Cubigel NUT55CAb Hermetic Compressor – 1/5 HP, R290, LBP 264 W

Cubigel NUT55CAb is a 1/5 HP hermetic reciprocating compressor made for commercial refrigeration appliances such as small freezers, ice cream cabinets and sub-zero display cabinets. It runs on R290 (propane); with a displacement of 5.5 cm³ it delivers a cooling capacity of 264 W (901 BTU/h) at ASHRAE LBP conditions.

R290 Propane LBP Compressor: For Small Freezers and Ice Cream Cabinets

Built on the U series body, the NUT55CAb draws low current thanks to its RSCR (run capacitor) motor and operates efficiently with COP 1.80 at LBP ASHRAE conditions. Its fan-cooled body is designed for capillary tube systems. Propane has a GWP of 3; it is a suitable option for low-charge systems that are not affected by F-Gas restrictions.

Key Technical Specifications and Equipment

• Brand / Model: Cubigel NUT55CAb · U series
• Refrigerant: R290 (propane) · explosion safety approved to EN 60335-2-34 for R290 and R600a
• Application: LBP (low back pressure) · evaporating −40 … −10 °C
• Displacement: 5.50 cm³ · bore 21.99 mm · stroke 14.50 mm
• Motor: RSCR · locked rotor current (LRA) 5.9 A · max. continuous current 1.55 A
• Power supply: 220-240 V / 50 Hz single-phase · operating range 187-255 V
• Cooling: fan-cooled · expansion: capillary tube
• Oil: ISO VG 10 ester, 200 cm³
• Tube inner diameters: service Ø6.2 · suction Ø6.2 · discharge Ø4.9 mm
• Dimensions: height 173.5 mm · base 204 × 158 mm (228 mm with terminal box)
• Mounting holes: 6 × Ø16 (170 × 70 mm)
• Weight: 9.21 kg · max. ambient temperature 43 °C

Performance (ASHRAE, Condensing +55 °C)

ASHRAE: liquid, ambient and suction temperature 32 °C. At CECOMAF LBP conditions (−25 °C, liquid 55 °C) 196 W, 141 W power input, COP 1.39. Capacity decreases as the evaporating temperature drops; make your selection according to the target cabinet temperature.

Electrical Equipment (Manufacturer References)

• Run capacitor: 5 µF 400 V
• Relay: PTC K100 (200-240 V · 14 Ω)
• Overload protector: AE18FU (6.3 A · open / close 120 / 62 °C) or B65-135 (6.5 A · 135 / 61 °C)

• 🔥 R290 is a flammable refrigerant (class A3). Brazing, leak testing and charging must be carried out according to the rules for flammable refrigerants: a ventilated area, no ignition sources and compliance with charge limits are essential. This compressor is for R290 systems only.
• 🔧 When replacing: with the RSCR connection, the run capacitor and PTC relay are used together; compare the refrigerant, LBP class and mounting hole spacing of the old compressor with the dimension drawing.
• Application limit: This model is LBP and is for capillary tube systems — it is not used in positive-temperature cooler (HBP) applications.