Harlequin HeatStream 150L Direct Electric Thermal Store
The Harlequin HeatStream 150 Direct (model HS150E) is a 150-litre open-vented thermal store designed to deliver mains-pressurised hot water in flats, apartments and electrically heated properties — without the complexity or regulatory burden of a traditional unvented cylinder. Because it operates on the open-vented thermal store principle, it is not subject to Part G of the Building Regulations in the UK and requires no G3 qualification for installation. With an ErP 'B' energy rating and a compact 520 mm × 520 mm square footprint, it is the ideal upgrade for modern airing cupboards and new-build apartments alike.
Open-vented operation means the unit bypasses Part G of the Building Regulations. Any competent heating engineer can install it — no G3 qualification, no expansion vessel, no T&P relief valve needed.
Supplied with a 3 kW + 3 kW dual-element immersion heater. The short boost element delivers 50 litres of hot water in just 20 minutes, perfect for morning demand peaks or off-peak tariff charging strategies.
Designed to maximise off-peak electricity tariffs and solar PV surplus energy. The large thermal mass stores cheap-rate energy efficiently, reducing running costs over time.
The square 520 × 520 mm base fits through a standard doorway and sits comfortably in a small airing cupboard. At 1,315 mm tall, it stores significantly more hot water within a smaller footprint than equivalent cylinders.
Outer shell in tough polyethylene resists transport damage; the inner tank is non-corrosive polypropylene, making it suitable even in hard or poor-quality water areas. Stainless steel corrugated coils deliver fast heat transfer.
Maintenance consists of a 6-monthly water top-up via the filling loop — no annual safety inspection is required. All connections are on top of the unit, simplifying installation and any future servicing visits.
The thermostatic mixing valve (supplied) is set nominally to 45°C for safe delivery, while the long immersion heater can raise store temperatures to pasteurise against Legionella risk when required.
Specifically engineered for apartments, flats, houses and bungalows. The simple overfill pipe can run externally or to an internal low-temperature waste — no specialist discharge arrangement required.
| Model Code | HS150E |
| Storage Volume | 152 litres (nominal) |
| Dimensions (L × W × H) | 520 × 520 × 1,315 mm |
| Empty Weight | 36 kg |
| Filled Weight | 188 kg |
| ErP Energy Rating | B |
| Standing Heat Loss | 1.12 kWh/24h |
| Immersion Heaters | Dual element: 3 kW (short/boost) + 3 kW (long), 27" + full-depth |
| Thermostat Pre-Set | Nominally 70°C (adjustable) |
| Full Heat-Up (15–60°C, long element) | 156 minutes |
| Full Heat-Up (15–60°C, both elements) | 78 minutes |
| Boost Reheat (45–60°C, short element) | 20 minutes |
| Hot Water Available at 15 l/min (60°C store) | 113 litres (no reheat) / 50 litres (with boost reheat) |
| Hot Water Available at 15 l/min (70°C store) | 180 litres |
| DHW Coil Max Operating Pressure | 3 bar |
| Max Storage Temperature | 85°C |
| Pipe Connections | 22 mm (all on top) |
| Overfill Connection | G ¾" |
| Outer Tank Material | Polyethylene |
| Inner Tank Material | Polypropylene |
| Coil Material | Stainless steel corrugated |
| Minimum Mains Flow (recommended) | 12 l/min at 1 bar dynamic pressure |
| Max Inlet Pressure | 3 bar (PRV recommended above this) |
| Typical Building Type | Flats, Apartments, Houses, Bungalows |
| MPN | HS150E |
Original: $2,151.37
-65%$2,151.37
$752.98More Images
Harlequin HeatStream 150L Direct Electric Thermal Store
The Harlequin HeatStream 150 Direct (model HS150E) is a 150-litre open-vented thermal store designed to deliver mains-pressurised hot water in flats, apartments and electrically heated properties — without the complexity or regulatory burden of a traditional unvented cylinder. Because it operates on the open-vented thermal store principle, it is not subject to Part G of the Building Regulations in the UK and requires no G3 qualification for installation. With an ErP 'B' energy rating and a compact 520 mm × 520 mm square footprint, it is the ideal upgrade for modern airing cupboards and new-build apartments alike.
Open-vented operation means the unit bypasses Part G of the Building Regulations. Any competent heating engineer can install it — no G3 qualification, no expansion vessel, no T&P relief valve needed.
Supplied with a 3 kW + 3 kW dual-element immersion heater. The short boost element delivers 50 litres of hot water in just 20 minutes, perfect for morning demand peaks or off-peak tariff charging strategies.
Designed to maximise off-peak electricity tariffs and solar PV surplus energy. The large thermal mass stores cheap-rate energy efficiently, reducing running costs over time.
The square 520 × 520 mm base fits through a standard doorway and sits comfortably in a small airing cupboard. At 1,315 mm tall, it stores significantly more hot water within a smaller footprint than equivalent cylinders.
Outer shell in tough polyethylene resists transport damage; the inner tank is non-corrosive polypropylene, making it suitable even in hard or poor-quality water areas. Stainless steel corrugated coils deliver fast heat transfer.
Maintenance consists of a 6-monthly water top-up via the filling loop — no annual safety inspection is required. All connections are on top of the unit, simplifying installation and any future servicing visits.
