tekmar 518 Thermostat Installation - Manual (Page 11)

© 2013 518_D - 03/13
11 of 12 A Watts Water Technologies Company
Technical Data
Thermostat 518 One Stage Heat
Literature 518_C, 518_D, 518_Q, 518_U
Control Microprocessor control. This is not a safety (limit) control
Packaged weight 0.53 lb. (240 g)
Dimensions 3-11/16” H x 3” W x 15/16” D (94 x 76 x 24 mm)
Enclosure White PVC plastic, NEMA Type 1
Approvals Meets Class B: ICES & FCC Part 15
Ambient conditions Indoor use only, 32 to 122°F (0 to 50°C), RH ≤90% non-condensing
Power supply
10 to 30 V (ac/dc), 50/60 Hz, 1.8 VA standby,
56 VA max fully loaded, Class 2
Relay 30 V (ac/dc) 2 A, Class 2 circuits
Sensor NTC thermistor, 10 kΩ @ 77°F (25°C ±0.2°C) ß=3892
– Included None
– Optional tekmar type # 070, 072, 073, 076, 077, 079, 084
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.