OSO ACCU A200 200L Stainless Steel Buffer Tank for Heat Pumps
OSO ACCU A200 â 200L Stainless Steel Buffer Tank for Heat Pumps (SKU 11009745) â 199L (nominal 200L) stainless steel buffer tank  | NANOPUR insulation  | ErP B  | Dual flow/return connections  | Hydraulic coupling & balancing  | Anti-clocking protection  | Cool storage function  | G½" air vent + drain  | Wall brackets included  | Ă595 Ă 1,265mm  | 39 kg
Most air source heat pumps require a minimum flow rate to operate correctly. Without sufficient water volume, the pump can "clock" (short-cycle on and off), reducing efficiency and increasing compressor wear. A buffer tank adds system volume so the heat pump runs in longer, more efficient cycles. The buffer also supplies the heat energy required for defrost cycles and, for heating-cooling systems, stores cooled water during summer operation. The 200L A200 is designed for larger or more demanding systems â particularly useful for heat pumps above 10kW, whole-house multi-zone systems, or commercial-grade residential installations.
The OSO ACCU A200 is the largest model in the OSO ACCU domestic buffer tank range, providing 199 litres (nominal 200L) of system volume in a wider Ă595mm Ă 1,265mm column. Moving up to the larger diameter versus the A60/A100's 434mm footprint means the A200 can be accommodated in most residential plant rooms while delivering substantially more thermal mass â reducing short-cycling risk even on larger heat pumps running at partial load across a multi-zone system.
Like all ACCU tanks, the A200 is built from EVERLAST⢠titanium-alloyed stainless steel with ULTRAWELD⢠construction and NANOPUR⢠insulation â no enamel lining, no sacrificial anode, no periodic maintenance of protective coatings. Its ErP B rating confirms efficient standby performance (46W heat loss), and the dual flow/return connections on both sides offer the flexibility needed for complex primary/secondary circuit arrangements found in larger systems.
Key Features
Technical Specifications
| Specification | Detail |
|---|---|
| Brand / Range | OSO Hotwater / ACCU |
| Model | ACCU A200 |
| SKU / Product No. | 11009745 |
| Actual Volume | 199 litres |
| Nominal Capacity | 200 litres |
| Energy Rating (ErP) | B |
| Standby Heat Loss | 46W |
| Tank Material | EVERLAST⢠titanium-alloyed stainless steel |
| Construction | ULTRAWELD⢠â no enamel, no anode required |
| Insulation | NANOPUR⢠|
| Diameter (Ă) | 595mm |
| Height (H) | 1,265mm |
| Weight (empty) | 39 kg |
| Freight Volume | 0.48 dmÂł |
| Placement | Floor-standing (wall-mountable with included brackets) |
| Flow/Return Connections | Dual sets â flexible configuration |
| Air Vent Connection | G½" F (separate) |
| Drain Connection | Yes â factory fitted |
| Sensor Pocket | 1Ă for 6â8mm sensor |
| Wall Brackets | Included (corrosion-resistant) |
| Typical Applications | Air source heat pumps 10kW+, multi-zone systems, ground source, solar thermal, commercial-grade residential |
Frequently Asked Questions
The 200L A200 is appropriate for heat pump systems with outputs of approximately 10kW or more, multi-zone systems where many zones may be closed simultaneously (giving low overall flow rates during mild weather), or where the installer wants additional defrost margin for installations in colder or more exposed locations. As a general rule, 20â50L per kW of heat pump output is a common starting point for buffer sizing, though the exact volume must be calculated based on the specific heat pump's minimum flow rate, the minimum on-cycle time and the distribution system design. Always consult the heat pump manufacturer's documentation or an MCS-accredited designer.
This is a function of the surface-area-to-volume ratio and the NANOPUR insulation thickness. As a buffer tank gets larger in diameter, proportionally more volume is enclosed within the same insulated surface area â so the larger tank is actually more thermally efficient per litre of stored volume. The A200's larger Ă595mm diameter (versus 434mm for A60/A100) makes it inherently better insulated in relative terms.
Yes. The OSO ACCU A200 is compatible with any closed heating circuit â air source, ground source, solar thermal or hybrid systems. Its dual connection configuration and stainless steel construction make it compatible with all common system inhibitors and glycol concentrations typically used in ground source systems.
The A200 is designed primarily for larger domestic and light commercial installations. For higher-volume commercial buffer requirements, OSO also offers larger ACCU tanks (from 300L upward). If you are unsure which size buffer is appropriate for a commercial project, contact us for system design guidance.
