Secop GS26CLX Reciprocating Compressor: 26.3 cm3, Five Rating Standards, and Two Sales Codes

By the Qishanr technical desk. Reviewed 29 October 2026.

The GS26CLX is a Secop hermetic reciprocating compressor with a 26.30 cm3 displacement, built for a low back pressure refrigeration envelope on a 220-240 V single-phase supply. Two facts make it a poor candidate for a one-line specification. First, the same machine is printed with five different capacities between 703 W and 1538 W, and every one of those figures is correct, because each belongs to a different rating standard. Second, the type designation covers two sales codes that differ in refrigerant and in the approval set, so a purchase order written against the type designation alone can land on either one. This article works through both, using the manufacturer datasheet as the primary document.

Key facts at a glance

Every row above is printed on the datasheet or computed from two printed rows. Nothing in this article is inferred from the model string except where the text says so explicitly.

What do the code and the two sales codes mean?

Secop does not print a model-code nomenclature for this family, so the string has to be read from the sibling set rather than from a rule. Three builds share the same 26.3 cm3 frame and differ only in the middle letters: GS26CLX is the low back pressure build, GS26MLX is the medium back pressure build and GS26MFX is a further variant listed for a different refrigerant. Across those three the leading digits track displacement exactly and the middle letters track the envelope. That is a correlation observed in the catalogue, not a decoding rule, and it should not be extended to other families without checking.

The sales code is the part that matters commercially, because it is the part that fixes the refrigerant and the approvals:

The two codes are the same hardware and the same motor. What separates them is the gas they are charged with and the markets they are cleared for: the R404A build carries the EAC mark, the R452A build does not, and each build is rated on its own refrigerant. A buyer who specifies "GS26CLX" and stops there has specified a type, not a part number. The status of each code is printed on the Secop configuration page for this model, and the two data sheets carry the same motor, the same 220-240 V supply and the same 198-254 V range, so the choice between them is a refrigerant and approvals decision rather than a hardware one.

Why does the same compressor carry five capacities?

Because a capacity figure is meaningless without the standard it was measured to, and this datasheet prints five of them side by side. All five are at 220 V, 50 Hz, CSCR, with 3 m/s of forced air over the shell, and all five sit in the low back pressure band:

The highest and lowest entries describe the same compressor and differ by a factor of 2.19. The reason is visible in the first four columns: AHAM rates the machine against a 40.6 C condensing temperature, while ASHRAE rates it against 54.4 C and CECOMAF against 55 C. Lift, not hardware, is doing the work. The COP column follows the same pattern, from 0.95 under the CECOMAF condition to 1.65 under the AHAM one.

Three arithmetic checks confirm the table is internally consistent rather than assembled from different sources. ASHRAE closes as 1322 divided by 980, which gives 1.35, the printed COP. The same row closes in imperial units as 1322 times 3.412, which gives 4511 Btu/h, and in kilocalories as 1322 times 0.86, which gives 1137. The AHAM row closes the same way at 1538 divided by 931, which gives 1.65.

Which number should go into a quotation depends on the customer, and the honest answer is that the standard has to be named in the same sentence as the figure. A European tender will normally expect EN 12900, and that is the lowest of the five at 703 W. A North American specification will normally expect ARI540 or ASHRAE. Quoting the AHAM figure against an EN 12900 requirement overstates the machine by a factor of more than two, and no amount of datasheet citation will repair that once the equipment is on site.

What does the low back pressure envelope cover?

Low back pressure means the evaporating temperature sits well below zero and the compressor is expected to run there continuously, not only during a pull-down. The datasheet's performance tables give the shape of that envelope at two condensing temperatures:

Two things follow. The machine is usable down to 416 W of capacity at the coldest printed point, which is the region where frozen storage and low-temperature display equipment operate. And the cost of a ten-kelvin rise in condensing temperature is severe at the cold end: at -40 C the capacity falls from 416 W to 264 W, a loss of 37 percent, for the same compressor speed and the same evaporator.

