The EHC Compact All-In-One Electric System Boiler — 150L Ultimate Package is a factory-assembled, fully electric heating and hot water system that combines an 8kW, 10kW, 12kW or 15kW electric system boiler with a 150-litre indirect unvented stainless steel hot water cylinder in a single pre-plumbed, pre-wired unit. The cylinder and boiler are assembled on an 800×800mm footprint — designed to fit a standard airing cupboard — at a height of 1,081mm. The Ultimate Package adds an EHC Pro 4 magnetic filter, Adey MC1+ inhibitor and MC3+ cleaner, twin channel programmer, room thermostat and wiring centre — with EHC's target of installation in under 3 hours. Suitable for 1–2 bedroom homes, flats and apartments. No flue, no gas supply, no annual gas safety check required. 7–10 working day lead time. Free UK delivery.
8kW / 10kW / 12kW / 15kW
Boiler Output Options
150L
Cylinder Capacity
1081mm
Height
Pre-Plumbed
Factory Assembled
Grundfos
Pump
No Flue
Fully Electric
Range Overview — All Compact All-In-One Sizes
Cylinder
Boiler Outputs
Height
Footprint
Filled Weight
Typical Home
150L
8kW / 10kW / 12kW / 15kW
1081mm
800×800mm
211 kg
1–2 bed flat / house
170L
10kW / 12kW / 15kW
1209mm
800×800mm
235 kg
2–3 bed home
200L
10kW / 12kW / 15kW
1399mm
800×800mm
265 kg
3–4 bed home
250L
12kW / 15kW
1711mm
800×800mm
320 kg
4–5 bed home
300L
12kW / 15kW
1930mm
800×800mm
375 kg
5+ bed home
All models: 800×800mm footprint. 7–10 working day lead time. Free UK delivery.
What's in the Ultimate Package
Electric System Boiler — 8kW / 10kW / 12kW or 15kW (6-stage modulating, stainless steel heat exchanger, Grundfos pump, expansion vessel, auto-bypass, auto-air vent, digital display)
Note: radiators, radiator valves and system pipework are not included. Installation must be carried out by a G3 competent person (for the unvented cylinder) and a qualified electrician (for all electrical connections).
⚠ Installation Requirements: The unvented cylinder must be installed by a G3 competent person. All electrical connections must be made by a qualified electrician. A dedicated radial circuit with a suitably rated MCB is required for the boiler element. Minimum clearance: 150mm above unit for lid access; 450mm for internal access. Not suitable for gravity-fed (tank) hot water systems.
Key Features
100% Electric — No Flue, No Gas Pipework, No Annual Gas Safety Check
The Compact All-In-One is a fully electric system. No flue penetration, no combustion, no Gas Safe registration for the boiler work. Suitable for any property regardless of gas availability — ideal for off-grid locations, new builds subject to the Future Homes Standard, and properties converting from gas. Electric boilers are 100% efficient at point of use — every unit of electricity drawn converts directly into heat.
No flue requiredNo gas supply needed100% efficient
Boiler Output Choice: 8kW / 10kW / 12kW / 15kW — Match to Your Radiator Count
Available in 4 output options — 8kW / 10kW / 12kW / 15kW. Rule of thumb: add 1.5 kW for each radiator in the home when calculating the required output. The 15kW option suits the largest properties in this cylinder's target range. The boiler uses 6-stage modulating output — it does not run at full power continuously, modulating down to reduce electricity consumption during lower demand periods.
8kW / 10kW / 12kW / 15kW6-stage modulationMatch to rad count
Fully Pre-Plumbed and Pre-Wired — From Van to Done in Under 3 Hours
The Ultimate Package is supplied fully pre-plumbed and pre-wired. The cylinder arrives with zone valves, combination valve, T&P relief valve, tundish, DHW expansion vessel, wiring centre, programmer and room thermostat already connected and factory-assembled. EHC's headline claim is from van to done in under 3 hours for a qualified installer — significantly less than assembling and plumbing a boiler and cylinder separately.
EHC Pro 4 Magnetic Filter — Protects the System From Day One
The EHC Pro 4 magnetic filter is included in the Ultimate Package — fitted inline to the system pipework to capture magnetite (iron oxide particles) and other ferrous debris before they reach the heat exchanger or Grundfos pump. Magnetite is the primary cause of premature pump failure and boiler heat exchanger blockage in electric and gas heating systems. Inclusion of the filter from the outset protects both the warranty and long-term performance.
