PECO thermostats provide precise, energy‑saving control for commercial spaces. The T170 model is a heating‑only thermostat that uses UP/DOWN arrows to set temperatures and offers continuous or demand‑based fan cycling. Settings persist through power outages. It supports advanced config via key combos!
Model T170 Features
The PECO T170 is a commercial thermostat designed for heating‑only applications. It features a simple, intuitive keypad with UP and DOWN arrows that allow users to fine‑tune the set point with a single click. The display shows the current temperature, set point, and fan status. In ON mode the fan runs continuously, while in AUTO mode the fan cycles on and off in response to heating demand. The thermostat supports three fan speeds—HI, MEDIUM, and LO—selected manually via dedicated buttons. It retains user settings even after a power outage, thanks to built‑in non‑volatile memory. The T170 can be configured for line or low‑voltage wiring, and it includes a keypad lock‑out feature for secure installations. Advanced configuration is accessed by holding the lower left and lower right keys simultaneously for about five seconds before mounting the unit, which opens a service menu for firmware updates and diagnostic checks. The unit is compatible with the PECO Wave wireless system, allowing remote monitoring and control through a TW205 receiver; Overall, the T170 delivers reliable, energy‑efficient heating control with straightforward programming and robust memory features. The T170’s user interface is designed for quick adjustments. The display updates in real time, and the keypad lock‑out prevents accidental changes during maintenance. The thermostat’s firmware supports future updates via the PECO Wave receiver, ensuring compatibility with newer building automation protocols and safety complianc and updates now
PECO thermostats provide precise, energy‑saving control for commercial spaces. The T170 model is a heating‑only thermostat that uses UP and DOWN arrows to set temperatures and offers continuous or demand‑based fan cycling. Settings persist through power outages. It supports advanced config via key combos!
The PECO T170 is a commercial thermostat designed for heating‑only applications. It features a simple, intuitive keypad with UP and DOWN arrows that allow users to fine‑tune the set point with a single click. The display shows the current temperature, set point, and fan status. In ON mode the fan runs continuously, while in AUTO mode the fan cycles on and off in response to heating demand. The thermostat supports three fan speeds—HI, MEDIUM, and LO—selected manually via dedicated buttons. It retains user settings even after a power outage, thanks to built‑in non‑volatile memory. The T170 can be configured for line or low‑voltage wiring, and it includes a keypad lock‑out feature for secure installations. Advanced configuration is accessed by holding the lower left and lower right keys simultaneously for about five seconds before mounting the unit, which opens a service menu for firmware updates and diagnostic checks. The unit is compatible with the PECO Wave wireless system, allowing remote monitoring and control through a TW205 receiver. Overall, the T170 delivers reliable, energy‑efficient heating control with quick adjustments and robust memory features.
Installation Overview
The T170 installation is straightforward: confirm transformer voltage, then connect R, Y, and G wires to the thermostat terminals per the wiring diagram. Mount the unit on a level wall plate and secure it. When the thermostat displays “Ready,” set a higher temperature; the furnace should cycle. The thermostat’s LED flashes during normal operation and stays steady red if a fault occurs. Proper installation guarantees reliable operation and maximizes energy savings PECO standards All
User Interface Basics
PECO T170’s interface is designed for quick, intuitive control. The front panel displays the current room temperature, the set point, and the fan status. The keypad consists of UP and DOWN arrows for adjusting the set point, a button for toggling between heating modes, and three dedicated fan speed buttons labeled HI, MEDIUM, and LO. The display also shows a small icon that indicates whether the fan is running continuously (ON) or cycling on demand (AUTO). To change the set point, simply press the UP arrow to raise the temperature or the DOWN arrow to lower it; each press moves the set point by one degree. The heating mode button cycles through OFF, ON, and AUTO, allowing the user to choose whether the furnace operates automatically or remains on continuously. The fan speed buttons are independent of the heating mode; pressing HI forces the fan to run at maximum speed, MEDIUM sets it to a moderate speed, and LO reduces it to the lowest speed. A lock‑out switch on the back of the thermostat disables the keypad, preventing accidental changes; this is useful in high‑traffic areas. For advanced users, holding the lower left and lower right keys simultaneously for about five seconds before mounting the unit unlocks a hidden service menu, where firmware updates and diagnostic functions can be accessed. The interface is fully operable via the keypad alone, with no need for external devices, making it ideal for quick adjustments on the fly; The thermostat also features a backlit display that illuminates in low light, ensuring visibility at night. Users can enable or disable the display backlight through the settings menu, which conserves battery life on low‑voltage models. The keypad is designed with tactile feedback, so each button click provides a satisfying click sound, confirming the input. Additionally, the thermostat offers a silent mode that suppresses audible alerts, useful in quiet office environments. Firmware updates are wireless now Yes.
