Electric heat for fan
coil units
For AppStat fan coil models that support both on/off and modulating valves,
electric heat can be added to two-pipe systems. Typically this heat is a duct or
baseboard resistance heater controlled by a relay.
When the supply water type is chilled water and there is a call for heat, the
AppStat controls the heating element through output terminal BO5. The
output turns on when the heating loop is greater than 99%. The output is
turned off when the loop falls to 5%. If the supply water type is hot water,
only the water valve output is used to satisfy a call for heat.
Fan operation for
fan coil units
The AppStat supports both modulating fans and fans with one, two, or three
speeds. Speed for either type of fan is determined by the PID loop that is
currently controlling the heating or cooling. Fan speed control is set up from
the user interface by a user with Password 2. See the topic
.
One, two, and three speed fans
For one, two, and three speed fans, the AppStat controls the fan speed with
terminals FAN-L, FAN-M, and FAN-H.
Single speed fans use terminal FAN-L only
Two speed fans are controlled with terminals FAN-L and FAN-H
Thee speed fans use terminals FAN-L, FAN-M, and FAN-H
The fan output terminals are energized as the cooling or heating loop varies
from 0-100%. Terminal activation is shown in the following table.
Fan L terminal
Fan M terminal
Fan H terminal
Fan
speed
On
Off
On
Off
On
Off
One
Active valve
5%
n/a
n/a
n/a
n/a
Two
Active valve
5%
n/a
n/a
95%
80%
Three
Active valve
5%
65%
50%
95%
80%
Table 5–1
Fan speed
Modulating fans
The fan starts a modulation fan on a call for either heating or cooling. The fan
runs at the minimum fan speed until the heating or cooling loop reaches 50%.
From 50% to 100% of the loop, the fan speed ramps from the minimum speed
to maximum speed. The minimum and maximum fan speeds are set from the
Section 5: Sequences of operation
KMC Controls, Inc.
72
Revision G
Содержание BAC-4000 series
Страница 6: ...Contents KMC Controls Inc 6 Revision G ...
Страница 30: ...Section 2 Installing the AppStat KMC Controls Inc 30 Revision G ...
Страница 64: ...Section 4 Commissioning functions KMC Controls Inc 64 Revision G ...
Страница 112: ...Section 6 Application drawings KMC Controls Inc 112 Revision G ...
Страница 124: ...Section 7 System integration KMC Controls Inc 124 Revision G ...
Страница 128: ...power 28 roof top unit 98 rough in 18 Index KMC Controls Inc 128 Revision G ...