EHC Pro 4 filterMagnetite removalProtects pump + HX
Adey MC1+ Inhibitor and MC3+ Cleaner — Professional System Treatment Included
The Ultimate Package includes both Adey MC1+ system inhibitor and Adey MC3+ system cleaner. MC3+ is used during commissioning to flush installation debris, flux residues and manufacturing oils from the new system. MC1+ is dosed into the system after flushing and provides long-term corrosion protection — a requirement of most boiler warranties. Having both chemicals in the package removes a common last-minute site sourcing issue.
Twin Channel Programmer — Independent Heat and Hot Water Scheduling
The twin channel programmer controls the heating circuit and the hot water cylinder independently, allowing separate time schedules for each. In an S-plan configuration the homeowner can select heating only, hot water only, both, or neither — giving full control over energy use and comfort.
Twin channelS-plan readyIndependent heat + HW
Stainless Steel Unvented Cylinder with Polyurethane Insulation
The 150-litre indirect unvented cylinder is manufactured from stainless steel — corrosion-resistant and long-lasting. Polyurethane insulation minimises standing heat losses. Unvented design delivers mains-pressure hot water — suitable for power showers and modern high-flow fittings. Pre-fitted with 2× 22mm zone valves, combination valve, T&P relief valve, tundish and DHW expansion vessel.
The system boiler incorporates a Grundfos circulation pump — the industry benchmark for reliability and efficiency in residential heating systems. Quiet operation makes it suitable for installations in kitchens, utility rooms and airing cupboards adjacent to living spaces.
Grundfos pumpQuiet operation
Built-In Diagnostics — Digital Display with Fault Code Readout
The system boiler features a digital display showing flow temperature, return temperature, system pressure and current kW output stage. The power stage indicator shows whether the boiler is operating at one-third, two-thirds or full output. In the event of a fault, diagnostic fault codes are displayed directly on the front panel — reducing call-out time for service engineers.
The 150L cylinder and boiler combination is sized for 1–2 bedroom homes, flats and apartments up to approximately 6–7 radiators. As a rough sizing guide, add 1.5 kW per radiator to calculate the minimum boiler output required. Available boiler outputs for this cylinder: 8kW / 10kW / 12kW / 15kW. For properties at the upper end of the range, select the higher kW option.
What is the difference between the Basic and Ultimate Package?
The Basic Package includes the pre-plumbed boiler and cylinder core with zone valves. The Ultimate Package adds: EHC Pro 4 magnetic filter, Adey MC1+ inhibitor and MC3+ cleaner, twin channel programmer, room thermostat and wiring centre. EHC's target for the Ultimate Package is installation in under 3 hours.
Does this require a gas supply or a flue?
No — the Compact All-In-One is a fully electric system. No gas supply, no flue penetration and no combustion. Suitable for any property with single-phase electricity. No annual gas safety inspection is required.
What electrical supply does it need?
The boiler requires a single-phase 230V AC supply. A dedicated radial circuit with a suitably rated MCB is required for the boiler element. The 15kW boiler draws approximately 65A at full output — consult a qualified electrician for the correct circuit design.
Is the cylinder WRAS approved and G3 compliant?
The unvented cylinder is installed in accordance with G3 Building Regulations, which require installation by a G3 competent person. The cylinder incorporates a combination valve, temperature and pressure relief valve and tundish as mandated by G3. Always confirm the current WRAS and G3 status with the manufacturer before specifying.
Related Products
EHC Compact All-In-One 170L Ultimate
2–3 bed home — 10kW/12kW/15kW
EHC Compact All-In-One 200L Ultimate
3–4 bed home — 10kW/12kW/15kW
EHC Compact All-In-One 250L Ultimate
4–5 bed home — 12kW/15kW
EHC Single Boiler Pack
Accessories and controls for standalone EHC boilers
BTU & WATT Calculator
Room Dimensions
Room Type
Living Room
Bedroom
Kitchen
Bathroom
Conservatory
Hallway
Glazing Type
Single Glazed
Double Glazed
Triple Glazed
External Walls
0 Wall
1 Wall
2 Walls
3 Walls
4 Walls
Insulation Level
Poor
Average
Good (New Build)
Required Heating
0
Watts
0
BTUs
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