Each season can have a different effect on machines, motors, and elevator controllers. Be it electrical or mechanical, each season brings with it very different weather patterns which can ultimately have either a negative or positive effect on various parts which make up the complete elevator operation.
It’s important to anticipate these problems and plan for any eventualities. Here are some examples where extreme heat can negatively affect the operation of your elevators:
1. Machine Room Heat and Humidity Temperature Control:
If there is no machine room climate control, it can cause elevator failure or equipment damage in the room. Nobody likes to work in the summer heat & humidity, our elevators are no different. Keeping in mind that most high-rise buildings have the machine (equipment) room located on the roof of the building and we all know that hot air rises, hence we can anticipate that when outdoor temperatures are exceeding 30 degrees Celsius (90 degrees F), it will be much hotter as we increase in the building height. In addition, the equipment on its own expends energy in the form of heat which can lead to an overall increase in the room temperature.
It’s not just the temperature that can be of great concern, humidity has its own way of posing potential problems. Humidity, which is a form of moisture that can ultimately damage the hoist and governor ropes, or should excessive moisture reside on any of the controller electrical components, severe failure can become apparent.
This does not just refer to traction (roped) elevators. Hydraulic elevators which operate by the displacement of oil can have their own set of problems arising from extreme temperatures. As its integral that the temperature of the oil does not exceed the manufacturer's recommended settings, extreme heat can cause changes in the viscosity of the oil which will ultimately create erratic speed control.
Solution: Maintain a proper airflow with exhaust and distribution. This will entail the installation of an HVAC system and it’s recommended that a SPLIT unit would provide for the best results. Not only will the controlled temperatures allow for the best-operating conditions, but the HVAC unit will also remove any excessive humidity.
This work should only be conducted by a registered HVAC contractor with the supervision of an EDM-A licensed elevator mechanic.
2. Power Outages due to Heat and Humidity: Due to extremely hot and humid weather, there is always the potential for power outages which can create havoc if there are no provisions for emergency backup power. The end result can potentially shut down an elevator with trapped passengers, thus creating an immediate emergency.
Solution: The ultimate solution is to have some source of emergency backup power that will engage when the utility power is lost. Unfortunately, several buildings are not equipped so it is important to ensure that the in-car emergency communication is operating properly, as well as the emergency lighting device in the elevator cabin. The backup lighting should produce illumination for a minimum of four hours. These features will provide the Patrons with some form of comfort while they are waiting to be assisted and removed from the malfunctioned elevator.
Hydraulic elevators which operate via the transmission and pressure of oil can be retrofitted with an emergency device that allows for the respective elevator to lower itself to the main landing whereby the doors will then open allowing for Patrons to exit safely. This is referred to as a battery lowering device for hydraulic elevators.
3. Elevator hoistway Ventilation Problem: An elevator ventilation system operates through air intake slots at the car floor level where the air is drawn from the hoistway and discharged at the top of the car through an exhaust fan that discharges air back into the hoistway. In some cases, the ventilation fan capacity is not properly sized according to the car volume, so when it’s hot and humid, the ventilation system fails to clear the humidity from the elevator properly. In addition, all buildings have the potential to have “stacking effects’ in the elevator hoistway. This is can be more prevalent in higher buildings.
Solution: Make sure the ventilation fan capacity is correctly measured and the control system is properly operational. In most cases, this is simply accomplished via a key switch located in the car operating panel. The fan unit should be properly installed and designed for the purpose of an elevator car top exhaust fan. There are several different types of fan units installed in the industry and in most cases, the requirement for replacement is NOT included under the contractual agreement and there will be an extra charge imposed.
4. Moisture In Elevator Hoist Ropes by Heat and Humidity: The lifespan of any elevator hoisting rope when exposed to moisture will be drastically shortened and the replacement cost can be extremely high. In the summer months, when it’s hot and extremely humid, it takes little time for sisal cores to absorb surrounding humidity, degrade, and require replacement. Another overlooked form of moisture in the hoistway is simple condensation. Any rope hanging in a hot environment is naturally under the influence of heat and natural humidity. As ropes cycle above into the machine room, condensation can form rapidly on the rope surface if there is a drastic atmospheric change from hot to cold.
Solution: To minimize moisture damage, the Contractor should always follow manufacturer recommendations on lubrication. Lubricant is critical to overall rope performance as it can help increase rope traction, acts as a barrier to rust formation, and offers some corrosion protection to the outer wires as well. However, the best way to prevent moisture from affecting ropes is vigilance and addressing environmental conditions as quickly as possible after a problem is found.
If you do discover that you may require some assistance in regards to these matters, don’t hesitate to call Mark Render at 647-961-4984. It is always best to look after any potential problems before they become costly and very inconvenient. We at BH Elevator Consultants Inc are committed to keeping you from losing your cool this summer. Call us for an inspection and to review your summer elevator solutions before the heat gets you fired up!