Fan Operation Modes
The PECO T170 thermostat offers two primary fan operation modes to suit varying HVAC needs. In ON mode the fan runs continuously whenever the furnace is active, providing constant airflow and a steady temperature throughout the space. In AUTO mode the fan cycles on and off in response to heating demand; it activates only when the furnace is delivering heat, then shuts off once the set point is reached, conserving energy and reducing fan wear. Each mode can be selected by pressing the dedicated fan mode button on the front panel, which displays an icon that indicates the current state. The thermostat’s firmware automatically remembers the last chosen mode even after a power outage, thanks to its built‑in non‑volatile memory. Users can also fine‑tune airflow by selecting one of three fan speeds—HI, MEDIUM, or LO—using the corresponding buttons. HI delivers maximum airflow for rapid temperature changes, MEDIUM balances comfort with efficiency, and LO provides gentle circulation for quieter operation. The combination of mode and speed settings allows building managers to optimize comfort, energy use, and equipment longevity. For troubleshooting, if the fan fails to respond to mode changes, check the wiring connections and verify that the furnace fan relay is functioning. The T170’s fan control logic is designed to work seamlessly with both line‑voltage and low‑voltage HVAC systems, ensuring reliable operation in diverse commercial installations.
The thermostat’s fan control logic supports LEDs indicating fan status and error codes, allowing maintenance staff to identify issues. Additionally, the T170’s firmware can be updated wirelessly via the PECO Wave system, ensuring fan operation modes remain current with energy‑saving features.
Wireless System (PECO Wave)
PECO Wave is a wireless control platform that links the T170 thermostat to a central receiver, enabling remote monitoring and programming through a handheld or mobile app. The 2.4 GHz radio link supports up to 30 devices in a single network, providing robust coverage in large commercial buildings. Installation involves mounting the TW205 receiver on a grounded electrical box, connecting the 120 V power feed, and wiring the thermostat’s low‑voltage terminals to the receiver’s input. The receiver’s LED indicators confirm power status, signal strength, and error conditions. Once powered, the thermostat automatically discovers the receiver and establishes a secure link, displaying a “Connected” icon on the front panel. Users can access advanced settings via the app, such as scheduling, temperature history, and energy‑usage reports. The app also supports push notifications for fault alerts, allowing maintenance teams to respond quickly to issues like fan failures or low battery warnings. Wireless updates can be pushed to the thermostat firmware, ensuring the device remains compliant with the latest energy‑efficiency standards. For security, the system employs AES‑128 encryption, and each device is assigned a unique identifier that prevents unauthorized access. The Wave platform integrates with building automation systems via BACnet/IP, enabling centralized control of multiple thermostats and HVAC units. Maintenance personnel can perform diagnostics remotely, reducing on‑site visits and improving system uptime. The wireless range is typically 120 ft indoors, but can be extended with repeaters if needed. Overall, PECO Wave delivers a flexible, scalable solution that enhances comfort, reduces energy consumption, and simplifies building management. Its modular design supports future upgrades.
Programming Capabilities
The PECO T170 offers a versatile programming interface that allows users to tailor heating schedules, temperature setpoints, and fan behavior to match building occupancy patterns. By selecting the “PROGRAM” button, the thermostat enters a menu that displays the current day and time slots. Users can assign a setpoint for each slot using the UP/DOWN arrows, and the system will automatically adjust the heating coil to maintain the desired temperature. The thermostat supports up to 14 programmable periods per day, enabling fine‑grained control for peak and off‑peak hours. In addition to standard setpoints, the T170 allows a “comfort” temperature that overrides the schedule when the building is occupied; this feature is accessed via the “COMFORT” toggle. Fan operation can be set to ON, AUTO, or OFF. In AUTO mode, the fan cycles on and off with the heating demand, while ON keeps the fan running continuously. The thermostat’s internal clock and can be set and via the “CLOCK” option, allowing synchronization and with building schedules. Advanced configuration is accessed by simultaneously pressing the lower left and lower right keys for about five seconds; this brings up the service menu where technicians can view diagnostic logs, reset the system, or update firmware. All programmed settings are stored in non‑volatile memory, ensuring retention after a power outage. It also supports. The T170’s programming logic is intuitive, making it suitable for small offices and large commercial facilities that require precise temperature management.
Service Menu Access
To access the service menu on a PECO thermostat, first ensure the unit is powered and the display is active. Press and hold the lower left and lower right keys simultaneously for approximately five seconds. The screen will flash, indicating entry into the hidden menu. Once inside, use the UP/DOWN arrows to navigate through options such as firmware version, diagnostic logs, and calibration settings. The LEFT/RIGHT arrows allow selection of submenus. Press the SELECT button to confirm choices or to return to the main screen. The service menu provides technicians with the ability to reset the thermostat, clear error codes, and perform advanced configuration tasks that are not available in the standard user interface. It is recommended that only trained personnel use this menu, as incorrect changes can affect system performance. After completing tasks, press the EXIT button to return to normal operation. The thermostat will retain any changes made, and the menu will not be accessible again until the key combination is repeated. This secure method ensures that routine maintenance can be performed without exposing sensitive settings to end users.
