Sauermann SI-51 Peristaltic Condensate Pump for Air Conditioning Systems

Sauermann SI-51 Peristaltic Condensate Pump | SI51CE01UN23

The Sauermann SI-51 is a peristaltic condensate pump designed for all types of air conditioning units up to 8kW. It uses two thermal probes (temperature differential detection) to activate automatically when the air conditioner turns on — no float switch required. The SI-51 is the direct replacement for the discontinued Sauermann PE5100.

⚠️ 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
• 12m maximum discharge head | 2m 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 × H122mm
• CE & UKCA certified | RoHS & WEEE compliant | Made in France

Technical Specifications

Kit Contents

• Peristaltic pump SI-51
• 1.7m cable including 2 wires for power supply (P & N)
• 2 thermal probes with 3.5m cable (red cap = ambient air, blue cap = fresh air)
• Easy 2-screw sliding plastic bracket
• Ø15mm to Ø6mm adaptor + sleeve (ACC00927)

Applications

• Wall-mounted split AC units up to 8kW
• 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?

Replaces PE5100

The SI-51 is the direct successor to the discontinued Sauermann PE5100. Note: replacement heads (ACC00954) and hoses (ACC00953) for the SI-50/51/52 are not backward-compatible with the older PE series.

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 (Ø15mm to Ø6mm)
• ACC00919 — 6× self-sealing fittings for Ø6mm (1/4") hose
• ACC00909 — Clear PVC hose Ø6mm (5m)
• ACC00910 — Clear PVC hose Ø6mm (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

Is the SI-51 a direct replacement for the PE5100?

Yes. The SI-51 uses the same temperature differential (thermal probe) detection method as the PE5100 and is Sauermann's recommended direct replacement.

Can I use PE5100 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 older PE series. If your PE5100 head or tube fails, Sauermann recommends replacing the complete unit with an 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 230V supply?

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

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