C) controls primary circuit flow automatically.
A thermostatic mixing valve is supplied and pre-set to 45°C. Both heat sources can drive the store well above pasteurisation temperature, significantly reducing the risk of Legionella proliferation. No annual safety inspection is required.
| Model Code | HS150EPLUS |
| Storage Volume | 152 litres (nominal) |
| Dimensions (L × W × H) | 520 × 520 × 1,315 mm |
| Empty Weight | 39 kg |
| Filled Weight | 191 kg |
| ErP Energy Rating | B |
| Standing Heat Loss | 1.12 kWh/24h |
| Immersion Heaters | Dual element: 3 kW (short/boost) + 3 kW (long) |
| Heat-Up via Primary Coil (15–60°C at 15 l/min) | 20 minutes |
| Full Heat-Up via Long Immersion (15–60°C) | 156 minutes |
| Full Heat-Up via Both Immersions (15–60°C) | 78 minutes |
| Boost Reheat (45–60°C, short element) | 20 minutes (50 litres) |
| Hot Water at 15 l/min (60°C store) | 113 litres (no reheat) |
| Hot Water at 15 l/min (70°C store) | 180 litres |
| DHW Coil Max Operating Pressure | 3 bar |
| Primary Coil Max Operating Pressure | 14 bar |
| Primary Coil Pressure Drop at 15 l/min | 107 mbar |
| Primary Coil Connections | 22 mm compression |
| Primary Coil Thermostat (pre-set / range) | 65°C pre-set / adjustable 45–75°C |
| Max Storage Temperature | 85°C |
| Pipe Connections (DHW) | 22 mm (all on top) |
| Overfill Connection | G ¾" |
| Compatible Heat Sources | Gas boiler, oil boiler, LPG, district heating, heat pump |
| Outer Tank Material | Polyethylene |
| Inner Tank Material | Polypropylene |
| Coil Material | Stainless steel corrugated |
| MPN | HS150EPLUS |
Original: $2,459.10
-65%$2,459.10
$860.68More Images
Harlequin HeatStream 150 Indirect Electric PLUS Thermal Store
The Harlequin HeatStream 150 Indirect — sold as the HeatStream 150 Electric PLUS (model HS150EPLUS) — is a 150-litre open-vented thermal store engineered for properties where both electricity and a traditional primary heat source (such as a gas, oil or LPG boiler, or district heating) are available. It builds on the award-winning HeatStream Electric platform by adding a stainless steel primary coil rated to 14 bar, enabling pre-heating of the store from a central heating circuit in as little as 10 minutes. Like all HeatStream models, it is not subject to Part G of the Building Regulations, requires no G3 qualification and delivers mains-pressurised hot water with minimal maintenance — making it the definitive upgrade for flats, apartments and houses moving towards a hybrid or multi-source heating strategy.
Open-vented design means the HS150EPLUS is exempt from Part G of the Building Regulations and requires no G3-qualified engineer, no expansion vessel and no T&P relief valve — significantly reducing installation complexity and cost.
The primary stainless steel coil connects to a gas, oil, LPG or district heating circuit and pre-heats the full 150-litre store in as little as 20 minutes. The 3 kW + 3 kW immersion heater provides independent backup and boost heating.
The primary coil is rated to 14 bar, making it fully compatible with high-pressure district heating networks in addition to conventional domestic boiler circuits. Pressure drop at 15 l/min is just 107 mbar.
Use cheap overnight electricity or solar PV surplus via the immersion heaters, and top up with the boiler during peak demand. The 150-litre thermal mass buffers energy efficiently regardless of which source provides the heat.
1,315 mm tall with a 520 × 520 mm base — the PLUS model is only marginally heavier than the standard Electric at 39 kg empty (191 kg filled), and fits through a standard doorway or into a small airing cupboard without difficulty.
Polyethylene outer shell, polypropylene inner tank and stainless steel corrugated coils combine to deliver a corrosion-resistant, long-life product suitable for all UK water quality conditions including hard water and chloride-rich supplies.
All domestic hot water and primary circuit connections are on top of the unit. The primary coil connects via 22 mm compression fittings. The integrated heat source coil thermostat (pre-set 65°C, adjustable 45–75°C) controls primary circuit flow automatically.
A thermostatic mixing valve is supplied and pre-set to 45°C. Both heat sources can drive the store well above pasteurisation temperature, significantly reducing the risk of Legionella proliferation. No annual safety inspection is required.