Additional service functions include viewing the system clock, adjusting the time zone, and resetting the thermostat to factory defaults. Technicians can also update the firmware via the service menu, ensuring the unit runs the latest software. The menu displays diagnostic codes that help identify hardware faults. For safety, the thermostat logs all changes, allowing audit trails. Users should avoid modifying advanced settings unless instructed by support. All changes are saved automatically. See log!.
Power Management
The PECO thermostat is designed to operate reliably on low‑voltage wiring, typically 24 VAC, and includes built‑in protection against power interruptions. When the main power supply drops, the thermostat’s internal battery backup keeps the display and memory active for a short period, allowing the user to see the last setpoint and any error messages. After the battery depletes, the unit will automatically revert to a safe state, turning off the fan and heating elements until power is restored. The thermostat also features a power‑failure memory that records the most recent user settings, so that when electricity returns, the system resumes operation from the last known configuration without requiring a full reset. This memory function is critical for commercial buildings where frequent power outages can disrupt heating schedules. Users can manually trigger a power‑cycle test by briefly disconnecting the 24 VAC line; the display will flash “POWER OFF” and then “POWER ON” once the line is re‑connected, confirming the backup logic is functioning. For installations that require redundancy, PECO recommends connecting a secondary 24 VAC source in parallel, ensuring continuous operation even if one supply fails. The thermostat’s firmware logs power events, which can be accessed via the service menu for troubleshooting. Proper grounding of the low‑voltage wiring is essential; a loose ground can cause the unit to reset unexpectedly. Finally, the thermostat’s low‑voltage input is protected by a fuse rated for the expected current, preventing damage from surges. By following these guidelines, building operators can maintain consistent heating performance and reduce downtime. Additionally, the thermostat supports a low‑power mode that reduces the display backlight and sensor polling frequency when the building is unoccupied, further extending battery life during outages. The power‑management settings can be reviewed in the service menu, where technicians can view the battery status, voltage levels, and reset the memory if needed. Regular maintenance checks of the low‑voltage connections and the fuse ensure that the thermostat remains operational during extended power disruptions. By integrating these power‑management features, PECO thermostats provide reliable, energy‑efficient control for commercial HVAC systems, even under challenging electrical conditions.
Troubleshooting Guide
Check power, wiring, and fuse. Verify the display shows the setpoint. If fan stays OFF, confirm fan wiring and relay. For memory loss, reset by holding lower left/right keys. Contact support if errors persist. If the displayremains blank, check the transformer and reset
Temperature Adjustment Using UP/DOWN Arrows
The PECO T170 thermostat allows users to fine‑tune the desired temperature by pressing the UP and DOWN arrow keys on the front panel. Each press increments or decrements the set point by 0.5 °F (or 0.5 °C for Celsius mode). The display updates instantly, showing the new target value in the upper right corner.
To avoid accidental changes, the thermostat requires a brief pause after each arrow press. If the arrow is held down, the system will continue to adjust the set point automatically, stepping through the increments at a steady rate. This feature is useful for quickly raising or lowering the temperature during peak demand periods.
When the thermostat is in “ON” mode, the fan runs continuously, and the temperature adjustment directly influences the heating cycle. In “AUTO” mode, the fan will cycle on and off in response to the set point, providing a more efficient operation. Users can also lock the keypad to prevent unintended adjustments, which is especially useful in high‑traffic commercial environments.
For troubleshooting, if the UP/DOWN arrows do not respond, check the transformer voltage and ensure the thermostat is receiving 24 V AC. A lack of power will cause the display to remain blank and the arrow keys to be inactive. If the display shows a temperature but the arrows fail to change it, the internal firmware may need a reset by holding the lower left and lower right keys for five seconds. Settings stay!!
Fan Speed Selection: HI, MEDIUM, LO
The PECO T170 thermostat offers three discrete fan speed settings—HI, MEDIUM, and LO—to balance airflow, comfort, and energy efficiency. Press the “HI” button to engage the highest fan speed, which delivers maximum airflow for rapid temperature stabilization during peak heating demand. The “MEDIUM” setting provides a balanced airflow that reduces noise while still maintaining efficient heat distribution. Selecting “LO” limits the fan to its lowest speed, ideal for quiet operation or when the heating load is modest. These speeds are calibrated to match the HVAC system’s airflow specifications, ensuring that the blower motor operates within its rated capacity.
