General Operation
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IM-HC 561174 1120 Basic Heating Control
3.8 Boiler Control
3.8.1 Boiler Operation
When the Basic Heating Control determines that boiler operation is required,
the boiler contact terminals (5 and 6) close. While the boiler contact is
closed, the burner segment in the LCD is displayed.
3.8.2 Boiler Enable
Boiler Enable 30% / Boiler Enable 10%)
The Basic Heating Control has a DIP switch that allows for the selection
between a 30% boiler enable and a 10% boiler enable. In the 30% position,
the Basic Heating Control closes the boiler contact when the position of
the mixing valve exceeds 30%. The boiler contact remains closed until
the position of the mixing valve reduces below 15%. This setting would
normally be chosen for low mass boilers (copper fin tube, etc.), or systems
with low thermal mass in the loop between the boiler and the mixing valve
(recommended for most Viega applications).
In the 10% position, the Basic Heating Control closes the boiler contact
when the position of the mixing valve exceeds 10%. The boiler contact
remains closed until the position of the mixing valve reduces below 5%.
This setting is normally chosen for high mass boilers (cast iron, steel fire
tube, etc.) or systems with large thermal mass in the loop between the boiler
and the mixing valve.
Summary of Contents for IM-HC 561174 1120
Page 1: ...Installation Manual Viega Basic Heating Control ...
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