HVAC Truck Stock List: What to Carry and How to Restock

An HVAC truck stock list, in short: carry the parts that fix most no-cool and no-heat calls on the first visit (dual and single run capacitors, 30 and 40 amp contactors, igniters, flame sensors, fuses, a transformer, condensate parts, filters and a thermostat), the refrigerants you service, empty recovery cylinders and your tools. Set a minimum and maximum for each part and count weekly.

More on this topic: Running a trade business, every guide in one place.

Every trip to the supply house in the middle of a call costs an hour you can't bill and a customer who waits. A good truck stock list is how a small HVAC shop gets more repairs done on the first visit. Below is a list by category, the capacitor and electrical sizes worth carrying, the tools and safety gear, the rules for carrying refrigerant cylinders, and a simple min/max and restocking routine. Treat the quantities as a starting point: the right list depends on the brands and systems in your area, so build it from your own job tickets.

Key takeaways

• Stock for first-visit fixes: capacitors, contactors, igniters, flame sensors, fuses and condensate parts solve a large share of service calls.
• Carry capacitors by µF and voltage: 440V parts can replace 370V ones of the same rating; never the other way round.
• Refrigerant purchases are restricted to EPA Section 608 certified technicians, or an employer who shows the wholesaler written evidence of one.
• DOT's materials of trade exception covers gas cylinders up to 220 pounds gross each and 440 pounds of materials of trade per vehicle.
• Set a min and max for every part, review tickets at the end of each day and count the truck once a week.
• Swap seasonal stock: more capacitors and contactors in spring, more igniters and flame sensors in fall.

What should be on an HVAC truck stock list?

An HVAC truck stock list should cover the parts that fail most often, the supplies every visit uses, the refrigerants you service and the tools to install them. This is a starting list for a residential service truck; quantities are examples to adjust to your own job history:

Which capacitors and electrical parts should an HVAC truck carry?

Carry the capacitor sizes that match the equipment you see, by microfarads (µF) and voltage. A replacement should match the µF rating within the tolerance printed on the part, at the same or a higher voltage: a 440V capacitor can replace a 370V one, but not the other way round. Stocking only 440V parts keeps the bin smaller. A common starting set:

Which tools and safety gear belong on an HVAC service truck?

• Diagnostics: digital manifold or gauges with R-454B and R-32 pressure-temperature data loaded, clamp meter that reads capacitance, temperature clamps and probes, manometer, combustion analyzer.
• Evacuation and recovery: vacuum pump, micron gauge, recovery machine, charging scale, hoses with low-loss fittings. For A2L systems, use a recovery machine and vacuum pump their makers list for A2L refrigerants.
• Leak detection: an electronic leak detector that detects the A2L refrigerants you service, plus bubble solution.
• Brazing: torch kit, nitrogen with a flowmeter regulator, tubing cutters, flaring and swaging tools.
• Hand and power tools: nut drivers, screwdrivers, a cordless drill and impact driver, fin comb, coil brush, shop vac.
• Safety: safety glasses, gloves, a fire extinguisher, a first aid kit, a personal CO monitor for furnace work, a ladder rated for the load, and the safety data sheets for every refrigerant you carry.

What are the rules for carrying refrigerant on a service truck?

Refrigerant on a truck falls under two sets of rules: EPA controls who can buy and how it's handled, and the Department of Transportation controls how cylinders travel. The points that matter for a small shop, from the primary sources:

Within those limits, DOT says materials of trade aren't subject to the rest of its hazardous materials rules. If a truck regularly carries more than 440 pounds of cylinders, gases and other materials of trade, you're outside the exception: check the full rules before you load it. The simplest test is to weigh your full jugs, recovery cylinders and nitrogen on the charging scale and add them up.

A2L refrigerants add care, not paperwork. EPA lists R-454B for new equipment, not as a retrofit for R-410A systems, so never mix the two on the truck or in a system. Keep A2L cylinders upright and strapped, away from ignition sources, and let only trained techs work on A2L systems. Our R-454B transition guide covers the tools and training, and the EPA 608 certification guide covers the buying rules.

