OSO ACCU A100 100L Stainless Steel Buffer Tank for Heat Pumps
OSO ACCU A100 — 100L Stainless Steel Buffer Tank for Heat Pumps (SKU 11003162) — 100L 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 | Ø434 × 1,168mm | 28 kg
Most air source heat pumps require a minimum flow rate to operate correctly. Without sufficient water volume, the pump can "clock" (short-cycle), reducing efficiency and increasing compressor wear. A buffer tank adds volume so the heat pump runs in longer, more efficient cycles. The buffer also provides the thermal mass for defrost cycles and, in heating-cooling systems, stores cooled water during summer operation. The 100L A100 suits heat pumps from approximately 5–12kW output in typical domestic systems.
The OSO ACCU A100 is the mid-range 100-litre model in the OSO ACCU stainless steel buffer tank series. It shares the same Ø434mm diameter column as the A60, making it a natural upgrade when a system assessment calls for more volume — for instance, where the heat pump output is higher, where fewer heating zones reduce average flow rates, or where the installer wants additional thermal mass for improved defrost performance.
Constructed from EVERLAST™ titanium-alloyed stainless steel with ULTRAWELD™ manufacturing and NANOPUR™ insulation, the A100 is inherently corrosion-free and requires no magnesium anode, no periodic recoating and no anti-freeze. Its ErP B energy rating confirms low standby losses (55W), ensuring the stored system volume stays at temperature with minimal energy input between heat pump cycles.
Key Features
Technical Specifications
| Specification | Detail |
|---|---|
| Brand / Range | OSO Hotwater / ACCU |
| Model | ACCU A100 |
| SKU / Product No. | 11003162 |
| Volume | 100 litres |
| Energy Rating (ErP) | B |
| Standby Heat Loss | 55W |
| Tank Material | EVERLAST™ titanium-alloyed stainless steel |
| Construction | ULTRAWELD™ — no enamel, no anode required |
| Insulation | NANOPUR™ |
| Diameter (Ø) | 434mm |
| Height (H) | 1,168mm |
| Weight (empty) | 28 kg |
| Freight Volume | 0.27 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 5–12kW, solar thermal, heating-cooling systems |
Frequently Asked Questions
The 100L A100 is appropriate where the heat pump output is higher (typically 7kW+), where the distribution system has fewer zones and therefore a higher risk of low flow rates during part-load operation, or where the installer wants additional thermal mass for more reliable defrost performance in cold climates. As a rough guide, 20–50L per kW of heat pump output is a common sizing approach — for an 8kW heat pump, 100L sits comfortably in range. Always refer to the heat pump manufacturer's minimum buffer volume specification and any MCS system sizing guidance.
No inhibitor or anti-freeze is required by the tank itself — the stainless steel construction is inherently corrosion-resistant. However, your heat pump's primary circuit may require a suitable inhibitor or glycol mixture per the heat pump manufacturer's instructions. Always follow the heat pump manufacturer's guidance on system water treatment.
Yes. The OSO ACCU A100 is compatible with any closed heating circuit — air source, ground source, solar thermal or hybrid systems. Its dual connections and neutral stainless steel construction make it suitable for use with all common system inhibitors and glycol concentrations.
The OSO ACCU stainless steel buffer tanks require minimal maintenance — there is no anode to replace, no enamel to inspect and no re-pressurisation of linings. Annual visual inspection of connections, the drain, and the air vent for leaks or corrosion is recommended as part of an annual heat pump service. System inhibitor concentrations should be checked annually per the heat pump manufacturer's schedule.
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OSO ACCU A100 100L Stainless Steel Buffer Tank for Heat Pumps
OSO ACCU A100 — 100L Stainless Steel Buffer Tank for Heat Pumps (SKU 11003162) — 100L 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 | Ø434 × 1,168mm | 28 kg
Most air source heat pumps require a minimum flow rate to operate correctly. Without sufficient water volume, the pump can "clock" (short-cycle), reducing efficiency and increasing compressor wear. A buffer tank adds volume so the heat pump runs in longer, more efficient cycles. The buffer also provides the thermal mass for defrost cycles and, in heating-cooling systems, stores cooled water during summer operation. The 100L A100 suits heat pumps from approximately 5–12kW output in typical domestic systems.
The OSO ACCU A100 is the mid-range 100-litre model in the OSO ACCU stainless steel buffer tank series. It shares the same Ø434mm diameter column as the A60, making it a natural upgrade when a system assessment calls for more volume — for instance, where the heat pump output is higher, where fewer heating zones reduce average flow rates, or where the installer wants additional thermal mass for improved defrost performance.
Constructed from EVERLAST™ titanium-alloyed stainless steel with ULTRAWELD™ manufacturing and NANOPUR™ insulation, the A100 is inherently corrosion-free and requires no magnesium anode, no periodic recoating and no anti-freeze. Its ErP B energy rating confirms low standby losses (55W), ensuring the stored system volume stays at temperature with minimal energy input between heat pump cycles.
