TL;DR: A 38-person commercial HVAC service firm in Dallas runs 4,800 service calls a year across 22 vans. The first-time fix rate is 68%, which means roughly 1,536 jobs need a second visit, and 938 of those are because the technician did not have the part. Each return trip costs about $310 in labour, drive time and a lost billable slot: $291,000 a year. The vans carry an estimated $183,000 of parts between them, stocked according to what each technician personally ran out of last time, tracked in no system at all. Every input needed to predict the part was already recorded before the technician left the yard. We designed a four-stage agent that enriches each job with equipment history, predicts likely parts against nine years of repair records, checks the assigned van, and raises a pull ticket before departure. Running cost: $94 to $185 per month.
Tuesday, 2:40pm, Forty Miles Out
Luis is at a restaurant in Plano with a rooftop unit that stopped cooling on the hottest afternoon of the year. He has been on site for thirty-five minutes. The diagnosis took eight of them: a failed condenser fan motor, a common failure on that model at around nine years old.
He does not have the motor. He has two others, for different units, which he stocked in April because that was what he ran out of in March.
He calls dispatch. The part is in the warehouse, forty miles away, and it is now nearly three o'clock. The next available slot for a return visit is Friday morning. The restaurant has a dining room at 31 degrees and a Saturday booking sheet that is full.
The information needed to bring that motor was all present before Luis left the yard at seven that morning. The equipment record held the make, the model and the install date. The service history showed two prior visits to that unit. The customer's phone call, transcribed by the answering service, said the fan was making a noise and then stopped. The firm has replaced eleven condenser fan motors on that exact model in the past three years, all between eight and ten years of age.
Nothing joined those four facts together, so the van was loaded on the basis of what Luis remembered running short of five months earlier.
This is, when stated precisely, a parts distribution system whose forecasting model is twenty-two separate memories, whose inventory record is the back of each van, and whose reorder trigger is a technician standing in front of a broken unit forty miles from the warehouse. Luis did not decide to arrive unprepared. He loaded the van from memory because nobody had ever given him anything else to load it from.
The Company
Commercial HVAC service and maintenance, Dallas, Texas. Thirty-eight employees: 22 field technicians, 4 dispatchers, 5 office and accounts, 3 sales, 4 management. $9.4M annual revenue, split roughly 60% planned maintenance contracts and 40% reactive service calls. Customers are restaurants, small retail chains, medical practices and light industrial units across the Dallas-Fort Worth area.
Service calls last year: 4,800. First-time fix rate: 68%. The industry benchmark for a well-run commercial operation sits between 75% and 85%, and the firm has known its number is low for three years.
Return visits: approximately 1,536. Of those, the service manager estimates 61% were parts-related, which is 938 trips that happened because a technician arrived without something. The remainder were access problems, additional faults found, or work that genuinely needed two visits.
Cost per return trip: 1.5 hours of drive time and roughly an hour on site, at a loaded technician cost of $68 per hour, plus vehicle running costs, plus the billable slot that trip displaced. About $310 all in. Across 938 trips that is $290,780 a year spent driving to jobs the firm had already visited.
Expedited freight adds to it. When a technician discovers a part is needed and the customer is a restaurant in July, somebody pays for overnight shipping. Roughly 40% of parts-related returns involve an expedite premium averaging $85: another $31,900.
The vans hold an estimated $183,000 of parts between them. That figure is an estimate because nobody has counted. There is no van inventory system, no periodic stock take, and no standard kit. Each technician stocks what they personally ran short of, which means 22 vans carry 22 different interpretations of what is likely to break.
Two contracts were lost last year at renewal, both citing responsiveness. Neither customer mentioned parts. They mentioned waiting until Friday.
The pattern behind all of it: a firm that holds nine years of repair history on every model it services, and loads its vans from memory.
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