How do you set minimum and maximum stock levels?

Set a minimum (the count that triggers a refill) and a maximum (the count you refill to) for every part you stock. A simple rule: minimum equals what you use between restocks plus one spare, and maximum equals the minimum plus a normal refill. A worked example for a truck restocked once a week, with example usage:

Raise the numbers for peak season and lower them in the shoulder months. Parts that sat on the truck for 90 days without use go back to the shop shelf, and any part that caused a return trip goes on the list.

What is a good HVAC truck restocking routine?

A good restocking routine is short and happens on a fixed schedule. Copy this checklist:

1. End of each day: the tech reviews every completed ticket and writes down the parts used.
2. Before the first call next morning: pull those parts from the shop shelf and refill to max.
3. Once a week (Friday works): count every min/max item on the truck, note any shortages and restock.
4. Every week: check refrigerant weights, recovery cylinder fill levels and retest dates.
5. Every month: pull parts not used in 90 days and add any part that caused a supply-house run.
6. Every season: swap heating and cooling stock, and update quantities from last year's tickets.

Count return trips too. If a tech had to leave a job for a part, write down which part. Those notes, plus the end-of-day ticket review, are what make the list better each season. Fewer return trips also means fewer callbacks; see our guide to reducing callbacks. Running plumbers too? Our plumbing truck stock list follows the same routine.

Where CrewRobin fits

CrewRobin doesn't track inventory. It has no truck stock counts, doesn't take parts off a count when they're used, and doesn't reorder, so keep your min/max list in a spreadsheet or an inventory tool. What it does have is a price book of labor, parts and flat-rate services that you add to quotes, and My day, a phone-friendly web page where each tech adds notes and photos to the job, which gives you something to review at the end of the day. Tune-ups can follow a checklist per job type, like our HVAC maintenance checklist. See how it works for HVAC companies.

Frequently asked questions

What parts should an HVAC tech carry on the truck?

The parts behind most first-visit repairs: dual and single run capacitors, 30A and 40A contactors, a 24V transformer, blade and cartridge fuses, igniters and flame sensors, condensate float switches, common filters, a thermostat, filter driers and copper fittings, plus the refrigerants you service and empty recovery cylinders.

How many capacitors should be on an HVAC truck?

Start with two of each common size you see, such as 35/5, 40/5, 45/5 and 55/5 µF dual capacitors at 440V, plus single run capacitors for fans and compressors. Then adjust each size to what your tickets show you use between restocks.

Can a 440V capacitor replace a 370V capacitor?

Yes, if the µF rating matches within the tolerance on the part. A higher voltage rating is fine; a lower one isn't. Stocking only 440V parts keeps the truck simpler.

How much refrigerant can I carry on a service truck?

Under DOT's materials of trade exception, each gas cylinder can weigh up to 100 kg (220 lb) gross, and all materials of trade on the vehicle together up to 200 kg (440 lb). The cylinders must be marked and labeled and the driver told they're on board.

How often should you restock an HVAC truck?

Refill from the end-of-day ticket review every day, count every min/max item once a week, and review the whole list monthly and at each season change.

Put it to work this week

Put your parts and labor in a price book and quote from the truck. CrewRobin is free until your first 10 booked jobs, no card up front. Start free or see pricing.

Sources

Figures from outside CrewRobin were checked against these pages in October 2026. Most industry benchmarks come from vendors and agencies, so treat them as ranges, not rules.

• U.S. EPA: Refrigerant sales restriction (updated March 23, 2026)
• U.S. EPA: Section 608 test topics (cylinders, 80% fill, shipping labels)
• U.S. EPA: Emissions Reduction and Reclamation rule fact sheet (September 2024)
• U.S. EPA SNAP: Substitutes in residential and light commercial AC and heat pumps
• 49 CFR 173.6, Materials of trade exceptions (via Cornell LII, read October 2026)
• 49 CFR 180.209, Requirements for requalification of specification cylinders (via Cornell LII, read October 2026)