Installation & Operation Manual 518_D Thermostat 518 06/16 Zoning Replaces: 03/13 Introduction The Thermostat 518 accurately controls the room temperature for a hydronic heating zone using Pulse Width Modulation (PWM) technology. Simple up and down buttons and a display with large type make this thermostat easy to read and use. The 518 automatically detects a single auxiliary sensor to measure either outdoor, floor or remote room temperature.
Table of Contents Important Safety Information...........2 Installation............................................3 Preparation......................................2 Removing The Thermostat Base.....3 Mounting The Thermostat................4 Thermostat Wiring...........................5 Testing the Thermostat Wiring.........6 User Interface.......................................7 Home Screen...................................7 Symbols Description........................7 Sequence of Operation............
• It is the installer's responsibility to ensure that this thermostat is safely installed according to all applicable codes and standards. • Improper installation and operation of this thermostat could result in damage to the equipment and possibly even personal injury or death. • This thermostat is not intended for use as a primary limit control. Other controls that are intended and certified as safety limits must be placed into the control circuit.
Mounting The Thermostat To prevent the risk of personal injury and/or death, make sure power is not applied to the thermostat until it is fully installed and ready for final testing. All work must be done with power to the circuit being worked on turned off. Please be aware local codes may require this thermostat to be installed or connected by an electrician.
Thermostat Wiring Zone Valve----------------------------------------------------------Install field jumper wire R to Rh Zone Valve Optional Slab Sensor 079 NoNo Power Power R C 518 C R Rh W1 S1 Com Away 24 V (ac) Transformer 009 Do not over tighten wiring screws. Hand tighten only.
Thermostat Wiring Switching Relay------------------------------------------------------ Optional Slab Sensor 079 518 R W Zone 1 R W Zone 2 R W Zone 3 24 V Com Class 2 Transformer Switching Relay X X Zone 1 H N Zone 2 H N Pump Zone 3 H N N NoNo Power Power C R Rh W1 S1 Com Away Do not over tighten wiring screws. Hand tighten only.
User Interface Home Screen Away Symbols Description HEAT ON Heat is turned on. MIN The floor is at or below the floor minimum temperature. MODE OFF The heating system is off. MAX The floor has reached the floor maximum temperature. WARNING SYMBOL Indicates an error is present. AWAY Operating at the away temperature.
Sequence of Operation Heating Operation Push the or button to select a preferred temperature setting. The Heat On symbol is shown on the display when the thermostat is heating. The heat can cycle on and off within +/- 1.5°F (1°C) of the temperature setting. The floor and air heating can be shut off by holding the button until Set Room is Off. To resume heating when the Mode is Off, press the button to navigate to the Mode setting, then press the button to select Mode Heat.
Programmable Settings Setting Display User settings. Press the and advance to the next setting. buttons together for 3 seconds to enter and MODE Select heat or off. Range: HEAT, OFF Default: HEAT UNITS Select the temperature units. Range: °F or °C Default: °F LIGHT Select when the display back light should operate. Auto operates the backlight for 30 seconds after a keystroke. Range: OFF, AUTO, ON Default: AUTO SET FLOOR Set the floor minimum temperature.
Troubleshooting Error Messages Error Message Description SETUP MENU SAVE ERROR The thermostat failed to read the Programmable Settings from memory and has reloaded the factory default settings. The thermostat stops normal operation until all Programmable Settings are checked except to provide freeze protection. Room Room ROOM SENSOR OPEN CIRCUIT ERROR The built-in air temperature sensor has an open circuit fault. Do not confuse this error with the auxiliary room sensor short circuit error.
Frequently Asked Questions Symptom Look for... Corrective Action Display powering on and off. Measure voltage at wiring terminals R and C. The power supply transformer may have limited VA capacity. A transformer with a larger VA rating is recommended. Thermostat does not heat. Mode Off Thermostat must be in Mode Heat in order to provide heating. Technical Data Thermostat 518 One Stage Heat Literature 518_C, 518_D, 518_Q, 518_U Control Microprocessor control.
Limited Warranty and Product Return Procedure Limited Warranty The liability of tekmar under this warranty is limited. The Purchaser, by taking receipt of any tekmar product (“Product”), acknowledges the terms of the Limited Warranty in effect at the time of such Product sale and acknowledges that it has read and understands same.