The datasheet also prints the operating limits that sit around that table. Ambient temperature for the unit is 10 to 38 C, machine room temperature at the compressor is 10 to 43 C, and the figures above assume 3 m/s of air movement over the shell. Hot gas defrost is marked as acceptable, and so is long interval pull down, which is the pattern a frozen cabinet sees after a defrost cycle. What the datasheet does not do is claim the medium back pressure band: that role belongs to the MLX build, and a specification that needs to run at chilled temperatures should not be met by stretching this one. For the application side, the cold chain literature indexed by the International Institute of Refrigeration covers frozen retail and cold room practice at this temperature band, which is the context in which the coldest corner of the table is normally used.

What does CSCR with high starting torque require on site?

The motor is a capacitor-start capacitor-run machine with high starting torque, which is the configuration a single-phase compressor needs when it has to start against a pressure difference rather than from equalised pressures. The electrical data is specific enough to design a panel from:

The 26 A locked rotor figure against a 4.8 A running current is a ratio of about five to one, which is ordinary for a single-phase machine of this size but is not ordinary for the wiring that feeds it. A circuit sized on running current alone will trip on every start, and the start capacitor is not optional equipment to be added later if the panel is tight: with CSCR the capacitor is part of the approved configuration, and the datasheet lists the 20 uF run and 100 uF start values as the ones the ratings were established with. The starter kit referenced in the datasheet is a single part, which is the simplest way to buy the correct combination rather than assembling it.

Which refrigerant, R404A or R452A?

Both are listed for this compressor, and the difference is not cosmetic. On the ASHRAE low back pressure condition the R404A build gives 1322 W at a COP of 1.35, and the R452A build gives 1219 W at the same COP. That is 7.8 percent less capacity from the same displacement, the same speed and the same motor. Under EN 12900 the gap is 703 W against 638 W, or 9.2 percent. The evaporator and the expansion device therefore have to be sized for the refrigerant that will actually be charged, and a system designed on the R404A figures will run short if it is filled with R452A.

The two builds are not interchangeable in approval terms either. The R404A code carries VDE, CCC and EAC; the R452A code carries VDE and CCC. Where the EAC mark is a market requirement, the R404A build is the only one of the two that satisfies it, which is a purchasing constraint that has nothing to do with thermodynamics and everything to do with customs.

Both builds use POE oil at 32.5 cSt with a 902 ml charge, so the lubricant does not separate the two. The refrigerant charge technical limit is 2000 g, which is the ceiling the compressor is documented for, not a system design target. Regulatory treatment of these two gases is not identical, and the governing framework in the European Union is Regulation (EU) 2024/573, which attaches obligations to the equipment and its charge rather than to the compressor alone.

Where does it sit against its siblings?

The useful comparison is not with a different brand but with the builds that share the same frame. The figures below are taken from the supplier's own listings rather than from datasheets, so they are class labels and single-point capacities rather than standard-condition ratings, and they should not be compared with the five-standard table above:

The GS26MLX row is the one to read carefully. It shares the 26.3 cm3 displacement with the subject of this article and is listed at 2243 W against 1430 W, a difference of more than fifty percent on the same swept volume. That is not a better compressor; it is the medium back pressure build running at a warmer evaporating temperature, which is exactly the effect the five-standard table demonstrates from the other direction. Displacement tells you the size of the machine, never the duty it is rated for.

The GS26MFX row makes a second point. It is the same frame again, listed for R134a, which places it in a different refrigerant family altogether and makes it unsuitable as a substitute in an R404A circuit regardless of the mechanical fit. The GS34CLX technical page prints the same family data one frame size up, which is where the pattern of this table can be checked against a second displacement.

How should a buyer specify this model?

The Secop compressor selection page groups the family by envelope and by supply, which is the right starting point when the frame size has not yet been fixed. Once it has, the seven steps below are the ones that decide whether the right part number arrives.

Read against those steps, the case for this model rests on five printed facts rather than on adjectives. The envelope reaches -40 C evaporating, so frozen retail and cold room duty sit inside the documented range without stepping up a frame size or moving to a two-stage arrangement. Hot gas defrost and long interval pull down are both marked acceptable, which puts a cabinet that defrosts on a timer inside the application rather than outside it. High starting torque is part of the approved motor configuration, which is the property a single-phase circuit needs when it restarts against a standing pressure difference rather than from an equalised state. One frame carries two refrigerants under two sales codes, so a spares line built around this frame serves both an R404A fleet and an R452A retrofit, provided the capacity is re-sized rather than carried across. And the approval set on 107B0500 covers the European, Chinese and Eurasian markets together on one code, so three market requirements can be met without stocking a second build.

