The MAXI series is our class-leading commercial range of hot water calorifiers; built to the high standards of design and efficiency that is synonymous with OSO Hotwater products. The MAXI range has been manufactured with EVERLAST™ high-alloy stainless steel in combination with ULTRAWELD™ technology for optimal corrosion resistance. Not only is the MAXI range extremely efficient, with industry-leading performance it can also be modified according to customer requirements.

The MAXI GEOCOIL— MGC has been custom-made for maximum hot water production from heat pumps up to 40 kW (400 L = 25 kW / 600 / 1 000 L = 40 kW); with a large surface area; smooth-piped and scaleesistant heating coil. The units are also suitable for solar collectors up to 40 m². MAXI GEOCOIL has ultra-grade INCOTEC immersion heaters acting as a booster above the heating coil. This feature raises the temperature to increase capacity and prevent bacterial growth. The booster heaters also provide maximum safety if there are any operational problems with the energy source. The electric immersion heaters will raise the temperature to a higher level and are available from 3 to 9 kW, in single or three phase 230 or 400V . They are thermostat controlled with separate safety thermal cutout. Contactors are not required and the supply cable is connected directly to the thermostat assembly.

G3 Kits and expansion vessel include

Other sizes and specifications are available to order.

• Highly efficient DHW production from heat pump up to 40 kW
• Extreme operational safety with electric heater as booster / back-up
• 10 bar design pressure and class-leading corrosion resistance



SpecificationsUNITMGC 400 - 9kW   + HX 3.1 m²MGC 600 - 2 x 7.5kW HX 4,6 m²MGC 1000 - 2 x 7.5 + HX 7.0 m²
Product no.OSO
Product nameMGC 400 - 9 kW  + HX 3.1m²MGC 600 - 2 x 7.5kW + HX 4,6 m²MGC 1000 - 2 x 7.5kW + HX 7.0 m²
Diameter — ⌀mm5958001000
Height - Hmm217520302100
Weight emptykg95136225
Technical/ErP information
Capacity 40CLN / AN / AN / A
Thermostat set pointC707070
Heat loss-EN 12897watt96118141
Heat loss / 24 hrs - EN 12897kWh/day
AEC (energy consumption)kW/yearN/AN/AN/A
Energy efficiency%N/AN/AN/A
Tapping profile3XS–XXLN/AN/AN/A
Energy ratingA+–FCCC
Primary Heating PowerkW75135135
Primary coil sizeMins
Immersion Heating Power93x 52x 7.5
Heat-up time ΔT 55°C CoilMinsN/AN/AN/A
Heat-up time ΔT 55°C upper elementMinsN/AN/AN/A
Heat-up time ΔT 55°C lower elementMinN/AN/AN/A
Recovery time ΔT 55°C coil 70%MinsN/AN/AN/A
Recovery time ΔT 55°C upper element 70MinsN/AN/AN/A
Recovery time ΔT 55°C lower element 70%MinsN/AN/AN/A