What do the abbreviations H, HD, and HS mean for Pyrotec kilns?

If you click through the Pyrotec kiln range you quickly come across the abbreviations H, HD and HS – and wonder what is behind them. The answer is actually quite simple once you know the key. 

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Abbreviation H = 230 volts, regular outlet

The “H” stands for the PtRh-Pt type thermocouple (platinum-rhodium/platinum) in combination with a 230V connection. In short: a kiln with “H” runs on your regular Schuko outlet at home – no electrician, no three-phase power connection needed. That makes these models especially attractive for beginners and hobby potters.

A typical example is the Pyrotec Profitherm PY 75 H: 77 liter firing chamber, up to 1,200 °C, runs on 230V. Or the Pyrotec Kiln Studio ST 52 H with 52 liters and up to 1,200 °C – also Schuko-compatible.

The H in the name of the Pyrotec Profitherm PY 75 H indicates that no three-phase power is needed to run it

Abbreviation HD = 400 volts, three-phase power

“HD” stands for the same high-quality temperature sensor (PtRh-Pt), but with a 400V three-phase connection (CEE). That means more power, higher possible temperatures and larger firing chambers – but you need a three-phase power connection. A typical example is the Studio ST 68 HD: same size as the Studio ST 68 H, but with 5.7 kW instead of 3.6 kW and up to 1,260 °C. The higher power input from three-phase power allows either more volume or higher temperatures than the corresponding H model.

The HD in the name of the Studio ST 68 HD indicates that a three-phase power connection is needed to run it

Abbreviation HS = 400 volts plus swing lid

“HS” builds on “HD” – so also three-phase power and a PtRh-Pt thermocouple – and adds a decisive ergonomic advantage: the gas spring-assisted swing lid. Anyone who has ever lifted a heavy top-loader lid without support will understand immediately why that matters. The lid swings open, holds its position and at the same time protects the kiln wall with a sturdy rail. A classic example is the Pyrotec Profitherm PY 138 HS: 138 liters, 1,320 °C, three-phase power – and that very comfortable swing lid, which makes intensive work much more pleasant.

The HS in the name of the Pyrotec Profitherm PY 138 HS indicates that a three-phase power connection is needed to run it and that the kiln has a gas spring-assisted swing lid

The three Pyrotec series explained briefly

Besides the letter abbreviations, Pyrotec has two basic product lines you can choose between.

The Studio series (abbreviation ST) is designed primarily for earthenware and low-fire work – Pyrotec itself recommends it mainly for glaze firings up to about 1,150 °C. The insulation is sized accordingly, which keeps the price attractive. Technically, though, depending on the version the models reach up to 1,200 °C (H models) or even 1,260 °C (HD models). If you mainly work with earthenware clays, you are well and affordably set up here – if you regularly want to go to the upper temperature limit, you should consider the Profitherm series.

The Profitherm series (abbreviation PY) is the sturdier line, designed for higher temperatures. Depending on the version, Profitherm models reach up to 1,320 °C and are designed for more intensive use and high-fire work. If you want to fire stoneware or porcelain, or simply want to stay flexible in the long run, this is the one to go for.

The Profitherm HS series is the premium variant within the Profitherm line – technically built identically, but with the added gas spring-assisted swing lid, which makes opening and closing the lid much easier. If you fire regularly and intensively, you will quickly come to appreciate this comfort. The HS models all run on 400V three-phase power and reach up to 1,320 °C – they are the first choice for anyone who doesn't want to give up top firing performance and ergonomic working at the same time.

In short

 

If you are not sure which model fits your situation, just write to us. We at Formwerk Töpferbedarf Berlin are happy to help you find the right kiln for your power supply, your volume and your types of clay.