Watts 0163754 Valve R-410A this is a single-stage thermostat

this is a single-stage thermostat only

Precision Control: Utilizes Auto-Tuning (PRAC+) and optimal start logic to maintain tight temperature tolerances and improve overall energy efficiency

The Danfoss 003L6025 (AVDO 20) is a self-acting automatic bypass valve designed to maintain a minimum flow rate and stabilize differential pressure in small-scale heating systems

including a plug on one side

Watts 0163754 Valve R-410A this is a single-stage thermostatThe Watts 0163754, also identified as the 40XL 7 100, is a heavy duty, automatic reseating temperature and pressure relief valve engineered for high capacity commercial water heating systems. Designed for precise protection, this 1 inch NPT valve manages thermal expansion and over pressure conditions with a 1,481,000 BTU hr steam discharge capacity. It features a durable bronze body and a 7 inch thermo bonded coated extension thermostat to ensure