Carrier 42BVC Fan User Manual


 
5
Thermostats — Three thermostats are available for field
installation:
Honeywell T834C manual changeover, single-stage heat
thermostat features:
off-cool-heat system switch
on-auto fan mode switch
single-stage electric heat
outside air signal
Honeywell T8500 digital, automatic/manual changeover,
2-stage heat thermostat features:
digital display of temperatures and all functions
off-cool-heat-auto system mode buttons
single speed fan operation
on-auto fan mode button
single or two stage electric heat signal
outside air signal
remote temperature sensor available
Sunne T170 single-stage heat, 2-pipe heat/cool auto
changeover thermostat features:
digital display of ambient temperature and operating
mode
single fan speed operation, power and operating mode
buttons
continuous fan operation, cycling water control valve
4-pipe ACO/MCO (automatic changeover/manual
changeover) with “on-auto” fan mode button
one or 2 stage electric heat signal available
purge cycle and temperature sensor for 2-pipe cold
water/hot water systems
programmable operating range, dead band, digital dis-
play, temperature set-back
THERMOSTAT FUNCTIONS
LEGEND
Valve packages — Valve packages are factory assembled
for field installation. Motorized valves (24 v) can be operat-
ed with power on with spring return or power off/power
on.
It is recommended that basic motor controls are ordered
when valve packages are ordered.
SYSTEM FUNCTION CHANGEOVER
THERMOSTATS
Honeywell
T834C
Honeywell
T8500
Sunne
T170
2Pipe HW-Heat Only ACO XX
2 Pipe CW-Cool Only ACO XX
2Pipe
CW/HW
Heat/Cool
MCO ——X
ACO ——X
2Pipe
CW/HW
Heat/Cool with
Aux. Electric Heat
MCO ——X
ACO ——X
2Pipe
CW-Cooling with
To t al Electric Heat
MCO X X X
ACO XX
4Pipe
CW/HW
Heat/Cool
MCO X X X
ACO XX
ACO Automatic Changeover
Aux Auxiliary
CW Chilled Water
HW Hot Water
MCO Manual Changeover