The Propane Chiller is a machine that works with a compression refrigeration circuit, designed for water cooling, used in air conditioning applications or equipment cooling.
Features of the propane Chillers:
- Compressors in propane chillers are generally of the reciprocating or screw type.
- Some compressors that work with R290, use the same polyester oils as the compressors with R134a.
- R290 has a high solubility with mineral oil and polyester oil. The Condenser is usually air cooled, and works with copper tubes and aluminum fins.
- The high pressure side of the propane chiller must withstand a minimum of 3.5 times the saturation pressure of propane at 70 ° C, that is, 87 bar.
- The low pressure side of the propane chiller must withstand 5 times the saturation pressure of propane at 20 ° C, ie 36.8 bar.
- Before installing the propane chiller, it is particularly important that a risk assessment is carried out, with respect to the intended position of the chillers.
- The propane chiller must have a leak detection and control system, which when activated, will carry the propane charge to a liquid receiver, and then will cut off the electrical supply to the cooler.
- The propane chiller has refrigerant release valves, in case of continuing overpressures.
- In a propane chiller, when abnormally high pressure is present, as a first option the R290 gas should be released to the low pressure side of the system, rather than released to the atmosphere.
- The propane chiller release valves must be installed at the highest point of each circuit of the capacitor bank.
- Propane chiller release valves must be easily accessible and clearly visible from a safe distance, thus alerting operators to the possible release of a flammable gas.
- If the pressure continues to increase, then the gas is released through a pressure relief valve; Each propane chiller refrigeration circuit must be equipped with a properly selected relief valve to release excess pressure.
- The valve must be mounted above the high pressure liquid receivers.
- Whenever possible, the discharge port on the valve should be directed to a safe location, away from any source of ignition, preferably in an upward direction, to avoid low-level propane build-up.
- In a propane chiller, periodic leak checks are particularly important.
- Four quarterly inspections are recommended each year, and record keeping should be carried out in accordance with regulations.
- Propane chillers can be used to generate ice water or brine, in air conditioning, process refrigeration, and commercial refrigeration applications.
- The refrigerant charge of a propane chiller can be 40 to 60% lower than other refrigerants.
- Propane chiller motor winding thermistors must be housed and wired separately from other electrical components.
- There is no mandatory limit on the amount of propane that can be used in an outdoor chiller.
- However, some manufacturers have adopted 25 kg as the upper limit for the amount of propane per circuit
What is the working pressure in the R290 chiller?
| Temperature °C | Pressure psig |
| -20°C | 35.8 psig |
| -18°C | 38.6 psig |
| -16°C | 41.6 psig |
| -14°C | 44.4 psig |
| -12°C | 47.5 psig |
| -10°C | 50.7 psig |
| -8°C | 54.24 psig |
| -6°C | 57.8 psig |
| -4°C | 61.6 psig |
| -2°C | 65.6 psig |
| 0°C | 69.7 psig |
| 2°C | 74. psig |
| 4°C | 78.6 psig |
| 6°C | 83.4 psig |
| 8°C | 88.3 psig |
| 10°C | 93.5 psig |
| 12°C | 98.9 psig |
| 14°C | 104.7 psig |
| 16°C | 110.5 psig |
| 18°C | 116.6 psig |
| 20°C | 122.9 psig |
| 22°C | 129.5 psig |
| 24°C | 136.4 psig |
Where to learn all about chillers?
We have prepared a complete training in chilled water installations with chillers.
