Application Brochure

© 2013 654_A - 06/13 6 of 16
Single Zone with Modulating Steam Valve A654-3 Mechanical
Description
A Snow Melting Control 654 operates a modulating steam valve and a system pump. The heat source may be either district
steam or a steam boiler. The slab temperature is controlled by adjusting the steam valve position using an analog 0 to 10
V (dc) or 4 to 20 mA signal. The slab is heated to maintain the slab target temperature. When a Snow / Ice Sensor 090 or
094 is installed, the system automatically starts when snow or ice is detected and continues to run until the slab is dry. When
a Snow Sensor 095 is installed together with a Slab Sensor 072 or 073, the system automatically starts when snow is detected
and runs on a timer before shutting off. All systems can be manually started and shut off using a timer when either a Snow /
Ice Sensor 090 or 094 or a Slab Sensor 072 or 073 is installed.
Snow or Ice Detector
Option Start and Stop Sequence Sensors Required (sold separately)
1 Auto start / Auto stop Snow / Ice Sensor 090 or 094
2 Auto start / Timed stop Snow Sensor 095 & Slab Sensor 072 or 073
3 Manual start / Timed stop Slab Sensor 072 or 073
Application Settings
Setting Name Value
APP MODE MIX
BOIL TYPE OFF
AUX RELAY SYS (system pump)
Outdoor
Sensor 070
Relay 003
Mix
Supply
Sensor
082
District Steam
System
Pump
Modulating
Steam Valve
654
Option 1
Snow / Ice Sensor
090 or 094
Option 2
Snow Sensor 095 and
Slab Sensor 072 or 073
Option 3
Slab Sensor
072 or 073
Recommended Accessories
Qty Part Name Part Number
1 Relay 003
1 Transformer 009