Atlas Copco 0830100809 (S245-112A09) Safety Valve for ZR 160-275

Description

The 0830100809 safety valve is the application safety valve of the Atlas Copco ZR 160–275 oil-free screw compressor series, identified under the designation S245-112A09. This page covers the complete Atlas Copco 0830100809 safety valve as a single ordered unit, built under German origin marking and declared under customs tariff code 84814090. Every compressed air circuit that feeds a receiver or a separation tank depends on one final protective device, and on the ZR 160, ZR 200, ZR 250, and ZR 275 packages that device is ordered under the number 0830100809. When the regulating system stops controlling output and pressure climbs past its design limit, the safety valve is the last mechanical barrier between normal operation and damage to the pressure-bearing parts of the package. That is why Atlas Copco instruction books treat the valve as a scheduled inspection item and why a failed unit is always replaced as a complete valve rather than re-shimmed in the field.

This article walks through what the 0830100809 safety valve does inside the ZR 160–275 circuit, how the S245-112A09 designation maps onto the part, which machines in the series confirm the application, and how a correct replacement is selected, installed, and verified. The goal is that a maintenance planner or an independent workshop can order the 0830100809 valve with confidence, match it against the old unit, and put it back into service without guesswork. Every recommendation below applies to the 0830100809 unit and to no other valve variant.

What the 0830100809 Safety Valve Does in the Circuit

A screw compressor package is a closed pressure system. Air is compressed in the element, pushed through the oil separation stage, and stored either directly in the machine receiver or in an external tank. Every item in that chain, from the element housing to the cooler cores to the receiver shell, has a maximum allowable working pressure. The 0830100809 safety valve is fitted to the pressure-bearing section of the package and is set to open at a defined limit above the normal working pressure of the machine. On the ZR 160–275 packages, the 0830100809 valve is that final device.

Under ordinary conditions the 0830100809 valve stays closed. A spring holds the disc against the seat, and system pressure presses the disc from below without overcoming the spring force. If the regulating system fails in a loaded condition, or if the outlet is blocked while the element keeps compressing, pressure in the circuit rises. When it reaches the set point, the disc lifts, and air discharges through the valve outlet until the pressure falls back below the reseating level.

The cycle is entirely mechanical: no electrical signal, no solenoid, and no controller intervention are involved.

Because the valve acts as the final barrier, its condition is treated as a safety matter rather than a performance matter. A valve that has lifted many times, that has seated against contaminated air, or that has corroded internally can no longer open at its stamped set point or fail to reseat cleanly. Atlas Copco maintenance schedules therefore call for the 0830100809 valve to be checked at defined intervals and replaced when its integrity can no longer be guaranteed.

Application on the ZR 160–275 Series

The 0830100809 safety valve is not a general-purpose relief valve picked from a catalogue shelf. It is the application safety valve of the Atlas Copco ZR 160–275 series, and the application is confirmed for four machines in the family:

• ZR 160
• ZR 200
• ZR 250
• ZR 275

For a ZR 160, a ZR 200, a ZR 250, or a ZR 275 in standard build, 0830100809 is the number the parts list shows for this position. The ZR 160–275 series covers the larger frames of the Atlas Copco oil-free screw compressor range, where the compressed air leaves the stages at a working pressure that leaves no margin for an uncontrolled overpressure event. On each of these packages the 0830100809 safety valve is the unit specified for the pressure-bearing circuit, matched to the working pressure of the machine rather than selected by thread size or body appearance.

Confirmation follows the standard route. The machine model places the package inside the series, the serial number identifies the exact build configuration in the parts list, and the parts list entry names 0830100809 for the safety valve position. A valve from the same S245 family with a different variant suffix must not be fitted as a substitute, because the set pressure band encoded in that suffix belongs to a different application.

The S245-112A09 Designation

Alongside the Atlas Copco part number, this valve is identified under the designation S245-112A09. The S245 prefix corresponds to a well-established family of direct-loaded safety valves for compressed air service, produced with a brass body, an external thread connection, and a spring-loaded disc assembly with a manual lifting device. Valves in this family carry certification under CE, VdTÜV, and ASME schemes, and they are used across compressor packages and other pressurised air installations where a compact, high-flow relief valve is required.

The suffix that follows the S245 prefix, in this case -112A09, identifies the specific variant: the connection size, the set pressure band, and the certification variant of that individual valve. This is why two valves that look identical from the outside must never be treated as interchangeable without checking the suffix. A relief valve for a 7 bar package and one for a 13 bar package can share the same body casting and the same external thread, yet open at completely different pressures. That is why the 0830100809 number, not the appearance of the body, identifies the valve you order.

For ordering purposes, the practical rule is straightforward. The Atlas Copco part number 0830100809 and the designation S245-112A09 refer to the same valve, so either reference can be used to identify the unit, but the stamped marking on the valve body remains the final confirmation when the old part is compared with the new one.

