100. SERVICING Utilities shall service and maintain any equipment they use on customer's premises and shall adjust thermostats, clocks, relays or time switches, if such devices must be so adjusted to provide service in accordance with the rate provision.105. ADJUSTMENTS The time switches used by the utility for controlling equipment such as water heaters and street lights shall be such quality that the timing mechanism may be adjusted so as to be accurate within ten (10) minutes per month. Time switches used by the utility for controlling street lighting or display lighting shall be inspected or operation observed at least once a month, and, if in error, adjusted and also adjusted upon complaint if found in error or when service interruptions cause them to be in error by one-half (1/2) hour or more. Time switches and control devices used by the utility for controlling off-peak appliances shall be inspected or operation observed periodically and adjusted if in error, and also adjusted upon complaint if found in error, or whenever service interruptions result in error of two (2) hours, or more, or in supplying service to off-peak appliances during peak periods.