Troubleshooting and Maintenance

Keeping your office trailer in good condition is the best way to ensure it works reliably for the duration of your lease. Some simple, periodic maintenance is required. Should something not work as expected, here are a few tips to help you quickly and easily get things back on track. Of course, if these don’t work, you can always request service and a WillScot technician will be dispatched to diagnose and resolve the issue.


Always use only a qualified electrician to hook up your building and verify that the correct voltage is being supplied after the power has been turned on.

  • All lights do not work
    • Is the main breaker on at the breaker panel?
    • Check that all other breakers are in the ‘on’ position.
    • Note: Certain types of breakers appear to be on but actually are off. Try switching them off and then on again.
  • Some lights come on, some do not
    • Check all switches. Check bulbs which may have loosened in transit. If bulbs are burned out, replace them (customer’s responsibility). If bulbs are in good condition and still don’t work, call for service.
  • All fluorescent lights are flickering
    • Light ballasts are cold; flickering usually stops after a few minutes.
  • In one of the light fixtures, both bulbs are flickering
    • Change one bulb at a time by removing and installing new bulb. If it does not resolve the problem, call for service.
  • No power in one of the receptacles
    • Check the GFI receptacle in the bathroom and reset if tripped.
    • Check breaker in the breaker box. If breaker is on and there is still no power, call for service.
  • Breaker keeps tripping in one of the receptacles
    • Are there too many cords plugged into the same receptacle causing an overload in the circuit?
  • Note: To operate building properly it must be grounded.

Hot Water Heater

  • Hot water heater must be filled with water before electricity is turned on!
  • If hot water heater is not operating once filled, check on/off switch on the heater and the breaker in the breaker box.

Air Conditioning

  • The customer is responsible for changing the air conditioning filters every 30 days.
  • Periodic cleaning the evaporator coil, the condenser coil and checking and filling HVAC refrigerant is also required.
  • Air conditioning maintenance should be performed by trained and qualified HVAC technicians only. Damages due to failure to perform these tasks will be the customer’s responsibility.

Central Air Conditioner (Mounted on front of building)

Air conditioner does not operate

  • Is the voltage correct? (220 volts)
  • Is the connection done properly?
  • Are there loose wires?
  • Check circuit breaker at breaker box.
  • Check safety switch located outside, adjacent to the A/C.
  • Check the external disconnect located outside, adjacent to the A/C.
  • Check the fuses in the external disconnect.
  • Note: Only certain A/C models have internal fuses.

A/C is running, but no air is coming out of diffusers

  • Open ceiling diffusers and/or registers.
  • Make sure there are no obstructions in the air louvers or grilles (located on front wall inside).
  • Make sure the filter is clean.

How to Change the A/C Filter

  • Turn thermostat to off position.
  • Turn off power at main breaker box.
  • Remove service door (center panel) located on front of building
  • Slide old filter out.
  • Slide new filter in (arrow up).
  • Replace service door.
  • Turn on power at main breaker box.
  • Turn on thermostat and set as desired.
  • Water dripping outside is normal, especially in very hot and humid weather conditions.
  • Note: The HVAC filter can be accessed by removing the corner screws of the center HVAC panel.

Window Air Conditioner

Air conditioner does not operate

  • Is voltage correct? (220 volts)
  • Is the hookup done properly?
  • Is the circuit breaker tripped?

Air conditioner does not cool as it should

  • Is the thermostat set correctly? The temperature may not be set low enough. Turn knob to lower setting.
  • The room may have been very hot when A/C was first turned on. Allow additional time for it to cool down.

Heat Pump Operation

Some buildings are equipped with heat pumps. Unlike a gas furnace which makes a lot of hot air, a heat pump takes a while to warm up. It’s best to let the heater run all night at a lower temperature instead of turning it off completely. This will also keep it from freezing up.

Cold Weather Operation

  • During above normal snowfall, it is important that any excessive accumulation of snow and ice is removed from the roof to avoid safety hazards or damage to the building. WillScot recommends that customers hire a professional to do such work as removing snow and ice may be dangerous as well as cause damage to the roof.
  • The customer is responsible for heat taping all exposed pipes under unit.
  • Do not disconnect the heat (electric) from the unit until the plumbing has been drained. If not drained, the pipes may freeze and then burst.