OSO ACCU A60 60L Stainless Steel Buffer Tank for Heat Pumps | NANOPUR Insulation
OSO ACCU A60 — 60L Stainless Steel Buffer Tank for Heat Pumps (SKU 11009165) — 60L (57L actual volume) stainless steel buffer tank | NANOPUR insulation | Dual flow/return connections | Hydraulic coupling & balancing | Anti-clocking protection | Cool storage function | G½" air vent + drain | Wall brackets included | Ø434 × 741mm | 18 kg | ErP C
Most air source heat pumps require a minimum flow rate to operate correctly — without sufficient water volume in the system, the heat pump can "clock" (short-cycle on and off repeatedly), which reduces efficiency, increases wear and can shorten compressor life. A buffer tank adds volume to the system so the heat pump always has adequate water to heat, allowing it to run in longer, more efficient cycles. A buffer tank is also essential for defrost mode — the tank provides the heat energy the pump needs to defrost its evaporator — and for cooling/heating systems where the buffer stores cooled water during summer operation.
The OSO ACCU A60 is a 60-litre stainless steel buffer tank designed for use with air source heat pumps and solar thermal systems. Built from OSO's EVERLAST™ titanium-alloyed stainless steel and welded using the ULTRAWELD™ process, it is inherently corrosion-resistant — unlike mild steel buffer tanks, it requires no sacrificial anode and no periodic re-pressurisation of protective coatings. NANOPUR insulation ensures minimal standby heat loss (44W) to keep the buffer volume at the right temperature with minimal energy input.
The A60 is the most compact tank in the OSO ACCU range, suited to smaller heat pump installations or where space is limited. Its slimline Ø434mm footprint allows it to fit alongside most domestic heat pump units in standard plant rooms, cupboards or utility spaces. Wall brackets are included, allowing the tank to be mounted on a wall where floor space is at an absolute premium — though it can equally stand on the floor.
Key Features
Technical Specifications
| Specification | Detail |
|---|---|
| Brand / Range | OSO Hotwater / ACCU |
| Model | ACCU A60 |
| SKU / Product No. | 11009165 |
| Actual Volume | 57 litres |
| Nominal Capacity | 60 litres |
| Energy Rating (ErP) | C |
| Standby Heat Loss | 44W |
| Tank Material | EVERLAST™ titanium-alloyed stainless steel |
| Construction | ULTRAWELD™ — no enamel, no anode required |
| Insulation | NANOPUR™ |
| Diameter (Ø) | 434mm |
| Height (H) | 741mm |
| Weight (empty) | 18 kg |
| Freight Volume | 0.18 dm³ |
| Placement | Floor-standing (wall-mountable with included brackets) |
| Flow/Return Connections | Dual sets — flexible configuration |
| Air Vent Connection | G½" F (separate) |
| Drain Connection | Yes — factory fitted |
| Sensor Pocket | 1× for 6–8mm sensor |
| Wall Brackets | Included (corrosion-resistant) |
| Typical Applications | Air source heat pumps, solar thermal, heating-cooling systems |
Frequently Asked Questions
The required buffer volume depends on the heat pump output, the number of heating zones, the minimum flow rate of the heat pump and the minimum on-cycle duration specified by the manufacturer. As a general guide, 20–50 litres per kW of heat pump output is a commonly used rule of thumb, though the correct sizing must be calculated for each installation. For a typical 5–10kW domestic heat pump with 2–3 zones, a 60L buffer is often sufficient; larger systems or fewer zones may require 100L or 200L. Always consult the heat pump manufacturer's guidance or MCS documentation for your specific system.
No. A buffer tank stores heating system water (the circuit fluid) at heating temperatures — it is not a domestic hot water (DHW) cylinder. It is used in the primary heating circuit to stabilise heat pump operation. A separate unvented or vented DHW cylinder (or thermal store) is still required to provide hot water to taps and showers.
Yes. The A60 comes with corrosion-resistant wall brackets so it can be mounted vertically on a wall — useful in plant rooms or cupboards where floor space is restricted. The tank can equally stand on the floor; both installations are supported.
Yes. The OSO ACCU A60 is suitable for use with heat pumps connected to underfloor heating, radiators, fan coil units or any closed heating distribution system. Its dual flow/return connections make it compatible with a wide variety of primary/secondary piping configurations.
