Parts chaos costs HVAC companies more than they realize. Trucks out of stock = return visits. Warehouse full of parts nobody uses = cash sitting on shelves. Techs grabbing parts without logging them = mystery shrinkage. Here’s how to manage it. If you’re exploring this area, our Best HVAC Scheduling Software guide covers it in detail.
The Inventory Problem in HVAC
A typical 10-truck HVAC operation has $50,000-$80,000 in parts inventory across trucks and warehouse. We break this down further in Scaling an HVAC Business From 5 to 50 Trucks: A Roadmap. Without tracking:
- Trucks run out of common parts at the worst time (Friday afternoon, customer waiting)
- Warehouse has surplus of parts ordered for jobs that never happened
- Nobody knows what’s on which truck — techs borrow from each other and don’t replace
- Parts walk away — industry average shrinkage is 3-5% annually. On $80K inventory, that’s $2,400-$4,000/year in lost parts
- Emergency parts runs waste 30-60 minutes each. At 5 runs/week across 10 techs, that’s 25-50 hours/month of unbillable time
Inventory Management Options
Tier 1: FSM-Based Tracking (Simplest)
If you’re on Housecall Pro, Jobber, or ServiceTitan, track parts used per job. When a tech completes a repair, they log which parts were used. This gives you:
- Parts cost per job (for job costing)
- Usage patterns (which parts are used most)
- Basic depletion awareness (if Mike used the last 45MFD cap, you know it needs restocking)
How to do it: Add parts as line items on invoices/work orders. Review monthly to identify usage patterns and plan restocking.
ServiceTitan has the most advanced built-in inventory with truck inventory tracking, purchase orders, and transfer between locations. If you’re on ServiceTitan, this is your first choice.
Jobber and Housecall Pro track parts used per job but don’t have full inventory management. Supplement with a monthly truck audit spreadsheet.
Tier 2: Spreadsheet + Monthly Audits (Budget Option)
Create a spreadsheet with every truck’s standard inventory list. Monthly, each tech counts their truck stock and reports shortages. The parts manager restocks from the warehouse.
The spreadsheet includes:
- Part description
- Part number
- Standard quantity per truck
- Current quantity
- Reorder point
- Supplier and cost
This takes 30 minutes per truck per month. For a 5-truck shop, that’s 2.5 hours/month of admin time. Cheap and effective.
Tier 3: Dedicated Inventory Software (For Larger Operations)
PartsTech — Parts ordering and inventory management for automotive and HVAC. Search suppliers, compare prices, and order parts with a few clicks. Integrates with some FSM platforms.
Sortly ($49-$149/month) — Visual inventory tracking with barcode/QR scanning. Techs scan parts when they remove them from the truck. Real-time visibility into what’s on every truck.
inFlow ($89-$349/month) — Full inventory management with purchase orders, barcode scanning, warehouse management, and reporting. Designed for product businesses but adaptable for HVAC parts.
ServiceTitan Inventory — If you’re on ServiceTitan, their inventory module handles truck-level tracking, warehouse management, purchase orders, and replenishment alerts. Integrated into the FSM workflow.
Tier 4: Barcode/QR System (Maximum Control)
Barcode each part in your warehouse. When a tech takes a part, they scan it with their phone. The system deducts from inventory, assigns it to their truck, and alerts when reorder points are hit.
Setup cost: $200-$500 for a label printer and barcode scanner app. Ongoing: $50-$150/month for inventory software.
Best for: Shops with 15+ trucks where manual tracking breaks down and shrinkage is a real cost.
Truck Stocking Strategy
The Standard Truck Inventory
Build a standard inventory list for each truck. Every truck gets the same base kit, replenished weekly:
Capacitors: 5/25, 5/35, 5/40, 7.5/45, 10/50, 5/55 MFD (duals); 5, 10, 15, 25, 30, 40, 50 MFD (singles) — $200-$400 in caps Contactors: 30A and 40A, single and double pole — $80-$120 Motors: 1-2 universal condenser fan motors, 1 universal blower motor — $300-$500 Refrigerant: R-410A (1-2 jugs), R-22 if still servicing — $200-$400 Electrical: Thermostats, transformers, hard start kits, fuses, wire nuts — $200-$300 Gas components: Flame sensors, ignitors, gas valves — $200-$400 Filters: Common sizes for maintenance calls — $50-$100 Misc: Brazing supplies, nitrogen, refrigerant line fittings, drain treatment — $200-$300
Total standard truck stock: $3,000-$5,000
Restock Process
Weekly (preferred): Each tech submits a restock request (parts used that week). Parts manager pulls from warehouse and stages at the shop. Techs restock their trucks Monday morning.
Automated (ideal): When parts are logged on completed jobs in your FSM, the system generates a restock list. Parts manager fills it. No manual request needed.
Parts Run Reduction
Every parts run is 30-60 minutes of unbillable time. Reduce them by:
- Better truck stocking — carry parts for the top 50 repairs
- Pre-staging — if a job requires a specific part, have the warehouse pull it and stage it before the tech’s next morning
- Same-day delivery — establish accounts with local suppliers who offer delivery. The $10 delivery fee is cheaper than 45 minutes of tech time
Measuring Inventory Performance
Track these metrics monthly:
| Metric | Target |
|---|---|
| Parts runs per tech per week | Under 2 |
| First-time fix rate (parts-related) | Over 90% |
| Inventory shrinkage rate | Under 3% |
| Average parts-on-hand per truck | $3,000-$5,000 |
| Parts cost as % of revenue | 15-20% |
If parts runs are high, your trucks are under-stocked. If shrinkage is high, you need better tracking. If parts cost percentage is creeping up, negotiate with suppliers or review your markup.
Bottom Line
For shops under 10 trucks: track parts per job in your FSM + monthly truck audits. That’s enough.
For shops with 10+ trucks: add a dedicated inventory system (ServiceTitan Inventory, Sortly, or barcode scanning) to maintain visibility across a larger fleet.
For everyone: build a standard truck inventory, restock weekly, and track parts runs. Every parts run eliminated is 30-60 minutes returned to billable work. That’s real money.