Fan speed selection is independent of the thermostat’s heating mode. In “ON” mode, the fan runs continuously at the chosen speed, ensuring constant airflow regardless of temperature changes. In “AUTO” mode, the fan cycles on and off in response to the heating cycle; however, the selected speed determines the airflow rate during each on‑cycle. When the fan speed is set to HI, the blower may consume up to 30% more power compared to LO, which can be significant in large commercial buildings. This allows users to tailor the system’s performance to specific building requirements.
To change the fan speed, simply press the corresponding button on the front panel. The display will show the current fan speed next to the temperature set point. If the fan speed does not change, verify that the thermostat is correctly wired to the HVAC system and that the transformer is supplying the proper voltage. A malfunctioning fan motor or a broken relay may also prevent speed changes; in that case, a service technician should inspect the HVAC equipment. If the fan speed is unresponsive, check the relay contactor and ensure the thermostat’s wiring harness is intact.
For advanced users, the service menu (accessed by holding the lower left and lower right keys for five seconds) offers additional fan control options, such as fan speed calibration and delay settings. These options are typically reserved for professional installers and should be used only after consulting the PECO T170 application guide. The service menu also allows setting a fan run delay, which can postpone fan activation until the heating coil reaches a certain temperature, further optimizing energy use and occupant comfort;
Advanced Configuration (Pressing lower left/right keys)
To access the service menu on a PECO thermostat, simultaneously press the lower left and lower right keys for approximately five seconds. The display will flash, indicating that the thermostat has entered configuration mode. Once in this mode, you can adjust parameters such as fan speed calibration, temperature offset, and system delay settings. These options are intended for qualified installers and should be used only after consulting the official application guide.
During configuration, the thermostat may display a series of icons or numbers that represent the current setting. Use the UP and DOWN arrows to navigate through the menu items. Press the SELECT button to confirm that the new setting is applied. If the thermostat returns to normal operation before five seconds have elapsed, reset it by removing the transformer power for 30 seconds and restoring power.
It is essential to document any changes made in the service menu, as they can affect system performance and warranty status. After completing configuration, test the thermostat by cycling through heating modes and verifying that the new settings are applied; If the thermostat fails to respond or displays an error code, reset it by removing the transformer power for 30 seconds and restoring power. Remember to back up thermostat settings before changes to avoid data loss and errors!
Low-Voltage Wiring and Power Failure Memory
PECO thermostats operate on a low‑voltage supply, typically 24 V AC from a transformer or a 120 V AC source with a built‑in step‑down module. Wiring must follow the manufacturer’s diagram: the transformer’s hot and neutral are connected to the thermostat’s power terminals, while the low‑voltage output feeds the thermostat’s control board. Incorrect polarity or a short can trigger the built‑in safety interlock, shutting the unit down to protect the circuitry.
When the transformer is removed or the line voltage drops, the thermostat’s internal battery backup keeps the display and memory active for a short period. During this time the thermostat records the last set point and mode, and the system will automatically restore those settings once power is restored. This “power failure memory” feature prevents loss of user configuration and ensures that the heating cycle resumes without manual re‑programming.
To verify low‑voltage operation, use a multimeter to measure the voltage at the thermostat’s power terminals. A reading of 20–25 V AC indicates proper transformer output. If the voltage is below 18 V AC, check the transformer rating, wiring continuity, and any inline fuses. For 120 V models, confirm that the step‑down module is correctly installed and that the input terminals are connected to the mains supply.
Refer to the PECO application guide or online support portal for wiring diagrams and safety precautions. Proper installation ensures reliable compliance!
Common Display or Button Malfunctions
PECO thermostats occasionally exhibit display or button issues that can disrupt normal operation. The most frequent problems include a blank or flickering LCD, unresponsive arrow keys, or a stuck “ON/OFF” switch. These symptoms often stem from a low‑voltage supply, a loose internal connection, or a software glitch.
When the screen goes blank, first check the transformer output. A voltage drop below 18 V AC can cause the display to lose power; If the voltage is adequate, inspect the thermostat’s internal board for corrosion or a loose ribbon cable. A simple reseating of the display connector often restores visibility.
Unresponsive buttons typically result from a worn key switch or a shorted circuit. Remove the thermostat cover and examine the button contacts for debris or oxidation. Clean with isopropyl alcohol and allow to dry before re‑assembly. If the problem persists, replace the button module as specified in the service manual.
A stuck “ON/OFF” toggle may be due to mechanical wear or a misaligned spring. Gently flex the switch to free the mechanism. If the toggle remains jammed, replace the switch assembly. After any repair, reset the thermostat to factory defaults to clear residual errors. Check wiring for grounding OK.
For malfunctions, consult the PECO support portal for firmware a updates or steps. Firmware upgrades can resolve bugs that manifest as display flicker or button latency. Power down the unit before performing replacement.
