A Bitzer listing, from the manufacturer's published data.

Units: SI · US customary

Published specification

Model	BITZER GSD80235VA (R410A scroll, EN 12900)
Refrigerant	R410A
Performance data	AHRI 540 / EN 12900 10-coefficient map
Reference superheat / subcool	10.0 / 0.0 K
Cooling capacity @ 7.2/54.4 °C	51.68 kW
Input power @ 7.2/54.4 °C	19.36 kW
COP @ 7.2/54.4 °C	2.67

The map across its envelope

AHRI 540 / EN 12900 ten-coefficient polynomials in evaporating and condensing temperature, rated at 10.0 K superheat and 0.0 K subcooling; the solver corrects them to the operating superheat and subcooling. Envelope: the manufacturer's 5-sided polygon.

The rating point and three conditions across the published envelope. The whole map — every condition, the envelope and the curves — is in the builder: open this machine in the app. It solves any point inside the envelope, and warns past it.

Open this compressor in the app — the compressor-map tab, with its rating at any condition, its envelope, capacity and power lines and curves plotted, and the refrigerant's pressure–temperature chart a click away; or open the builder and pick it from the catalog picker — the solver runs it with the catalog's own figures, at your design point or across a year of weather.

All 14 Bitzer GSD models

How the model reads against this maker's data

BITZER ECOLINE recip and ORBIT/GSD scroll maps, the maker's own EN 12900 coefficients

9 maps — three ECOLINE semi-hermetic recips (4FDC-5, 4CDC-9, 4NDC-20) and six ORBIT/GSD scrolls (GSD60120/60182/80235/80295/80385/80485VA)

every map reproduces its recorded reading at 5 / 50 °C exactly (13.1 / 23.9 / 51.9 kW on the recips, 26.7 to 104.3 kW on the scrolls; COP 2.73 to 3.32), because nothing between the record and the seed touches a coefficient. Inside the envelope each map now carries, capacity and power stay positive, capacity rises with evaporating temperature and falls with condensing at every one of 169 grid points, and the COP stays under 80 % of Carnot. The maker states two ranges, which is a box, and on eight maps the cubic behaves everywhere in it; the GSD80235VA goes negative in the cold-and-hot corner (−9.3 kW at −23.8 / 65 °C, where its siblings read +8.0 and +13.7), so that corner is cut at the map's own zero-capacity contour and the cut is recorded. Not validated: no BITZER selection was reproduced end to end — the maps are the maker's coefficients, not a duty this project computed against the maker's software

From the validation page; every row is held by a test.

Listed from published data; a listing's figures are the manufacturer's, the model that runs them is ours. Solver results never depend on who has claimed what.