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Johnson Controls A19ZBA-1 Temperature Control THPU32HP7Y What does it mean ifThe Johnson Controls A19ZBA 1 Temperature Control is a heavy duty mechanical switch purpose built for water chiller temperature control and refrigeration applications. Designed for reliability in demanding commercial environments, this remote bulb temperature control utilizes a liquid filled sensing element to provide high accuracy "repeat" performance that remains unaffected by barometric pressure or cross ambient temperature fluctuations. This SPST