Tekmar 521 User Manual

Programmable Thermostat 521
Installation & Operation Manual
521
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D
12/20
Zoning Replaces: 01/14
© 2020 521_D - 12/20
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A Watts Water Technologies Company
The Programmable Thermostat 521 is
designed for three different modes of
operation: single stage heating, two stages
of heating with a fan, or one stage of
heating and one stage of cooling with
a fan. Two auxiliary sensors may be
added to measure the floor, outdoor or
room temperature. A Slab Sensor 079 is
included to measure floor temperature to
protect the floor from overheating and
enhance comfort. The programmable
schedule supports either a 7 day or 24
hour schedule with 2 or 4 events per day.
A permanent temperature hold button
overrides the programmable schedule.
An optional Adaptor Plate 012 is available
to allow the thermostat to mount onto a
single gang electrical box.
Introduction
Energy Saving Features
• 7 Day Programmable Schedule
Additional Features
• Optimum Start
• Permanent Temperature Hold
• Radiant Floor Heating
• Two Stage Heating
• Cooling
• Fan
• Backlight
• Outdoor and Floor Temperature
Display
• Time Clock
• Four Hour Battery-free Clock
Backup

Tekmar 521 Specifications

General

Category	Thermostat
Type	Programmable
Power Supply	24 VAC
Control Type	Digital
Display	LCD
Mounting	Wall
Stages	1 Heat / 1 Cool
Voltage	24 VAC
Programs	7-day programmable
Power Source	Hardwired
Temperature Range	5°C to 32°C