Product Information
Product Information
Shipping & Returns
Shipping & Returns
OSO ACCU A200 200L Stainless Steel Buffer Tank for Heat Pumps
OSO ACCU A200 200L Stainless Steel Buffer Tank for Heat Pumps
OSO ACCU A200 â 200L Stainless Steel Buffer Tank for Heat Pumps (SKU 11009745) â 199L (nominal 200L) stainless steel buffer tank  | NANOPUR insulation  | ErP B  | Dual flow/return connections  | Hydraulic coupling & balancing  | Anti-clocking protection  | Cool storage function  | G½" air vent + drain  | Wall brackets included  | Ă595 Ă 1,265mm  | 39 kg
Most air source heat pumps require a minimum flow rate to operate correctly. Without sufficient water volume, the pump can "clock" (short-cycle on and off), reducing efficiency and increasing compressor wear. A buffer tank adds system volume so the heat pump runs in longer, more efficient cycles. The buffer also supplies the heat energy required for defrost cycles and, for heating-cooling systems, stores cooled water during summer operation. The 200L A200 is designed for larger or more demanding systems â particularly useful for heat pumps above 10kW, whole-house multi-zone systems, or commercial-grade residential installations.
The OSO ACCU A200 is the largest model in the OSO ACCU domestic buffer tank range, providing 199 litres (nominal 200L) of system volume in a wider Ă595mm Ă 1,265mm column. Moving up to the larger diameter versus the A60/A100's 434mm footprint means the A200 can be accommodated in most residential plant rooms while delivering substantially more thermal mass â reducing short-cycling risk even on larger heat pumps running at partial load across a multi-zone system.
Like all ACCU tanks, the A200 is built from EVERLAST⢠titanium-alloyed stainless steel with ULTRAWELD⢠construction and NANOPUR⢠insulation â no enamel lining, no sacrificial anode, no periodic maintenance of protective coatings. Its ErP B rating confirms efficient standby performance (46W heat loss), and the dual flow/return connections on both sides offer the flexibility needed for complex primary/secondary circuit arrangements found in larger systems.
Key Features
Technical Specifications
| Specification | Detail |
|---|---|
| Brand / Range | OSO Hotwater / ACCU |
| Model | ACCU A200 |
| SKU / Product No. | 11009745 |
| Actual Volume | 199 litres |
| Nominal Capacity | 200 litres |
| Energy Rating (ErP) | B |
| Standby Heat Loss | 46W |
| Tank Material | EVERLAST⢠titanium-alloyed stainless steel |
| Construction | ULTRAWELD⢠â no enamel, no anode required |
| Insulation | NANOPUR⢠|
| Diameter (Ă) | 595mm |
| Height (H) | 1,265mm |
| Weight (empty) | 39 kg |
| Freight Volume | 0.48 dmÂł |
| Placement | Floor-standing (wall-mountable with included brackets) |
| Flow/Return Connections | Dual sets â flexible configuration |
| Air Vent Connection | G½" F (separate) |
| Drain Connection | Yes â factory fitted |
| Sensor Pocket | 1Ă for 6â8mm sensor |
| Wall Brackets | Included (corrosion-resistant) |
| Typical Applications | Air source heat pumps 10kW+, multi-zone systems, ground source, solar thermal, commercial-grade residential |
Frequently Asked Questions
The 200L A200 is appropriate for heat pump systems with outputs of approximately 10kW or more, multi-zone systems where many zones may be closed simultaneously (giving low overall flow rates during mild weather), or where the installer wants additional defrost margin for installations in colder or more exposed locations. As a general rule, 20â50L per kW of heat pump output is a common starting point for buffer sizing, though the exact volume must be calculated based on the specific heat pump's minimum flow rate, the minimum on-cycle time and the distribution system design. Always consult the heat pump manufacturer's documentation or an MCS-accredited designer.
This is a function of the surface-area-to-volume ratio and the NANOPUR insulation thickness. As a buffer tank gets larger in diameter, proportionally more volume is enclosed within the same insulated surface area â so the larger tank is actually more thermally efficient per litre of stored volume. The A200's larger Ă595mm diameter (versus 434mm for A60/A100) makes it inherently better insulated in relative terms.
Yes. The OSO ACCU A200 is compatible with any closed heating circuit â air source, ground source, solar thermal or hybrid systems. Its dual connection configuration and stainless steel construction make it compatible with all common system inhibitors and glycol concentrations typically used in ground source systems.
The A200 is designed primarily for larger domestic and light commercial installations. For higher-volume commercial buffer requirements, OSO also offers larger ACCU tanks (from 300L upward). If you are unsure which size buffer is appropriate for a commercial project, contact us for system design guidance.