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OSO ACCU A60 60L Stainless Steel Buffer Tank for Heat Pumps | NANOPUR Insulation
OSO ACCU A60 — 60L Stainless Steel Buffer Tank for Heat Pumps (SKU 11009165) — 60L (57L actual volume) stainless steel buffer tank | NANOPUR insulation | Dual flow/return connections | Hydraulic coupling & balancing | Anti-clocking protection | Cool storage function | G½" air vent + drain | Wall brackets included | Ø434 × 741mm | 18 kg | ErP C
Most air source heat pumps require a minimum flow rate to operate correctly — without sufficient water volume in the system, the heat pump can "clock" (short-cycle on and off repeatedly), which reduces efficiency, increases wear and can shorten compressor life. A buffer tank adds volume to the system so the heat pump always has adequate water to heat, allowing it to run in longer, more efficient cycles. A buffer tank is also essential for defrost mode — the tank provides the heat energy the pump needs to defrost its evaporator — and for cooling/heating systems where the buffer stores cooled water during summer operation.
The OSO ACCU A60 is a 60-litre stainless steel buffer tank designed for use with air source heat pumps and solar thermal systems. Built from OSO's EVERLAST™ titanium-alloyed stainless steel and welded using the ULTRAWELD™ process, it is inherently corrosion-resistant — unlike mild steel buffer tanks, it requires no sacrificial anode and no periodic re-pressurisation of protective coatings. NANOPUR insulation ensures minimal standby heat loss (44W) to keep the buffer volume at the right temperature with minimal energy input.
The A60 is the most compact tank in the OSO ACCU range, suited to smaller heat pump installations or where space is limited. Its slimline Ø434mm footprint allows it to fit alongside most domestic heat pump units in standard plant rooms, cupboards or utility spaces. Wall brackets are included, allowing the tank to be mounted on a wall where floor space is at an absolute premium — though it can equally stand on the floor.
Key Features
Technical Specifications
| Specification | Detail |
|---|---|
| Brand / Range | OSO Hotwater / ACCU |
| Model | ACCU A60 |
| SKU / Product No. | 11009165 |
| Actual Volume | 57 litres |
| Nominal Capacity | 60 litres |
| Energy Rating (ErP) | C |
| Standby Heat Loss | 44W |
| Tank Material | EVERLAST™ titanium-alloyed stainless steel |
| Construction | ULTRAWELD™ — no enamel, no anode required |
| Insulation | NANOPUR™ |
| Diameter (Ø) | 434mm |
| Height (H) | 741mm |
| Weight (empty) | 18 kg |
| Freight Volume | 0.18 dm³ |
| Placement | Floor-standing (wall-mountable with included brackets) |
| Flow/Return Connections | Dual sets — flexible configuration |
| Air Vent Connection | G½" F (separate) |
| Drain Connection | Yes — factory fitted |
| Sensor Pocket | 1× for 6–8mm sensor |
| Wall Brackets | Included (corrosion-resistant) |
| Typical Applications | Air source heat pumps, solar thermal, heating-cooling systems |
Frequently Asked Questions
The required buffer volume depends on the heat pump output, the number of heating zones, the minimum flow rate of the heat pump and the minimum on-cycle duration specified by the manufacturer. As a general guide, 20–50 litres per kW of heat pump output is a commonly used rule of thumb, though the correct sizing must be calculated for each installation. For a typical 5–10kW domestic heat pump with 2–3 zones, a 60L buffer is often sufficient; larger systems or fewer zones may require 100L or 200L. Always consult the heat pump manufacturer's guidance or MCS documentation for your specific system.
No. A buffer tank stores heating system water (the circuit fluid) at heating temperatures — it is not a domestic hot water (DHW) cylinder. It is used in the primary heating circuit to stabilise heat pump operation. A separate unvented or vented DHW cylinder (or thermal store) is still required to provide hot water to taps and showers.
Yes. The A60 comes with corrosion-resistant wall brackets so it can be mounted vertically on a wall — useful in plant rooms or cupboards where floor space is restricted. The tank can equally stand on the floor; both installations are supported.
Yes. The OSO ACCU A60 is suitable for use with heat pumps connected to underfloor heating, radiators, fan coil units or any closed heating distribution system. Its dual flow/return connections make it compatible with a wide variety of primary/secondary piping configurations.
