Honeywell T775P2003 Electronic Temperature Controller – Boiler Special
Product Overview
The Honeywell T775P2003 is a next-generation electronic remote temperature controller designed for commercial and agricultural boiler applications. It provides precise temperature monitoring with switched and/or proportional outputs, enabling efficient control of various loads.
The controller comes equipped with three high-accuracy 50021579-001 sensors for monitoring return air, discharge air, and mixed air, replacing the older C7170B1000 sensors, making it ideal for sophisticated boiler control setups.
Important: The T775 is an operating control, not a limit or safety device. Applications requiring safety or limit control must include a separate safety or limit device.
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Fast-response, highly accurate sensors included
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Temperature range: –40°F to 248°F (–40°C to 120°C)
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Easy-to-use graphical interface with keypad lockout
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Internal time clock scheduler for energy savings and output control
✅ Key Features
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✔️ Electronic remote temperature control for boiler applications
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✔️ NEMA 4X rated for indoor use
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✔️ Proportional and switched outputs
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✔️ Includes 3 temperature sensors (50021579-001)
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✔️ Accurate to ±1°F at 77°F
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✔️ Throttling range: 1°F to 150°F
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✔️ Output reset and stages loop control
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✔️ Built-in scheduler for setback/disable options
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✔️ Easy-to-program graphical interface with keypad lockout
🔧 Specifications
| Specification | Details |
|---|
| Model |
T775P2003 |
| Brand |
Honeywell |
| Application |
Electronic Remote Temperature – Boiler Control |
| Output |
1 Digital, 4 SPDT |
| Sensor Inputs |
3 (50021579-001) |
| Voltage |
24V, 120V, 240V |
| Hertz |
50/60 Hz |
| Contact Ratings |
24V: 10 A resistive
120V: 58.8 ALR, 9.8 AFL, ½ HP, 125 VA Pilot
240V: 29.4 ALR, 4.9 AFL, ½ HP, 125 VA Pilot |
| Sensor Type |
1097 Ω PTC @ 77°F, Stainless Steel Probe |
| Max Distance to Sensor |
1000 ft |
| Bulb Size |
¼” x 2” |
| Temperature Range |
–40°F to 248°F |
| Accuracy |
±1°F at 77°F |
| Throttling Range |
1°F to 150°F |
| Ambient Operating Temp |
–40°F to 140°F @ 60Hz
–40°F to 125°F @ 50Hz |
| Dimensions |
H: 8.156", W: 4-13/32", D: 2-15/16" |
| Certifications |
NEMA 4X |
🔄 Sensor Cross Reference
| Old Part Number | New Part Number | Description | Brand |
|---|
| C7170B1000 |
50021579-001 |
Standard temperature sensor for T775 controllers |
Honeywell |
Note: The T775P2003 includes three 50021579-001 sensors for return air, discharge air, and mixed air monitoring, replacing the older C7170B1000 sensors.
⚠️ Common Symptoms of a Failing Controller
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Inaccurate temperature readings
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Boiler cycles erratically or fails to maintain setpoint
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Relay outputs do not activate
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Sensors malfunction or lose connectivity
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Scheduler functions not responding
❓ Frequently Asked Questions (FAQ)
Q: What sensors come with the T775P2003?
A: Three 50021579-001 sensors for return air, discharge air, and mixed air. These replace the older C7170B1000 sensors.
Q: Can the T775 be used as a safety limit control?
A: No. It is an operating control only. Separate safety or limit controls are required.
Q: What temperature range does it cover?
A: –40°F to 248°F (–40°C to 120°C).
Q: Does it have a programmable time scheduler?
A: Yes, with setback and disable output options for energy savings.
Q: How accurate is the T775P2003?
A: ±1°F at 77°F, with fast-response sensors.
🛒 Shopping Tips
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Confirm compatibility with your boiler system before ordering.
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Ensure sensor placement matches the application (return, discharge, mixed air).
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Program the built-in scheduler for optimal energy savings.
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Replace aging T775 controllers to maintain precise boiler temperature control.