| Model Code | HS150EPLUS |
| Storage Volume | 152 litres (nominal) |
| Dimensions (L × W × H) | 520 × 520 × 1,315 mm |
| Empty Weight | 39 kg |
| Filled Weight | 191 kg |
| ErP Energy Rating | B |
| Standing Heat Loss | 1.12 kWh/24h |
| Immersion Heaters | Dual element: 3 kW (short/boost) + 3 kW (long) |
| Heat-Up via Primary Coil (15–60°C at 15 l/min) | 20 minutes |
| Full Heat-Up via Long Immersion (15–60°C) | 156 minutes |
| Full Heat-Up via Both Immersions (15–60°C) | 78 minutes |
| Boost Reheat (45–60°C, short element) | 20 minutes (50 litres) |
| Hot Water at 15 l/min (60°C store) | 113 litres (no reheat) |
| Hot Water at 15 l/min (70°C store) | 180 litres |
| DHW Coil Max Operating Pressure | 3 bar |
| Primary Coil Max Operating Pressure | 14 bar |
| Primary Coil Pressure Drop at 15 l/min | 107 mbar |
| Primary Coil Connections | 22 mm compression |
| Primary Coil Thermostat (pre-set / range) | 65°C pre-set / adjustable 45–75°C |
| Max Storage Temperature | 85°C |
| Pipe Connections (DHW) | 22 mm (all on top) |
| Overfill Connection | G ¾" |
| Compatible Heat Sources | Gas boiler, oil boiler, LPG, district heating, heat pump |
| Outer Tank Material | Polyethylene |
| Inner Tank Material | Polypropylene |
| Coil Material | Stainless steel corrugated |
| MPN | HS150EPLUS |
Product Information
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Description
The Harlequin HeatStream 150 Indirect — sold as the HeatStream 150 Electric PLUS (model HS150EPLUS) — is a 150-litre open-vented thermal store engineered for properties where both electricity and a traditional primary heat source (such as a gas, oil or LPG boiler, or district heating) are available. It builds on the award-winning HeatStream Electric platform by adding a stainless steel primary coil rated to 14 bar, enabling pre-heating of the store from a central heating circuit in as little as 10 minutes. Like all HeatStream models, it is not subject to Part G of the Building Regulations, requires no G3 qualification and delivers mains-pressurised hot water with minimal maintenance — making it the definitive upgrade for flats, apartments and houses moving towards a hybrid or multi-source heating strategy.
Open-vented design means the HS150EPLUS is exempt from Part G of the Building Regulations and requires no G3-qualified engineer, no expansion vessel and no T&P relief valve — significantly reducing installation complexity and cost.
The primary stainless steel coil connects to a gas, oil, LPG or district heating circuit and pre-heats the full 150-litre store in as little as 20 minutes. The 3 kW + 3 kW immersion heater provides independent backup and boost heating.
The primary coil is rated to 14 bar, making it fully compatible with high-pressure district heating networks in addition to conventional domestic boiler circuits. Pressure drop at 15 l/min is just 107 mbar.
Use cheap overnight electricity or solar PV surplus via the immersion heaters, and top up with the boiler during peak demand. The 150-litre thermal mass buffers energy efficiently regardless of which source provides the heat.
1,315 mm tall with a 520 × 520 mm base — the PLUS model is only marginally heavier than the standard Electric at 39 kg empty (191 kg filled), and fits through a standard doorway or into a small airing cupboard without difficulty.
Polyethylene outer shell, polypropylene inner tank and stainless steel corrugated coils combine to deliver a corrosion-resistant, long-life product suitable for all UK water quality conditions including hard water and chloride-rich supplies.
All domestic hot water and primary circuit connections are on top of the unit. The primary coil connects via 22 mm compression fittings. The integrated heat source coil thermostat (pre-set 65°C, adjustable 45–75°C) controls primary circuit flow automatically.
A thermostatic mixing valve is supplied and pre-set to 45°C. Both heat sources can drive the store well above pasteurisation temperature, significantly reducing the risk of Legionella proliferation. No annual safety inspection is required.
| Model Code | HS150EPLUS |
| Storage Volume | 152 litres (nominal) |
| Dimensions (L × W × H) | 520 × 520 × 1,315 mm |
| Empty Weight | 39 kg |
| Filled Weight | 191 kg |
| ErP Energy Rating | B |
| Standing Heat Loss | 1.12 kWh/24h |
| Immersion Heaters | Dual element: 3 kW (short/boost) + 3 kW (long) |
| Heat-Up via Primary Coil (15–60°C at 15 l/min) | 20 minutes |
| Full Heat-Up via Long Immersion (15–60°C) | 156 minutes |
| Full Heat-Up via Both Immersions (15–60°C) | 78 minutes |
| Boost Reheat (45–60°C, short element) | 20 minutes (50 litres) |
| Hot Water at 15 l/min (60°C store) | 113 litres (no reheat) |
| Hot Water at 15 l/min (70°C store) | 180 litres |
| DHW Coil Max Operating Pressure | 3 bar |
| Primary Coil Max Operating Pressure | 14 bar |
| Primary Coil Pressure Drop at 15 l/min | 107 mbar |
| Primary Coil Connections | 22 mm compression |
| Primary Coil Thermostat (pre-set / range) | 65°C pre-set / adjustable 45–75°C |
| Max Storage Temperature | 85°C |
| Pipe Connections (DHW) | 22 mm (all on top) |
| Overfill Connection | G ¾" |
| Compatible Heat Sources | Gas boiler, oil boiler, LPG, district heating, heat pump |
| Outer Tank Material | Polyethylene |
| Inner Tank Material | Polypropylene |
| Coil Material | Stainless steel corrugated |
| MPN | HS150EPLUS |
