{"id":9056,"date":"2026-11-12T04:15:35","date_gmt":"2026-11-12T04:15:35","guid":{"rendered":"https:\/\/www.compressorpartsmall.com\/?post_type=product&p=9056"},"modified":"2026-11-12T05:54:23","modified_gmt":"2026-11-12T05:54:23","slug":"atlas-copco-1202586903-thermostatic-valve-65c","status":"publish","type":"product","link":"https:\/\/www.compressorpartsmall.com\/ru\/product\/atlas-copco-1202586903-thermostatic-valve-65c\/","title":{"rendered":"Atlas Copco 1202586903 Thermostatic Valve 65\u00b0C for Oil-Injected Screw Compressors"},"content":{"rendered":"

\u042d\u0442\u043e\u0442 1202586903<\/strong> is the Atlas Copco thermostatic valve for the oil circuit of oil-injected screw compressors, listed as VALVE THERM. 65\u00b0C. The valve is the temperature-sensitive junction of the oil system: it decides how much of the oil flow passes through the oil cooler and how much takes the bypass on the way back to the element. The official part page records it under the S4B Valve rate group, with Germany as country of origin and customs tariff code 8481900090.<\/p>\n

Oil-injected screw machines run a closed oil loop around the element, and the temperature of that loop decides how the machine behaves at part load and after a cold start. The 1202586903<\/strong> holds the control at one point in the loop, working mechanically from the temperature of the oil itself, with no controller signal and no electrical part involved.<\/p>\n

The application record for the valve is wide. It covers the stationary GA programme from the GA 75 VSD and GA 90 VSD through the GA 90 to GA 160 band and up to the GA 315 to GA 500 machines, and it reaches into the portable programme as well, from the diesel-driven XAS, XATS, XAMS, XAHS and XAVS units to the electric E-AIR T900. The parts system also records 1830080589<\/strong> as the new version of the 1202586903<\/strong>, and both numbers are carried in the specification table below.<\/p>\n

What the Thermostatic Valve Controls in the Oil Circuit<\/h2>\n

In an oil-injected screw compressor the oil leaves the separator, passes through the oil cooler, and returns to the element, where it lubricates the bearings, seals the compression gap and carries away the heat of compression. The loop is sized for the running temperature of the machine, but the oil does not start there: a machine that has been standing overnight holds oil at ambient temperature, and a machine running at part load makes less heat than one running fully loaded.<\/p>\n

\u042d\u0442\u043e\u0442 1202586903<\/strong> is installed at the branch where the oil path splits between the cooler and the bypass line. While the oil is below its operating temperature, the valve keeps the flow on the bypass so the oil warms quickly in circulation. As the oil passes the rating of the valve, the element inside it shifts the flow progressively into the cooler branch, and the loop settles into its regulated temperature band.<\/p>\n

The whole action is mechanical. Inside the 1202586903<\/strong>, a temperature-sensitive element reacts to the oil flowing past it and moves the internal path accordingly, so the regulation follows the machine wherever it is installed and whatever controller runs it.<\/p>\n

\"Atlas
Atlas Copco VALVE THERM 1202586903 (1)<\/figcaption><\/figure>\n

The 65\u00b0C Rating and Cold-Start Protection<\/h2>\n

The 65\u00b0C in the designation of the 1202586903<\/strong> is the temperature rating of the valve, the point at which its element begins to direct oil into the cooler branch. Below that point the bypass carries the flow, and above it the cooler share grows until the loop balances against the heat the machine produces.<\/p>\n

The rating matters because oil temperature and oil condition are linked. Oil that stays below its operating temperature holds the moisture that condenses inside a compressor circuit, and that moisture travels with the oil into the bearings, the separator and the cooler. A valve that keeps the bypass path closed off until the oil is warm gives the machine a fast, clean passage from cold start to regulated running, and it is the reason oil-injected screw packages carry a thermostatic valve such as the 1202586903<\/strong> as standard equipment.<\/p>\n

For a machine that runs short duty cycles or stands in an unheated plant, the passage through that rating is where the valve does most of its work. The 1202586903<\/strong> repeats the transition every start-up, which is why its condition belongs on the service list beside the filters and the separator.<\/p>\n

\"Atlas
Atlas Copco VALVE THERM 1202586903 (2)<\/figcaption><\/figure>\n

Confirmed Applications Across the GA and Portable Range<\/h2>\n

The application record for the 1202586903<\/strong> stretches across two sides of the Atlas Copco catalogue. The confirmed machines include:<\/p>\n