Key Features
Technical Specifications
| Specification | Detail |
|---|---|
| Brand / Range | OSO Hotwater / ACCU |
| Model | ACCU A100 |
| SKU / Product No. | 11003162 |
| Volume | 100 litres |
| Energy Rating (ErP) | B |
| Standby Heat Loss | 55W |
| Tank Material | EVERLAST™ titanium-alloyed stainless steel |
| Construction | ULTRAWELD™ — no enamel, no anode required |
| Insulation | NANOPUR™ |
| Diameter (Ø) | 434mm |
| Height (H) | 1,168mm |
| Weight (empty) | 28 kg |
| Freight Volume | 0.27 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 5–12kW, solar thermal, heating-cooling systems |
Frequently Asked Questions
The 100L A100 is appropriate where the heat pump output is higher (typically 7kW+), where the distribution system has fewer zones and therefore a higher risk of low flow rates during part-load operation, or where the installer wants additional thermal mass for more reliable defrost performance in cold climates. As a rough guide, 20–50L per kW of heat pump output is a common sizing approach — for an 8kW heat pump, 100L sits comfortably in range. Always refer to the heat pump manufacturer's minimum buffer volume specification and any MCS system sizing guidance.
No inhibitor or anti-freeze is required by the tank itself — the stainless steel construction is inherently corrosion-resistant. However, your heat pump's primary circuit may require a suitable inhibitor or glycol mixture per the heat pump manufacturer's instructions. Always follow the heat pump manufacturer's guidance on system water treatment.
Yes. The OSO ACCU A100 is compatible with any closed heating circuit — air source, ground source, solar thermal or hybrid systems. Its dual connections and neutral stainless steel construction make it suitable for use with all common system inhibitors and glycol concentrations.
The OSO ACCU stainless steel buffer tanks require minimal maintenance — there is no anode to replace, no enamel to inspect and no re-pressurisation of linings. Annual visual inspection of connections, the drain, and the air vent for leaks or corrosion is recommended as part of an annual heat pump service. System inhibitor concentrations should be checked annually per the heat pump manufacturer's schedule.
Product Information
Product Information
Shipping & Returns
Shipping & Returns
Description
OSO ACCU A100 — 100L Stainless Steel Buffer Tank for Heat Pumps (SKU 11003162) — 100L 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 | Ø434 × 1,168mm | 28 kg
Most air source heat pumps require a minimum flow rate to operate correctly. Without sufficient water volume, the pump can "clock" (short-cycle), reducing efficiency and increasing compressor wear. A buffer tank adds volume so the heat pump runs in longer, more efficient cycles. The buffer also provides the thermal mass for defrost cycles and, in heating-cooling systems, stores cooled water during summer operation. The 100L A100 suits heat pumps from approximately 5–12kW output in typical domestic systems.
The OSO ACCU A100 is the mid-range 100-litre model in the OSO ACCU stainless steel buffer tank series. It shares the same Ø434mm diameter column as the A60, making it a natural upgrade when a system assessment calls for more volume — for instance, where the heat pump output is higher, where fewer heating zones reduce average flow rates, or where the installer wants additional thermal mass for improved defrost performance.
Constructed from EVERLAST™ titanium-alloyed stainless steel with ULTRAWELD™ manufacturing and NANOPUR™ insulation, the A100 is inherently corrosion-free and requires no magnesium anode, no periodic recoating and no anti-freeze. Its ErP B energy rating confirms low standby losses (55W), ensuring the stored system volume stays at temperature with minimal energy input between heat pump cycles.
Key Features
Technical Specifications
| Specification | Detail |
|---|---|
| Brand / Range | OSO Hotwater / ACCU |
| Model | ACCU A100 |
| SKU / Product No. | 11003162 |
| Volume | 100 litres |
| Energy Rating (ErP) | B |
| Standby Heat Loss | 55W |
| Tank Material | EVERLAST™ titanium-alloyed stainless steel |
| Construction | ULTRAWELD™ — no enamel, no anode required |
| Insulation | NANOPUR™ |
| Diameter (Ø) | 434mm |
| Height (H) | 1,168mm |
| Weight (empty) | 28 kg |
| Freight Volume | 0.27 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 5–12kW, solar thermal, heating-cooling systems |
Frequently Asked Questions
The 100L A100 is appropriate where the heat pump output is higher (typically 7kW+), where the distribution system has fewer zones and therefore a higher risk of low flow rates during part-load operation, or where the installer wants additional thermal mass for more reliable defrost performance in cold climates. As a rough guide, 20–50L per kW of heat pump output is a common sizing approach — for an 8kW heat pump, 100L sits comfortably in range. Always refer to the heat pump manufacturer's minimum buffer volume specification and any MCS system sizing guidance.
No inhibitor or anti-freeze is required by the tank itself — the stainless steel construction is inherently corrosion-resistant. However, your heat pump's primary circuit may require a suitable inhibitor or glycol mixture per the heat pump manufacturer's instructions. Always follow the heat pump manufacturer's guidance on system water treatment.
Yes. The OSO ACCU A100 is compatible with any closed heating circuit — air source, ground source, solar thermal or hybrid systems. Its dual connections and neutral stainless steel construction make it suitable for use with all common system inhibitors and glycol concentrations.
The OSO ACCU stainless steel buffer tanks require minimal maintenance — there is no anode to replace, no enamel to inspect and no re-pressurisation of linings. Annual visual inspection of connections, the drain, and the air vent for leaks or corrosion is recommended as part of an annual heat pump service. System inhibitor concentrations should be checked annually per the heat pump manufacturer's schedule.
