The Complete HVAC Truck Stock List (2026): What Every Tech Should Carry

Every callback you eat because the right capacitor wasn't on the truck costs you an hour of windshield time and a chunk of customer trust. After twenty years around service trucks, the pattern is always the same: the techs who never run dry aren't lucky — they run a stock system. This is the list, category by category, with real quantities and the reorder points to hold.

Shortcut: this entire list exists as a free interactive tool. One tap loads it into your phone, and it tracks itself from there.

🚚 Open the Free Truck Inventory Manager →
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1. Run Capacitors — the backbone of summer

Caps cause more no-cool calls than any other single part. Carry dual-round 440V (they replace 370V, never the reverse) and cover the tonnage spread:

System size	Common dual cap	Carry
1.5 – 2 ton	30/5 or 35/5 MFD	2 each
2.5 ton	35/5 or 40/5 MFD	2 each
3 ton	40/5 or 45/5 MFD	2 each
3.5 – 4 ton	45/5, 50/5, 55/5 MFD	2 each
5 ton	60/5 or 70/5 MFD	1–2 each

Add singles for fan and blower duty — 5, 7.5, and 10 MFD 440V — plus two universal hard start kits. Always verify against the nameplate or the old cap; the table is a stocking guide, not a fitment chart. (Testing a suspect cap? Our free capacitor test tool gives you a pass/fail verdict from rated vs measured MFD using the ±6% rule.)

Stock up: OEM & universal capacitors ship same-day.

2. Contactors & relays

The second-most-replaced part on a residential truck:

30A single-pole, 24V coil — carry 3 (the residential workhorse)
40A two-pole, 24V coil — carry 3 (heat pumps, larger condensers)
Time delay relay — carry 2
SPDT fan relay, 24V — carry 2

If the contactor is pitted, the customer is one hot weekend from a stuck-closed compressor. Replace on evidence, not on failure. Browse contactors.

3. Motors — the judgment call

Motors are where truck space and dollars collide. The workable compromise: one universal condenser fan motor at 1/4 HP 825 RPM and one at 1/3 HP cover most residential condensers; add a 1/2 HP multi-speed blower if you run service in shoulder seasons. Set their minimum at zero — you carry one, and when it goes on a job, that evening it goes on the reorder. Keep a rundown of pairings in your head or use our blower HP calculator when sizing a swap.

4. Ignition & heating (don't wait for October)

Universal hot surface igniters (271-type) — 2. The single most common winter part.
Silicon nitride igniter kit — 1. Sturdier, increasingly standard.
Universal flame sensors — 2. Half of "furnace lights then dies" calls end here.
Thermocouples, 30" — 2, for standing-pilot equipment still in the field.
Adjustable pressure switch — 2, and limit switches L140 / L160 — 2 each.
Universal ignition control module — 1, min zero (pricier, reorder on use).

Shop igniters and flame sensors.

5. Electrical staples

40VA 24V transformers — 2 (shorted t-stat wire takes these out constantly)
3A blade fuses — 5+ (the cheapest callback insurance in the trade)
18/5 thermostat wire — a 250 ft spool
Basic 1H/1C thermostat — 2
60A pull-out disconnect — 1
Wire nuts, spade terminals, electrical tape — bulk

6. Condensate & water management

Condensate pump — 1 (min zero; reorder when it leaves the truck)
SS1-type float switches — 2 (code in more jurisdictions every year)
Pan tablets — a dozen; drop them on every maintenance

7. Consumables that save the day

Schrader cores (6+), service valve caps, thread sealant, zip ties by the bag. Zero glamour, maximum "finished the job without a supply-house run."

The quantities logic: reorder points, not guesses

Every quantity above pairs with a minimum — the reorder point. The rule from warehouse management works on a van shelf: when quantity hits the minimum, it goes on the order list that day, not when it hits zero on a rooftop at 4:50 PM. Cheap consumables get a min of 1–2; expensive singles (motors, pumps, control modules) get a min of zero and an ironclad reorder-on-use habit.

Stop tracking this on a whiteboard

The list above is already loaded into our free Truck Inventory Manager — pick the AC, Heating, or Full Service template and every part lands on your phone with quantities and minimums preset. Tap − when you use a part; when anything hits its minimum it goes amber and lands on your restock list; one button adds the whole restock to a cart. It saves on your device — no account, no email, nothing to install.