Official Specifications of the 0830100809 Safety Valve

The values below are taken from the official Atlas Copco part data for the 0830100809 safety valve. Only confirmed figures are listed.

Three details in this table deserve a comment. First, the weight of 3.14 kg places the valve in the class of full-body brass relief valves rather than the small, light test cocks fitted to some auxiliary circuits, which matches its role as the primary relief device of the package. Second, the 315 mm overall length reflects the long threaded inlet and the full spring housing above it, so the installation position must leave this length free around the valve port. Third, customs tariff code 84814090 classifies the unit correctly as a safety or relief valve for pressure equipment, which simplifies cross-border clearance of the part. Every figure above is drawn from the official 0830100809 data sheet, so the table can be used directly for import paperwork and for the machine file.

Set Pressure and Valve Stamping

Atlas Copco instruction books for screw compressor packages state the safety valve effective opening pressure for each model and add a short instruction beside the table: check the stamping on the valve. That instruction exists because the set point of an individual valve lives on the valve itself, marked by the valve manufacturer, and the controller or the machine plate cannot substitute for it.

When a new 0830100809 safety valve arrives, read and record the stamped marking before installation. The marking identifies the set pressure at which the disc is specified to lift. The value must match the opening pressure documented for the machine in its instruction book, and it must also match the marking on the 0830100809 valve being replaced. If the stamped values differ, the valve is not the correct variant for that package, regardless of how well it fits the port.

The same rule applies on the S245-112A09 side of the designation. The variant suffix encodes the set pressure band, so a valve stamped for a different band is a different spare part even though the body and thread are the same. This is the single most common selection error with safety valves, and it is also the most dangerous one, because a valve set too high offers no protection at the design limit of the receiver, and one set too low will lift constantly during normal loading. With the 0830100809 valve the rule is simple: one variant suffix, one stamped set pressure, one application.

The 0830-1008 Valve Series in the Parts Programme

In the Atlas Copco numbering system, the 0830100809 safety valve belongs to a dense series of safety valve part numbers built on the 0830-1008 stem. Neighbouring numbers in this family, such as 0830100806, 0830100807, 0830100808, 0830100810, 0830100811, and 0830100812, cover relief valves with different connection sizes and set pressure bands for the wider compressor range. The 0830100809 position inside this series is fixed, so the neighbouring numbers are listed here for identification only, not as substitutes.

The existence of this series explains why the last digits of the part number matter as much as the valve’s appearance. The family shares castings, threads, and spring housings, so a photo of the old valve is rarely enough to identify the correct spare. The part number stamped or printed on the unit, cross-checked against the machine parts list, is the only reliable selector. When a workshop keeps several valves from this series, label the bins with the full part number and the stamped set pressure, never with thread size alone.

Why Safety Valves Are Replaced Rather Than Adjusted

A spring-loaded relief valve is a calibrated device, and the 0830100809 valve follows exactly the same logic as any direct-loaded relief valve in this class. The spring rate, the seat geometry, and the disc lift are matched so the valve opens within a tight tolerance of its set point and reseats without leaking. Once a valve has been in service, several mechanisms work against that calibration:

• Seat wear from repeated lifting leaves a leak path that lets pressurised air escape continuously.
• Corrosion or oil varnish between the disc and the seat can stick the valve shut, raising its effective opening pressure above the stamped value.
• Spring relaxation after many lift cycles shifts the set point downward, causing nuisance lifting during normal operation.
• Contamination on the moving parts can slow the lift, restricting the discharge capacity below the flow the package needs in an overpressure event.

None of these conditions can be corrected by tightening the adjustment screw in the field. A valve that fails a functional check is replaced as a complete unit, and the replacement is ordered to the same part number and the same stamped set pressure as the original. This is also why Atlas Copco supplies the 0830100809 safety valve as a sealed, pre-set unit rather than as a kit of parts.

Inspection and Testing Practice

Instruction books for Atlas Copco compressor packages include the safety valve among the items checked during regular service, and on the ZR 160–275 packages that valve is the 0830100809 unit. The check has two levels. The first is a functional check performed with the machine running: the valve lifting device is operated carefully, the disc should lift and snap back cleanly, and the discharged air should stop when the valve reseats. A valve that does not lift under the device, or that continues to blow after reseating, has failed the check.

The second level is the verification of the set point against the stamped marking and the instruction book value. If the machine has lifted the valve in service, if the valve has been stuck for an unknown period, or if the stamped value cannot be read any more, the valve is replaced. Regional pressure equipment rules can add their own, stricter periodic verification requirements, and those rules always take precedence over the service schedule.

A practical note for planners: record the stamped set pressure of every valve removed from a package in the machine’s service file. Over the life of a compressor this history makes the next replacement faster and removes any doubt about which variant the package was built with.

