The Onyx 90 Litre Indirect Stainless Steel Unvented Cylinder features an internal coil and is designed to work with gas, oil, or biomass boilers as the primary heat source. It also includes a 3kW immersion heater for backup heating.
Built to the highest standards, the Onyx Indirect Unvented Cylinder is constructed from premium Duplex stainless steel, ensuring excellent corrosion resistance and long-lasting durability. Suitable for a wide range of domestic and light commercial applications, it offers fast reheating and ample hot water delivery, making it an ideal choice for various projects.
Complete with G3 unvented kit that includes:
- 1x Thermowatt 3kW Immersion Heater
- 1x Zilmet Expansion Vessel
- 1x Caleffi Tundish
- 1x Caleffi 22mm Inlet Control Group Set (inc PRV)
- 1x Intatec Dual Control Stat
- 1x Honeywell Home 22mm 2 Port Motorised Zone Valve
- 1x Factory Fitted Caleffi 7 Bar / 90°C Temperature & Pressure Relief Valve
- 1x Factory Fitted Secondary Return (On 200L, 250L and 300L Models Only)