Product Information
Product Information
Shipping & Returns
Shipping & Returns
Description
OSO ACCU A200 â 200L Stainless Steel Buffer Tank for Heat Pumps (SKU 11009745) â 199L (nominal 200L) stainless steel buffer tank  | NANOPUR insulation  | ErP B  | Dual flow/return connections  | Hydraulic coupling & balancing  | Anti-clocking protection  | Cool storage function  | G½" air vent + drain  | Wall brackets included  | Ă595 Ă 1,265mm  | 39 kg
Most air source heat pumps require a minimum flow rate to operate correctly. Without sufficient water volume, the pump can "clock" (short-cycle on and off), reducing efficiency and increasing compressor wear. A buffer tank adds system volume so the heat pump runs in longer, more efficient cycles. The buffer also supplies the heat energy required for defrost cycles and, for heating-cooling systems, stores cooled water during summer operation. The 200L A200 is designed for larger or more demanding systems â particularly useful for heat pumps above 10kW, whole-house multi-zone systems, or commercial-grade residential installations.
The OSO ACCU A200 is the largest model in the OSO ACCU domestic buffer tank range, providing 199 litres (nominal 200L) of system volume in a wider Ă595mm Ă 1,265mm column. Moving up to the larger diameter versus the A60/A100's 434mm footprint means the A200 can be accommodated in most residential plant rooms while delivering substantially more thermal mass â reducing short-cycling risk even on larger heat pumps running at partial load across a multi-zone system.
Like all ACCU tanks, the A200 is built from EVERLAST⢠titanium-alloyed stainless steel with ULTRAWELD⢠construction and NANOPUR⢠insulation â no enamel lining, no sacrificial anode, no periodic maintenance of protective coatings. Its ErP B rating confirms efficient standby performance (46W heat loss), and the dual flow/return connections on both sides offer the flexibility needed for complex primary/secondary circuit arrangements found in larger systems.
Key Features
Technical Specifications
| Specification | Detail |
|---|---|
| Brand / Range | OSO Hotwater / ACCU |
| Model | ACCU A200 |
| SKU / Product No. | 11009745 |
| Actual Volume | 199 litres |
| Nominal Capacity | 200 litres |
| Energy Rating (ErP) | B |
| Standby Heat Loss | 46W |
| Tank Material | EVERLAST⢠titanium-alloyed stainless steel |
| Construction | ULTRAWELD⢠â no enamel, no anode required |
| Insulation | NANOPUR⢠|
| Diameter (Ă) | 595mm |
| Height (H) | 1,265mm |
| Weight (empty) | 39 kg |
| Freight Volume | 0.48 dmÂł |
| Placement | Floor-standing (wall-mountable with included brackets) |
| Flow/Return Connections | Dual sets â flexible configuration |
| Air Vent Connection | G½" F (separate) |
| Drain Connection | Yes â factory fitted |
| Sensor Pocket | 1Ă for 6â8mm sensor |
| Wall Brackets | Included (corrosion-resistant) |
| Typical Applications | Air source heat pumps 10kW+, multi-zone systems, ground source, solar thermal, commercial-grade residential |
Frequently Asked Questions
The 200L A200 is appropriate for heat pump systems with outputs of approximately 10kW or more, multi-zone systems where many zones may be closed simultaneously (giving low overall flow rates during mild weather), or where the installer wants additional defrost margin for installations in colder or more exposed locations. As a general rule, 20â50L per kW of heat pump output is a common starting point for buffer sizing, though the exact volume must be calculated based on the specific heat pump's minimum flow rate, the minimum on-cycle time and the distribution system design. Always consult the heat pump manufacturer's documentation or an MCS-accredited designer.
This is a function of the surface-area-to-volume ratio and the NANOPUR insulation thickness. As a buffer tank gets larger in diameter, proportionally more volume is enclosed within the same insulated surface area â so the larger tank is actually more thermally efficient per litre of stored volume. The A200's larger Ă595mm diameter (versus 434mm for A60/A100) makes it inherently better insulated in relative terms.
Yes. The OSO ACCU A200 is compatible with any closed heating circuit â air source, ground source, solar thermal or hybrid systems. Its dual connection configuration and stainless steel construction make it compatible with all common system inhibitors and glycol concentrations typically used in ground source systems.
The A200 is designed primarily for larger domestic and light commercial installations. For higher-volume commercial buffer requirements, OSO also offers larger ACCU tanks (from 300L upward). If you are unsure which size buffer is appropriate for a commercial project, contact us for system design guidance.
