HPC Fire · Installation
HPC Forno de Pizza: First Firing + Curing Your Refractory Oven
The HPC Forno series oven (Forno, Villa, and Di Napoli) uses a refractory material that cures into a ceramic on first use. Rush the first firing and you crack the dome. Cure it correctly and the oven handles outdoor weather year-round, including freezing temps, for the life of the product.
By Ash · Updated November 10, 2026
What you need
- Seasoned hardwood (oak preferred, no bark)
- Butane lighter or long match
- Oven thermometer rated to 1200°F+
- Gas supply connected if using dual-fuel start
HPC Forno series specs
- Forno Series weight
- 445 lbs
- Villa Series weight
- 370 lbs
- Di Napoli weight
- 450 lbs
- Oven interior
- 29" wide × 30" deep
- Dome thickness
- 2.5"
- Hearth stone thickness
- 3" (refractory + insulating + reinforced refractory layers)
- Peak temperature (dual fuel)
- 1200°F+
- Neapolitan pizza hearth temp
- 625-650°F (reached in 20-30 min)
- Refractory max rating
- 2400°F
Step by step
First firing — gas only, low flame, 60 minutes
Start the gas burner at LOW flame only. Let the oven come up slowly. The refractory material needs time to shed any moisture it absorbed during manufacture/shipping — if that water flashes to steam too fast, it fractures the material.
Add wood after 60 minutes of gas warm-up
Once the oven is warm (hand-hold distance from the entry feels hot, not scorching), add a small piece of seasoned oak to the gas burner. The gas lights the wood automatically on HPC's dual-fuel design — "wood and gas are able to intersect with each other."
Build to cooking temp over 30-60 more minutes
With both fuels running, the oven climbs twice as fast as wood-only. Target 625-650°F on the hearth stone for Neapolitan pizza, which takes about 20-30 minutes TOTAL in a cured oven — on first firing give yourself the full 90 minutes from cold start.
Cool slowly — do not quench
After the cure firing, let the oven cool naturally overnight. Do NOT spray water on hot refractory. Do NOT open the door and force cool air in. The slow cool is as important as the slow warm-up.
Common mistakes
- Loading a full wood fire on day one. Full wood fire from cold is the fastest way to crack the hearth stone. The gas assist is specifically there for ramp-up — use it.
- Using wet or bark-covered wood. HPC specs: "Oak, no bark." Seasoned, dry hardwood. Bark introduces smoke, pitchy sap, and inconsistent heat. Soaked wood chips are OK for SMOKING — not for the primary fuel load.
Hands-on tips
- Peak flavor and heat retention come from the refractory after cure — HPC says the oven retains cooking heat for "a couple hours after being used." Your second meal of the day often comes out better than the first.
- The dome is self-cleaning: food drippings get re-burned when you pile hot embers on them for 10 minutes.
- If you only have one wood option, oak over mesquite — oak burns hotter and longer.
Questions people ask
Can I use the oven in freezing temperatures?
Yes — but gradually. Use gas-only to warm the oven, then add wood. Thermal shock on cold refractory is the enemy. HPC publishes a dedicated video for freezing-temp firing.
What if cracks form in the hearth stone later?
Cracks up to 1/16" are normal control joints — part of the ceramic cure. Cracks over 1/8" should trigger a call to HPC for repair instructions or servicing.
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