Equipment start-up following an extended shut down period

Here, we provide some basic guidance and specific system considerations for machinery, electrical installations and mechanical systems in commercial properties following extended shut down periods.

Our guidance for commercial property owners/building managers should not replace the defined maintenance start up processes and prescribed procedures of equipment/installation operation manuals or codes of practice.

A risk assessment should be carried out and documented before start up commences, and only qualified and authorised persons should be engaged in starting up machinery or electrical installations.

• Refer to the user manual for specific start up procedures.
• Ensure all critical spare parts and tools are present.
• Safely isolate the machine and lock off supplies to make it safe.
• Clean all accessible parts of the machine.
• Examine the machine for leaks and check that lubrication levels are sufficient.
• Check plugged-in electrical parts are securely connected and there is no loose or damaged wiring.
• With the power still isolated, check control panel switches and buttons are working properly.
• Ensure that the machine settings and parameters are correct or in ‘neutral’ so that no part of the machine can move unless the operator triggers it to move.
• Where possible, move rotating, pivoting and sliding parts manually and lubricate where required in line with the machine’s maintenance manual.

• Replace all guarding after the necessary checks have been completed and safely start the machine slowly in parts. If possible, verify each part is operating in turn before engaging the next part.
• Where applicable, check that battery back-up is still working and all necessary PLC-type programs have been retained.
• After start-up, listen for any abnormal noises, and feel for any excessive vibration.
• Recheck the machine for leaks.
• The initial release of moving parts or dust on electrical parts may cause a burning smell. Isolate the machine if any such smell persists.
• Safely isolate the machine if you not going to continue using it.

• Check all landing doors are secure and aligned.
• Make sure the lift can be called at each landing.
  
• Ensure the lift is level with each landing.

• Ensure the car doors close properly.
  
• Test the alarm and intercom.
  
• When the lift is in operation, ensure there is no excessive vibration or noise.

Switching high-power electrical devices (such as lifts, machinery, air conditioners and refrigerators) creates sudden, brief demands for power which can upset the steady voltage flow in electrical systems. These are known as ‘switching surges’, and can be severe enough to damage components; immediately or gradually. Some equipment may fail to start after a long period of rest but a surge could cause a lot of damage to electrical installations and to supply authority equipment that you cannot access or repair.

Undervoltages, overvoltages and overcurrents caused by switching surges can also damage insulation or cause insulation flashover (an unintended electric discharge over or around the surface of an insulator). Damage and flashovers can often lead to power system outages, eroded components and increased risk of fire.

• Inspect the cooling unit for signs of damage, cracks or new signs of corrosion. If any irregularities are noted, an appointment with your appointed HVAC service company should be arranged.
• Remove any temporary covers and clean the condenser unit, removing any leaves or debris that may have accumulated.
• Verify refrigerant lines and gas pressure. Most modern systems have a low pressure indicator. If the pressure in the system has been depleted, seek advice from your HVAC service company.
• Inspect the air filter and clean or replace as necessary.
• Ensure grills are free from debris.
• Remove any stagnant water that may have accumulated after defrosting.
• Ensure all drains are clear from obstructions.

• Ventilate internal areas. Open windows and doors to allow fresh air to circulate prior to turning the system back on, and close before starting up the system (running the system with windows and doors open will put it under increased stress).
  
• Turn on the system, gradually bringing it online. Allow the system to run for 20 minutes at a low load until you can feel the air being cooled/heated.
• Slowly increase/decrease the setpoint by a couple of degrees every hour until the desired conditions are achieved.
• Verify the thermostat is set to the correct temperature. This will depend on seasonal conditions (cooling in summer, heating in winter).
• Check the condenser is running. During summer, the air coming out of the top should feel warm as the warm air is being removed from the building.

If shut down for extended periods, steam boilers/systems can experience an introduction of condensate in the pipework. This can lead to potential water hammer hazards (caused by the introduction of steam into cold pipework that has not been sufficiently drained) which can cause injury to operating personnel and others working within the vicinity of the plant. Therefore, the following steps should be considered to minimise the hazard:

• Introduce steam into the cold pipework gradually to avoid the risk of thermal shock and to reduce the chance of water hammer.
• Ensure the pipework system is completely drained when cold, and pay attention to areas where condensate can collect; which might include sagging lengths of pipework, vertical legs, changes of slope, dead ends, etc.
• Steam traps to maintain them, in accordance with manufacturers’ instructions.
• Use isolating valves to permit the gradual warming of the system.

• Check compressor oil levels are correct.
• Ensure all compressors are well ventilated.
• Drain all dryers, traps, pipework and receivers of condensate.
• Ensure all filters are clean.

• Ensure air is completely vented from the system.