The thermostatic mixing valve (supplied) is set nominally to 45°C for safe delivery, while the long immersion heater can raise store temperatures to pasteurise against Legionella risk when required.
Specifically engineered for apartments, flats, houses and bungalows. The simple overfill pipe can run externally or to an internal low-temperature waste — no specialist discharge arrangement required.
| Model Code | HS150E |
| Storage Volume | 152 litres (nominal) |
| Dimensions (L × W × H) | 520 × 520 × 1,315 mm |
| Empty Weight | 36 kg |
| Filled Weight | 188 kg |
| ErP Energy Rating | B |
| Standing Heat Loss | 1.12 kWh/24h |
| Immersion Heaters | Dual element: 3 kW (short/boost) + 3 kW (long), 27" + full-depth |
| Thermostat Pre-Set | Nominally 70°C (adjustable) |
| Full Heat-Up (15–60°C, long element) | 156 minutes |
| Full Heat-Up (15–60°C, both elements) | 78 minutes |
| Boost Reheat (45–60°C, short element) | 20 minutes |
| Hot Water Available at 15 l/min (60°C store) | 113 litres (no reheat) / 50 litres (with boost reheat) |
| Hot Water Available at 15 l/min (70°C store) | 180 litres |
| DHW Coil Max Operating Pressure | 3 bar |
| Max Storage Temperature | 85°C |
| Pipe Connections | 22 mm (all on top) |
| Overfill Connection | G ¾" |
| Outer Tank Material | Polyethylene |
| Inner Tank Material | Polypropylene |
| Coil Material | Stainless steel corrugated |
| Minimum Mains Flow (recommended) | 12 l/min at 1 bar dynamic pressure |
| Max Inlet Pressure | 3 bar (PRV recommended above this) |
| Typical Building Type | Flats, Apartments, Houses, Bungalows |
| MPN | HS150E |
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Description
The Harlequin HeatStream 150 Direct (model HS150E) is a 150-litre open-vented thermal store designed to deliver mains-pressurised hot water in flats, apartments and electrically heated properties — without the complexity or regulatory burden of a traditional unvented cylinder. Because it operates on the open-vented thermal store principle, it is not subject to Part G of the Building Regulations in the UK and requires no G3 qualification for installation. With an ErP 'B' energy rating and a compact 520 mm × 520 mm square footprint, it is the ideal upgrade for modern airing cupboards and new-build apartments alike.
Open-vented operation means the unit bypasses Part G of the Building Regulations. Any competent heating engineer can install it — no G3 qualification, no expansion vessel, no T&P relief valve needed.
Supplied with a 3 kW + 3 kW dual-element immersion heater. The short boost element delivers 50 litres of hot water in just 20 minutes, perfect for morning demand peaks or off-peak tariff charging strategies.
Designed to maximise off-peak electricity tariffs and solar PV surplus energy. The large thermal mass stores cheap-rate energy efficiently, reducing running costs over time.
The square 520 × 520 mm base fits through a standard doorway and sits comfortably in a small airing cupboard. At 1,315 mm tall, it stores significantly more hot water within a smaller footprint than equivalent cylinders.
Outer shell in tough polyethylene resists transport damage; the inner tank is non-corrosive polypropylene, making it suitable even in hard or poor-quality water areas. Stainless steel corrugated coils deliver fast heat transfer.
Maintenance consists of a 6-monthly water top-up via the filling loop — no annual safety inspection is required. All connections are on top of the unit, simplifying installation and any future servicing visits.
The thermostatic mixing valve (supplied) is set nominally to 45°C for safe delivery, while the long immersion heater can raise store temperatures to pasteurise against Legionella risk when required.
Specifically engineered for apartments, flats, houses and bungalows. The simple overfill pipe can run externally or to an internal low-temperature waste — no specialist discharge arrangement required.
| Model Code | HS150E |
| Storage Volume | 152 litres (nominal) |
| Dimensions (L × W × H) | 520 × 520 × 1,315 mm |
| Empty Weight | 36 kg |
| Filled Weight | 188 kg |
| ErP Energy Rating | B |
| Standing Heat Loss | 1.12 kWh/24h |
| Immersion Heaters | Dual element: 3 kW (short/boost) + 3 kW (long), 27" + full-depth |
| Thermostat Pre-Set | Nominally 70°C (adjustable) |
| Full Heat-Up (15–60°C, long element) | 156 minutes |
| Full Heat-Up (15–60°C, both elements) | 78 minutes |
| Boost Reheat (45–60°C, short element) | 20 minutes |
| Hot Water Available at 15 l/min (60°C store) | 113 litres (no reheat) / 50 litres (with boost reheat) |
| Hot Water Available at 15 l/min (70°C store) | 180 litres |
| DHW Coil Max Operating Pressure | 3 bar |
| Max Storage Temperature | 85°C |
| Pipe Connections | 22 mm (all on top) |
| Overfill Connection | G ¾" |
| Outer Tank Material | Polyethylene |
| Inner Tank Material | Polypropylene |
| Coil Material | Stainless steel corrugated |
| Minimum Mains Flow (recommended) | 12 l/min at 1 bar dynamic pressure |
| Max Inlet Pressure | 3 bar (PRV recommended above this) |
| Typical Building Type | Flats, Apartments, Houses, Bungalows |
| MPN | HS150E |