The mechanical package is compact for the duty. The shell is 259 mm high at its tallest point and 173 mm wide, the compressor weighs 20.00 kg, and it is supplied 48 to a pallet. The connectors are copper: a 12.75 to 13.05 mm suction stub, an 8.15 to 8.25 mm discharge stub and a 6.4 to 6.6 mm process stub, all straight tube ends rather than rotalock fittings, which means the joint is brazed and the pipework has to be planned accordingly. The mounting kit is an M8 bolt joint with a 19 mm bore, listed as a separate part number, and a 3D model is referenced on the datasheet for anyone laying out the base plate.

Which standards and approvals frame the purchase?

Three layers apply. The rating layer is the standard named in the quotation: EN 12900 in Europe, ASHRAE or ARI540 in North America, CECOMAF in parts of Europe, AHAM in the domestic appliance world. The international counterpart of that rating work is carried by the ISO committee responsible for testing and rating of refrigerant compressors, which is the body to consult when a specification has to be written across markets rather than within one. The refrigerant layer is Regulation (EU) 2024/573 for equipment placed on the European market, which regulates the gas and the charge rather than the compressor as a component.

The approval layer is specific to this model and differs between the two codes. VDE is the electrical safety approval and appears on both builds; the VDE Institute is the body behind that mark. CCC covers the Chinese market and EAC covers the Eurasian customs union, and only the R404A build carries both of them together. A tender that names EAC has, in effect, already chosen the refrigerant.

This article was checked in one pass against the manufacturer datasheet dated October 2026, page by page, with every capacity figure traced to its row and its stated condition. Two arithmetic checks are shown in the text and both close. The supplier's own product listing was read against the datasheet and the differences are stated where they occur rather than reconciled silently. For readers who want the wider context rather than this one model, the news and technical index on this site collects the technical notes behind the family.

Frequently asked questions

What is the cooling capacity of the GS26CLX?

There are five published answers. Under ASHRAE low back pressure conditions it is 1322 W; under CECOMAF 888 W; under EN 12900 703 W; under ARI540 998 W; under AHAM 1538 W. The figure is only meaningful with the standard attached.

Is it a low back pressure or a medium back pressure compressor?

Low back pressure. The datasheet application field reads LBP, and every one of the five rating rows publishes a value in the low back pressure column and nothing in the medium back pressure column. The medium back pressure role in the same frame is filled by the MLX build. For the supplier's own labelling of the band between the two, the medium-low back pressure page is the reference.

What is the difference between 107B0500 and 107B0526?

The refrigerant and the approvals. 107B0500 is the R404A build with VDE, CCC and EAC; 107B0526 is the R452A build with VDE and CCC. Capacity differs by roughly eight percent between them, and the R452A build carries no EAC mark.

Can it be converted from R404A to R452A in the field?

Only by changing the sales code, because the two are rated separately and their approval sets differ. The mechanical envelope is the same, but a system sized on the R404A figures loses about eight percent of its capacity when charged with R452A, and the expansion device has to be re-selected rather than adjusted.

Does it need a start capacitor?

Yes. The motor is CSCR with high starting torque, the approved configuration uses a 20 uF run capacitor and a 100 uF start capacitor, and the locked rotor current is 26 A against a rated load current of 4.8 A. A panel sized on running current alone will not start the machine.

What is the displacement and what does it imply?

26.30 cm3 per revolution at 2900 rpm, which is a swept volume of about 4.58 m3 per hour. That is the size of the machine, not its duty: the same swept volume is sold as a low back pressure build at 1322 W and as a medium back pressure build listed at 2243 W.

Is 1 HP correct?

One horsepower is a reseller class label and it does not appear on the datasheet, which publishes no horsepower field at all. The printed electrical data is 4.8 A rated load current and 220-240 V single phase. Size the machine from the capacity at your own design point and from the current, not from the class label.

Can it be used for freezing duty?

Yes, within the printed envelope. The performance tables run down to -40 C evaporating, where the capacity is 416 W at 45 C condensing and 264 W at 55 C condensing. A frozen application at that end of the range should be checked against the suction temperature limits in the operation diagram rather than against the headline capacity.

Sources