Application Guide

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© 2019 tekmar 671
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A - 08/19
Dedicated Boiler A671-1 Mechanical
Description
The WiFi Snow Melting Control 671 operates a boiler that is dedicated for the snow melting system. The system is piped in
primary-secondary to allow constant flow rates through the low-mass boiler and filled with glycol to prevent freezing.
• The system pump operates continuously when heating the slab during melting/idling/storm operation.
• The boiler pump cycles on and off together with the boiler.
• The slab temperature is controlled by cycling the boiler on and off.
• The slab target is determined by the melting/idling/storm setpoint and by the measured outdoor air temperature.
The system operation is dependent on sensor selection, as listed in the table below.
Sensor options Operation methods
Sensor Sensor Model(s)
Auto Start/
Auto Stop
Auto Start/
Timed Stop
Manual Start/
Timed Stop
Slab Temperature
Control
S1 Automatic Snow/Ice Sensor 090 or 094 • – • •
S2 Aerial Snow Sensor 095 – • • –
S3 Slab Sensor 072 or 073 – – • •
S2+S3 Aerial Snow Sensor 095 and Slab Sensor 072/073 – • • •
B1 = Boiler
P1 = System Pump
P2 = Boiler Pump
S1 = Snow/Ice Sensor 090 or 094
S2 = Snow Sensor 095
S3 = Slab Sensor 072 or 073
S4 = Outdoor Sensor 070
Legend
S4
671
Snow/Ice Sensor Options
B1
P2
P1
S2
S1
S3