OSO Delta GeoCoil DGC300 300L Heat Pump Cylinder

The OSO Delta GeoCoil DGC300 is a 300 litre indirect unvented heat pump cylinder engineered for maximum efficiency with award-winning Vacuum Insulation Panels (VIP) and NANOPUR foam insulation. This ErP A-rated cylinder features a massive 3.1 m² coil optimised for heat pumps up to 18 kW, delivering exceptional energy savings and SAP compliance for larger properties.

Key Features

• 300 litre capacity with 3.1 m² smooth scale-resistant coil for superior heat transfer from high-capacity heat pumps.
• Class-leading A-rated efficiency with standing heat loss of just 49W / 1.18 kWh/24hrs through advanced VIP + NANOPUR insulation.
• 25-year warranty on titanium-alloyed stainless steel tank ensures corrosion-free performance for decades.
• INCOTEC 3 kW immersion heater above coil acts as booster for rapid recovery and legionella protection.
• Digital thermostat with holiday mode and anti-legionella function plus thermistor probe compatibility for smart controls.
• Compact 595 mm diameter x 1750 mm height fits standard airing cupboards despite large capacity.
• Full factory-fitted G3 unvented kit including 24L expansion vessel, motorised valve, T&P relief valves and tundish.
• S & Y plan system compatible with flexible control options for heat pumps, boilers and hybrid systems.

Why Buy the OSO Delta GeoCoil DGC300?

The DGC300 delivers unrivalled energy retention - saving up to 400 kWh/year through its revolutionary insulation technology, potentially paying for the entire cylinder over its lifetime while meeting the strictest building regulations and SAP requirements.

Perfect for larger homes with heat pumps, its oversized coil and premium construction guarantee reliable performance with minimal maintenance and maximum hot water availability.

Suitable For

• Large family homes (4+ bedrooms) with high hot water demand and heat pump installations up to 18 kW.
• New build developments requiring A-rated cylinders for maximum SAP scores and low carbon compliance.
• Hybrid heating systems combining heat pumps with gas/oil boilers for backup and peak demand.
• Properties upgrading to renewable heating seeking future-proof, ultra-efficient hot water storage.

Technical Specifications

• Brand: OSO Hotwater
• Model: Delta GeoCoil DGC300 (Product code: 11009123 / 10221800)
• Type: Indirect unvented heat pump cylinder
• Capacity: 300 litres (279L actual volume)
• Energy Rating: A (ErP)
• Standing Heat Loss: 49W / 1.18 kWh/24hrs (EN12897)
• Dimensions: Ø595 mm x 1750 mm height
• Weight: 340 kg full / 63-67 kg empty
• Primary Coil: 3.1 m² smooth scale-resistant titanium alloy
• Heat Pump Compatibility: Up to 18 kW
• Immersion Heater: 3 kW INCOTEC (1 x 240V) above coil
• Thermostat: Digital 60°C setpoint with anti-legionella + holiday modes
• Expansion Vessel: 24 litres
• Max Pressure: 10 bar relief / 6 bar working
• Warranty: 25 years tank / 2 years components

Installation & Compliance

Factory-assembled with complete G3 unvented controls package including oversized expansion vessel, safety valves and thermistor ports for professional heat pump integration by qualified MCS/G3 installers.