1″ GURU PC® Passenger Rail Car Freeze Protection


The 1″ thermostatic GURU PC® freeze protection valve is installed at the lowest point within the potable water-bearing systems on a passenger rail car to prevent the water from freezing when the car heat is turned off for switching locomotives or even brief layovers.

This self-contained freeze protection drain valve monitors ambient temperatures and will automatically drain the system if the air temperature falls to the valve’s set-point, 35°F (1.7°C), preventing burst piping and thousands of dollars in damage. Once the car heat is restored, the valve will modulate closed, allowing for the tank to be refilled before returning to service. Since the valve is completely mechanical, no electrical or air connections are required for the valve to operate.

To avoid a delay in refilling the water system and getting the passenger car back into service after a valve activation we recommend using our electric heater assembly. The heater attaches to the thermal actuator on the valve and will warm it up quickly once power is restored to the car. This allows the GURU PC® freeze protection valve to close and the potable water system to be refilled quicker after a drain occurrence.

NSF 61 Certified and shock and vibration tested, the GURU PC® is compact, reliable, and in-line serviceable for ease of maintenance.

GURU PC® Freeze Protection Valve

Design Features

  • Exclusive self-actuating Thermoloid® blend paraffin wax actuator
  • Low lead brass/bronze
  • Dual port seals
  • In-line serviceable


  • Self-operating – no external power source required
  • Eliminates costly freeze damage in a passenger car
  • High flow design for rapid draining
  • Easy installation
  • Minimal maintenance required
  • NSF 61/372 certified
  • Shock & Vibration tested

Heater Assembly Features

  • 2 LED lights for easy visual check of power and heater
  • Fully encapsulated PC board
  • Self-limiting heater
  • No moving parts to wear
  • Minimal electrical noise
  • Easy installation/removal with one hand
  • Heaters available: 120 VAC/74 VDC & 230 VAC

GURU PC® freeze protection valve with Heater Assembly


  • Size: 1” NPT
  • Maximum Operating Pressure: 120 PSIG (8.3 BAR)
  • Full Open Temperature: 35°F (1.7°C)
  • Closing Temperature: 45°F (7°C)
  • Operating/Storage Temperature Range: -67°F – 160°F (-55°C – 71°C)


1″ GURU PC Product Sheet
1″ GURU PC Installation and Maintenance Instructions
1″ GURU PC Rebuild Kit Installation and Maintenance Instructions
Railroad Brochure
GURU PC Case Study