PRO-Tect: Pipe Freeze Protection Single-Zone Control with GFEP

At a minimum: a PRO-Tect Pipe Freeze Protection Self-Regulating Cable, an End Seal kit, and a Power Connection Kit. However, we also strongly recommend a control. All of these components are directly available from WarmlyYours (along with other accessories).

Use of another manufacturer’s components will void the warranty.

WarmlyYours offers four thermostat and controller options for PRO-Tect pipe freeze protection heating systems:

• Air Sensing Thermostat (AIR-STAT) — A simple automatic thermostat with a capillary bulb sensor. Activates when air temperature drops to 40°F and shuts off when it warms back up. Lowest-cost automatic option. Rated for 22A at 240V. NEMA 4X outdoor enclosure.
• Economy Pipe Thermostat (PT-ECONOMY) — Four fixed temperature setpoints (30°F, 38°F, 45°F, 50°F), built-in GFEP, LED status indicators, and a 20-foot sensor lead. Rated for 30A. Good for standard residential and light commercial installations.
• Single-Zone Digital Thermostat (PT-SINGLE) — Fully adjustable setpoint (-99.9°F to 999°F) with a 2.7" display, adjustable GFEP (1–300mA), and a 100k ohm NTC sensor with 20-foot lead. Rated for 30A. Best for precise temperature control.
• Dual-Zone Digital Thermostat (PT-DUAL) — Same digital control as the PT-SINGLE but manages two independent heating circuits from a single enclosure. Includes two sensors. Best for large installations or multi-zone pipe protection.

All controls include the sensor, feature NEMA 4X weatherproof enclosures, and are rated for non-hazardous locations. Contact our radiant experts for help selecting the right control for your project.

GFEP stands for Ground Fault Equipment Protection. It is a safety circuit that continuously monitors the current flowing through your heating cable. If a ground fault is detected (current leaking to ground, which can indicate damaged cable insulation), the GFEP trips the circuit and shuts the system off.

GFEP is important for pipe freeze protection systems because:

• Heating cables are often installed in damp or wet environments (under pipes, in crawl spaces) where insulation damage is more likely.
• A ground fault in a high-current heating circuit can cause fire, shock hazard, or cable failure.
• GFEP trips before the fault escalates, protecting your property and your heating system.

The PT-ECONOMY includes a fixed 30mA GFEP. The PT-SINGLE and PT-DUAL have adjustable GFEP (1–300mA) so you can set a sensitivity level appropriate for your installation. The AIR-STAT does not include GFEP.

If your installation is in a wet or damp location, WarmlyYours recommends choosing a control with built-in GFEP for maximum protection.

The correct temperature setpoint depends on which control you have and where the sensor is installed:

Air Sensing Thermostat (AIR-STAT) — Fixed setpoint of 40°F. The system activates when air temperature drops to this level and shuts off when it warms up. No adjustment needed.

Economy Thermostat (PT-ECONOMY) — Four preset options: 30°F, 38°F, 45°F, or 50°F. For most pipe freeze protection applications, 38°F or 40°F is a good starting point—it activates the cable before pipes reach freezing temperatures.

Digital Thermostats (PT-SINGLE / PT-DUAL) — Fully adjustable. A common recommendation is to set the activation point between 35°F and 40°F if measuring air temperature near the pipes, or slightly higher (45°F–50°F) if the sensor is measuring pipe surface temperature directly.

For specific guidance on setpoint and sensor placement for your installation, contact our radiant experts—we can help you set up the system correctly for your climate and pipe location.

You need the PT-DUAL dual-zone thermostat when your pipe freeze protection installation has two independent heating circuits that you want to control from a single enclosure.

Common scenarios that require dual-zone control:

• Two separate pipe runs in different areas (e.g. crawl space and exposed exterior plumbing)
• A large installation that was split across two circuits to stay within the 30A per-circuit load limit
• Two different pipe materials or exposure levels that benefit from independent temperature setpoints

The PT-DUAL includes two sensors and two independent sets of controls in one NEMA 4X enclosure. Each zone can have its own temperature setpoint and operates independently.

If you only have one heating circuit, the PT-SINGLE is sufficient. If you are unsure how many circuits your installation requires, our free system design service will tell you exactly what you need.