Updated: Mar 11, 2020
Ever notice your hydraulic elevator acting a little sluggish in cold weather? The problem is likely because the hydraulic oil that operates the elevator is too cool and needs to be kept warm, ideally at a temperature range between 100 and 130 degrees Fahrenheit.
Hydraulic elevators work by forcing pressurized fluid through a valve into a steel cylinder located above or below ground. This pressure forces a piston to rise, lifting the elevator platform and car. When the elevator doesn’t run, the hydraulic oil cools down and becomes thick and gummy, which can cause rough starts, bumpy rides, leveling problems and unnecessary strain on equipment.
The temperatures outside or in the machine room can also impact oil temperature. If either environment is very cold, changes in oil viscosity are more apparent. When not in use, the oil within the elevator's tank will try to reach equilibrium between its temperature and that of its surrounding environment.
One way to keep the oil warm are tank heaters inside the oil tanks of hydraulic elevators. They heat and thin the oil to prevent rough starts and less-than-smooth operation. Heaters keep the hydraulic oil in your elevator at a consistently warm temperature with a built-in, fixed thermostat.
This thermostat controls the oil temperature so that it never falls below its optimal functioning level of at or around 100 degrees. If the thermostat of the oil dips down below 90 degrees, the thermostat closes and the tank heater engages. The tank heater will continue heating the oil until it gets to 110 degrees. At 110 degrees, the thermostat will open and the tank heater will stop heating the oil.
Ambient temperatures are just one of the building conditions that can affect elevator performance. To see a list of other factors, download the list from the National Elevator Industry, Inc.