Actuator & Servo Motor Replacements
Upgrade paths for Siemens SKP gas valve actuators and SQS servo motors.
Installation Differences
Siemens SKP replacements (old → new) typically require specific AGA adapters. Be aware of changes in connection sides, position indicators, and impulse line heights. Always recalibrate damper/valve curves after replacement.
Replacement List
| Brand | Discontinued Model | End of Life | Official Replacement | Key Differences | Interchange? | Action / Advice |
|---|---|---|---|---|---|---|
| Siemens | SQS27… | Defective -> Replace | SQS37… | Official replacement. Check installation size/linkage. Recalibrate stroke. | Conditional | Order SQS37 + accessories. Keep old unit for parameter reference. |
| Siemens | SKP10.110B17 / B27 | Discontinued | SKP15.000E1 / E2 | Requires AGA64/AGA65 adapter. Connection side/Position indicator changes. | Conditional | Order Connector/Junction Box together. Check pulse tube height. |
| Siemens | SKP10.111B17 / B27 | Discontinued | SKP15.001E1 / E2 | Requires AGA64/AGA65 adapter. Connection side/Position indicator changes. | Conditional | Order Connector/Junction Box together. Check pulse tube height. |
| Siemens | SKP20.110B17 / B27 | Discontinued | SKP25.003E1 / E2 | Requires adapter. Verify connection side and impulse line. | Conditional | Order complete kit (Actuator + Adapter). |
| Siemens | SKP20.111B17 / B27 | Discontinued | SKP25.001E1 / E2 | Requires adapter. Verify connection side and impulse line. | Conditional | Order complete kit (Actuator + Adapter). |
| Siemens | SKP27.110B27 | Discontinued | SKP25.703E2 | Same as above. | Conditional | Verify connection side and impulse line. |
| Siemens | SKP27.111B27 | Discontinued | SKP25.701E2 | Same as above. | Conditional | Verify connection side and impulse line. |
| Siemens | SKP50.110B17 / B27 | Discontinued | SKP55.003E1 / E2 | Same as above. | Conditional | Verify connection side and impulse line. |
| Siemens | SKP50.111B17 / B27 | Discontinued | SKP55.001E1 / E2 | Same as above. | Conditional | Verify connection side and impulse line. |
| Siemens | SKP70.110B17 / B27 | Discontinued | SKP75.003E1 / E2 | Same as above. | Conditional | Verify connection side and impulse line. |
| Siemens | SKP70.111B17 / B27 | Discontinued | SKP75.001E1 / E2 | Same as above. | Conditional | Verify connection side and impulse line. |
| Siemens | SKL90.110C27 (Air Valve) | Discontinued | SKL25.003E2 | Connection side/Position indicator changes. Pulse tube height diff. | Conditional | Check pipe/cable entry direction to avoid spatial conflict. |
Priority Procurement & Maintenance Advice
- Siemens SKP Replacements: Order as a "Kit" containing the new actuator + the required AGA adapter (e.g., AGA64/AGA65). Ordering only the actuator often leads to installation delays.
- Program Matching: If the actuator is part of a modulating control loop, verify runtime parameters match the controller program.
- Recalibration: Always recalibrate the air/fuel ratio curve after replacing an actuator to ensure combustion efficiency and safety.