Installation Notes for the Replacement

Installing the 0830100809 safety valve is a short job, but a few points determine whether the valve will actually protect the package:

• Depressurise the machine fully and confirm zero pressure on the gauge before breaking the valve connection.
• Inspect the valve port and the sealing face. Old sealant, damaged threads, or a scored seat face must be corrected before the new valve goes in.
• Use the sealing method the port was designed for, a bonded seal or a suitable thread sealant, and avoid excessive thread compound that could migrate into the valve seat.
• Tighten the valve by the valve body, not by the spring housing or the lifting lever, and leave the discharge outlet oriented so escaping air cannot strike a person or a hose.
• Record the 0830100809 replacement, the stamped value, and the functional check result in the machine service file.
• After the machine is back in service, verify that the valve holds pressure without leakage at the outlet and record the replacement in the service log.

The manual lifting device on the S245 family body should remain accessible after installation. A lever buried against the canopy makes the periodic functional check impossible, which effectively removes the valve from the inspection schedule.

Compatibility Checks Before Ordering

Because the ZR 160–275 series shares its valve family with other Atlas Copco applications, complete the following checks before the order is placed. The machine model narrows the package to ZR 160, ZR 200, ZR 250, or ZR 275, and the serial number identifies the exact build in the parts list. The parts list entry confirms the 0830100809 number for the safety valve position, and the stamped marking on the old valve provides the second confirmation, covering set pressure and variant suffix. Where the machine has been modified, for example to a different working pressure, the parts list of the modification applies rather than the original build record.

The 0830100809 unit itself carries the German origin marking and the customs tariff code 84814090, so documentation for export clearance can be prepared directly from the official data. The valve is supplied as a complete assembly, with no loose parts to account for on receipt.

FAQ

Q: Which machines does the 0830100809 safety valve fit?

The valve is the application safety valve of the Atlas Copco ZR 160–275 series, and on those packages the relief position is ordered under 0830100809, with the application confirmed for the ZR 160, ZR 200, ZR 250, and ZR 275. The serial number of an individual machine confirms the exact build configuration in the parts list.

Q: Is 0830100809 the same valve as S245-112A09?

Yes. The Atlas Copco part number 0830100809 identifies the same safety valve that carries the S245-112A09 designation. The Atlas Copco number is the ordering reference; the S245-112A09 marking follows the valve family designation used by the valve maker.

Q: Can I set the opening pressure myself after installation?

No. The valve is supplied pre-set for its variant, and the set pressure is confirmed by the stamping on the body. Field adjustment of a safety valve voids its certification and removes the guarantee that the valve opens at the documented limit, so a valve with the wrong set point is replaced, not re-adjusted.

Q: The valve leaks a small amount of air at the outlet. Is that normal?

A continuous leak at the outlet means the disc is no longer seating cleanly. This is a failed valve even if the machine still builds pressure normally, and it must be replaced with the same 0830100809 part number to restore the sealed condition of the circuit.

Q: How do I confirm the set pressure of the valve I receive?

Read the stamping on the valve body and compare it with the safety valve opening pressure listed in the instruction book of the machine. Both values must agree with the marking on the valve that was removed.

Q: Does the 0830100809 valve need any maintenance of its own?

The 0830100809 valve itself is maintenance-free in the sense that it contains no serviceable parts. The maintenance activity around it is inspection: a periodic functional check with the lifting device, verification of the stamped set point, and replacement whenever the check is not passed.

Ordering the 0830100809 Safety Valve

The 0830100809 safety valve is supplied as one complete, pre-set relief valve with German origin marking, specified for the ZR 160–275 series. Orders placed with us are prepared against the official part data listed above, packed for industrial transport, and released with the customs tariff code 84814090 declared on the export paperwork. Each order line is booked under 0830100809 exactly as the parts list shows it. If you need the valve for a machine already in your fleet, send us the compressor model and serial number together with the stamped marking from the old valve, and we will confirm the match before the order is processed.

• Part number: 0830100809, equivalent designation S245-112A09
• Application: Atlas Copco ZR 160–275 series — confirmed for ZR 160, ZR 200, ZR 250, and ZR 275
• Description: SAFETY VALVE, complete pre-set unit
• Country of origin: DE
• Customs tariff code: 84814090
• Weight: 3.14 kg (3140 g)
• Dimensions: 315 × 65 × 65 mm
• Brass body, direct-loaded, external thread connection, manual lifting device
• Set pressure confirmed by stamping on the valve body; never field-adjusted
• Order against 0830100809 only; the variant suffix and the stamping must match the old unit
• Replacement only as a complete valve; match part number and stamped set pressure

Other Atlas Copco Valves Available

Additional Atlas Copco valves are available on request. See the table below, or contact us and we will look into your requirement.