During extremely cold periods hydraulic elevators may not react as they would when the temperatures are above freezing. A buildings hydraulic elevator may not level correctly during the first few runs of the day or during periods of inactivity. A recommendation would be to leave the elevator at the lowest landing during slow periods [you will have less of the elevator parts exposed to the typically cold hoistway] and run the car a few times in the morning to get hydraulic fluid warmer. It is always recommended to have the elevator room at a reasonable temperature or add a room heater or a hydraulic tank heater. Warming the elevator room will avoid any issues with the elevator not leveling properly during periods of inactivity.
When hydraulic fluid is cold it is thicker or has a higher viscosity. When hydraulic fluid is warmer it is thinner or has less viscosity. For example honey has a higher viscosity than water. If you keep your elevator machine room warm your elevator will perform better during these periods of extreme cold. The elevator control valve is set for a certain oil viscosity and when it exceeds the tolerance levels the elevator may not react as it typically would under normal running conditions.
For more information on elevator maintenance and service please visit www.colleyelevator.com