Sauermann Si-51 Peristaltic Condensate Pump – Thermal Probe, 6 L/h, 12 m Head

Sauermann Si-51 Peristaltic Condensate Pump | SI51CE01UN23

The Sauermann Si-51 is a peristaltic condensate pump designed for air-conditioning units up to 8 kW. It uses two thermal probes (temperature differential detection) to activate automatically when the air conditioner turns on, with no float switch required.

⚠️ Important: The Si-51 is not compatible with reversible or inverter systems as it must not be used in continuous operation. For inverter or reversible systems, see the Sauermann Si-52.

Key Features

• Peristaltic pump — quiet, vibration-free, self-priming operation
• Temperature differential detection — 2 thermal probes, activates at ≥6°C differential
• Runs 4 minutes after temperature differential falls below 6°C
• 12 m maximum discharge head | 2 m maximum suction head
• 6 L/h constant flow rate (regardless of discharge or suction head)
• IP55 protection — suitable for unventilated areas
• ≤30 dBA — ultra-quiet operation
• Easy-open front panel — tool-free tube replacement
• Glass fuse replaceable in one step (standard 5×20 cartridge)
• Compact: L85 × W108 × H122 mm
• CE & UKCA certified | RoHS & WEEE compliant | Made in France

Technical Specifications

Kit Contents

• Peristaltic pump Si-51
• 1.7 m cable including 2 wires for power supply (P & N)
• 2 thermal probes with 3.5 m cable (red cap = ambient air, blue cap = fresh air)
• Easy 2-screw sliding plastic bracket
• Ø15 mm to Ø6 mm adaptor + sleeve (ACC00927)

Applications

• Wall-mounted split AC units up to 8 kW
• Ceiling suspended units
• Computer room air conditioning
• Ducted systems
• Ideal for dusty or chemical environments (bakeries, hairdressers, hotels)

Si-50 vs Si-51 vs Si-52 — Which Do I Need?

PE-Series Spare-Part Compatibility

Use the spare parts specified for the pump family: PE5001 and PE5002 are for the PE-5000 / PE-5100 / PE-5200 range, while ACC00954 and ACC00953 are for the Si-50 / Si-51 / Si-52 range.

Compatible Accessories

• ACC00954 — Replacement head for Si-50, Si-51, Si-52
• ACC00953 — Replacement hose for Si-50, Si-51, Si-52
• ACC00927 — Multi-diameter reducing adaptor (Ø15 mm to Ø6 mm)
• ACC00919 — 6× self-sealing fittings for Ø6 mm (1/4") hose
• ACC00909 — Clear PVC hose Ø6 mm (5m)
• ACC00910 — Clear PVC hose Ø6 mm (50m)
• Browse all Condensate Pump Accessories

Also in the Sauermann Peristaltic Range

• Sauermann Si-50 — compressor signal detection, not for inverter/reversible
• Sauermann Si-52 — float switch detection, compatible with inverter/reversible

Frequently Asked Questions

Can I use PE-5100 spare parts (tubes, heads) on the Si-51?

No. The replacement heads (ACC00954) and hoses (ACC00953) for the Si-50/51/52 are not backward-compatible with the PE series. Use the PE-series replacement parts specified for the PE-5100, or the Si-series parts specified for the Si-51.

Can the Si-51 be used with inverter or reversible AC systems?

No. The Si-51 must not be used in continuous operation and is incompatible with reversible and inverter systems. Use the Si-52 instead.

What is the difference between the Si-51 and the Si-50?

The Si-50 uses compressor live signal detection. The Si-51 uses thermal probes (temperature differential) and activates automatically based on temperature change rather than a wired compressor signal.

Does the Si-51 work on UK 230 V supply?

Yes. The Si-51 runs on 230 V~ 50/60 Hz standard UK mains supply.

Browse our full range of peristaltic condensate pumps and Sauermann products.