Prusa Pro HT90: engineering materials and installation requirements

Two heads in the box, two different jobs

According to Prusa's product page, the HT90 ships with two direct-drive print heads, both included in the basic package. The High-Flow head carries a quick-swap 0.4 mm Revo nozzle. Prusa positions it for rapid prototyping with materials up to 300 °C. The Prusa Knowledge Base adds that this is the default head on the printer and that it targets a high volumetric rate for faster printing.

The High-Temp head carries an abrasion-resistant 0.6 mm Revo nozzle and reaches 500 °C. Prusa pairs it with materials such as PEEK, PEKK or PEI (Ultem). Prusa describes the swap as simple: the head is held by magnets, you detach it from the arms, unplug the cable at the top of the printer, and fit the other head. Our sources do not say whether a tool is needed for this step.

On nozzles, the spec sheet says all Revo nozzles are hardware compatible, but some are not supported and may require a custom slicer profile. The stated maximum filament flow is 40 mm³/s, a figure Prusa gives for ABS with a 0.8 mm nozzle, without an equivalent figure for the supplied 0.4 and 0.6 mm nozzles. For background on how diameter and flow interact, see the guide to 3D printer nozzles.

Heated chamber, bed and filtration: what the machine supplies

Prusa's page lists an actively heated chamber up to 90 °C, a bed up to 155 °C, and a nozzle temperature of 300 °C or 500 °C depending on the head. Prusa presents the hot chamber as the way to limit warping and layer delamination on large ABS or ASA parts. That is a manufacturer statement rather than an independent measurement, and the outcome also depends on your profile and geometry.

The machine uses delta kinematics: three lightweight arms move the head while the part stays still. Prusa draws a precision and speed argument from this, citing Klipper firmware, Input Shaper and Pressure Advance in the spec table. Cooling comes from a side-mounted turbine and a servo-operated flap that redirects airflow to specific areas of the model, which Prusa presents as a benefit for overhangs without overcooling the rest of the part.

The chamber includes a closed recirculation loop with a HEPA and carbon filter. Prusa also describes an automatic intake flap that manages temperature for PLA and PETG so they can be printed with the chamber closed. To put these features in context against ordinary enclosures, read the page on 3D printer enclosures.

Which materials go on which head, per Prusa

The spec table separates the two lists. For the High-Flow head, Prusa lists PLA, ASA, PETG, Flex (TPU, TPE), ABS, PA, PC, PCCF, PP and more. For the High-Temp head, Prusa lists PEI (Ultem), PEEK, PEKK, PPSU, PSU, PPS, PES and more. The HT90 Knowledge Base hub offers dedicated articles per material: PEI, PPS, PEEK-CF, PPSU, PSU and PEKK-CF.

These lists are manufacturer statements. They do not guarantee that a specific commercial PEEK or PPS spool prints without tuning. Before buying, check the filament maker's data sheet and the matching Prusa article. Prusa mentions aerospace and medical use cases; those describe industries, not a certification of your own parts.

For High-Flow materials, this site already has useful material pages. The pages on nylon and polycarbonate cover the moisture and temperature constraints of those materials. According to Prusa, the 90 °C chamber targets warping and layer delamination; moisture is a matter of filament drying, which Prusa stresses for high-performance polymers and which is covered further down.

What your shop has to provide

The spec table gives the footprint: 530 mm wide without the filament holder, 530 mm deep, 1050 mm tall, and 1470 mm with the door open. The door slides vertically, which explains the gap. Plan for a floor spot or a low bench with real vertical clearance, not a desk shelf.

For power, Prusa lists 110 V 15 A or 230 V 10 A, 50/60 Hz. Confirm that the available circuit handles that rating, especially if a drying oven or other machines share the same line. For environment, the spec table lists an operating temperature range of 20 to 32 °C and a maximum humidity of 85 % non-condensing. Measure those conditions at the planned location, especially in a garage or a room with variable temperatures.

Connectivity includes an RJ45 Ethernet port and a detachable Wi-Fi module. Prusa emphasizes fully offline operation, with the option to physically remove the module, a local mode limited to your network, or Prusa Connect for remote access. A built-in camera and chamber lighting are included, and an external USB camera can be attached. Initial setup runs through a 7-inch touchscreen with automatic calibration, and three Loadcell sensors handle first-layer distance according to Prusa.

The ecosystem that comes with the machine

The product page we consulted shows no price: it points to a price quote request to the sales team. The real budget therefore goes beyond the printer, and several items are described on the product page itself. The first is drying. Prusa states that many high-end materials are hygroscopic and that without a dry box, printing certain materials is practically impossible, especially PEI, PEEK, PEKK or PSU.

Two accessories are offered. The Prusa Pro Filament Drybox, a hermetically sealed box for storing and printing moisture-sensitive filaments. And the Memmert UF30 dryer, a stainless-steel lab oven that Prusa lists with a 20 to 300 °C range and a 32-liter chamber, meant to dry filament before it goes into the drybox. An HT90 maintenance kit bundles tools, replacement parts and cleaning supplies.

Print surfaces also belong in the budget. The package includes a textured powder-coated sheet; satin, PA, PP and high-temperature sheets are listed as optional. To understand why active drying matters, see the page on filament dryers. To lay out the full budget, the startup budget tool helps you list these items without forgetting consumables.

Who it is for, and how it sits among other Prusa machines

The HT90 offers a nozzle up to 500 °C and a chamber up to 90 °C for the high-performance polymers Prusa lists, with stated offline operation. These are machine maxima, not required temperatures for every grade. If your parts stay in PLA, PETG, ABS or nylon, first check whether a less specialized Prusa machine covers your materials; our HT90 sources do not document the other models, so consult the Prusa Core One and Prusa XL pages to compare enclosure, kinematics and power requirements.

The Ø300 × 400 mm cylindrical volume also takes some adjustment. A long flat part that fits a rectangular bed does not necessarily fit inside a 300 mm circle. On the other hand, the 400 mm height suits tall parts. Prusa notes that high-performance materials target small to medium-sized objects, not the whole volume.

Before requesting a quote, list your actual materials, check each filament data sheet, confirm floor space and door-open height, and plan for drying. The guide to professional 3D printers presents other options for professional use, and Prusa's product page describes the PrusaSlicer, Prusament and Printables ecosystem that comes with the machine; our Prusa brand page rounds out the picture.

Sources and limits

• Prusa Pro HT90 — manufacturer specifications
• Prusa Pro HT90 — Knowledge Base

We organize manufacturer and community documentation; we have not measured these products ourselves. The manual for your exact model takes precedence over general guidance.