Product Information
Product Information
Shipping & Returns
Shipping & Returns
Description
OSO ACCU A60 — 60L Stainless Steel Buffer Tank for Heat Pumps (SKU 11009165) — 60L (57L actual volume) stainless steel buffer tank | NANOPUR insulation | Dual flow/return connections | Hydraulic coupling & balancing | Anti-clocking protection | Cool storage function | G½" air vent + drain | Wall brackets included | Ø434 × 741mm | 18 kg | ErP C
Most air source heat pumps require a minimum flow rate to operate correctly — without sufficient water volume in the system, the heat pump can "clock" (short-cycle on and off repeatedly), which reduces efficiency, increases wear and can shorten compressor life. A buffer tank adds volume to the system so the heat pump always has adequate water to heat, allowing it to run in longer, more efficient cycles. A buffer tank is also essential for defrost mode — the tank provides the heat energy the pump needs to defrost its evaporator — and for cooling/heating systems where the buffer stores cooled water during summer operation.
The OSO ACCU A60 is a 60-litre stainless steel buffer tank designed for use with air source heat pumps and solar thermal systems. Built from OSO's EVERLAST™ titanium-alloyed stainless steel and welded using the ULTRAWELD™ process, it is inherently corrosion-resistant — unlike mild steel buffer tanks, it requires no sacrificial anode and no periodic re-pressurisation of protective coatings. NANOPUR insulation ensures minimal standby heat loss (44W) to keep the buffer volume at the right temperature with minimal energy input.
The A60 is the most compact tank in the OSO ACCU range, suited to smaller heat pump installations or where space is limited. Its slimline Ø434mm footprint allows it to fit alongside most domestic heat pump units in standard plant rooms, cupboards or utility spaces. Wall brackets are included, allowing the tank to be mounted on a wall where floor space is at an absolute premium — though it can equally stand on the floor.
Key Features
Technical Specifications
| Specification | Detail |
|---|---|
| Brand / Range | OSO Hotwater / ACCU |
| Model | ACCU A60 |
| SKU / Product No. | 11009165 |
| Actual Volume | 57 litres |
| Nominal Capacity | 60 litres |
| Energy Rating (ErP) | C |
| Standby Heat Loss | 44W |
| Tank Material | EVERLAST™ titanium-alloyed stainless steel |
| Construction | ULTRAWELD™ — no enamel, no anode required |
| Insulation | NANOPUR™ |
| Diameter (Ø) | 434mm |
| Height (H) | 741mm |
| Weight (empty) | 18 kg |
| Freight Volume | 0.18 dm³ |
| Placement | Floor-standing (wall-mountable with included brackets) |
| Flow/Return Connections | Dual sets — flexible configuration |
| Air Vent Connection | G½" F (separate) |
| Drain Connection | Yes — factory fitted |
| Sensor Pocket | 1× for 6–8mm sensor |
| Wall Brackets | Included (corrosion-resistant) |
| Typical Applications | Air source heat pumps, solar thermal, heating-cooling systems |
Frequently Asked Questions
The required buffer volume depends on the heat pump output, the number of heating zones, the minimum flow rate of the heat pump and the minimum on-cycle duration specified by the manufacturer. As a general guide, 20–50 litres per kW of heat pump output is a commonly used rule of thumb, though the correct sizing must be calculated for each installation. For a typical 5–10kW domestic heat pump with 2–3 zones, a 60L buffer is often sufficient; larger systems or fewer zones may require 100L or 200L. Always consult the heat pump manufacturer's guidance or MCS documentation for your specific system.
No. A buffer tank stores heating system water (the circuit fluid) at heating temperatures — it is not a domestic hot water (DHW) cylinder. It is used in the primary heating circuit to stabilise heat pump operation. A separate unvented or vented DHW cylinder (or thermal store) is still required to provide hot water to taps and showers.
Yes. The A60 comes with corrosion-resistant wall brackets so it can be mounted vertically on a wall — useful in plant rooms or cupboards where floor space is restricted. The tank can equally stand on the floor; both installations are supported.
Yes. The OSO ACCU A60 is suitable for use with heat pumps connected to underfloor heating, radiators, fan coil units or any closed heating distribution system. Its dual flow/return connections make it compatible with a wide variety of primary/secondary piping configurations.
