Taylor RGFG, Руководство по установке

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55
wire the thermostats for each of the
configurations below.
In non-communicating systems, the
heating cycle is always initiated by a 24
volt signal on W1. When the controller
senses 24 volts on W1, the following
sequence occurs:
MODULATING FUNCTION:
(Modulating function with a non-com-
municating thermostat only applies
when both switches S4-2 and S4-3 are
in the “OFF” position and a non-com-
municating modulating thermostat
(specified for use with the furnace) is
installed as shown in Figures 53-55.)
After the warm-up period, the furnace
will respond to the thermostat demand
by adjusting the gas valve pressure
and blower speed between 40% and
100% of maximum heating capacity.
TWO-STAGE FUNCTION:
Two-stage thermostat yields 3 stages
of heat.
(Two-stage function only applies when
both switches S4-2 and S4-3 are in
the “ON” position and a two-stage
thermostat is installed as shown in
Figure 57.)
After the blower on-delay period, the
furnace will respond to the thermostat
demand by adjusting the gas valve
pressure and blower heating speeds to
the “W” signal values. “W1” only = 40%
gas valve pres sure and blower heating
speed. “W2” = 65% gas valve pressure
and blower heating speed for the first
five minutes and 100% thereafter.
FURNACE OPERATION
USING NON-COMMUNICAT-
ING MODULATING, SINGLE-
STAGE, AND TWO-STAGE
THERMOSTATS (CONSULT
THE SECTION OF THIS
DOCUMENT TITLED NON-
COMMUNICATING THER-
MOSTATS FOR WIRING DIA-
GRAMS)
The modulating furnace is capable of
operating with a single-stage or a two-
stage thermostat as well as the modu-
lating thermostat or fully communicating
thermostat specified for use with the fur-
nace. Fully communicating thermostat
functions and operations are explained
in detail in the sections of this manual
titled COMMUNICATING SYSTEMS
and THERMOSTATS (under the sub-
section titled COMMUNICATING THER-
MOSTATS).
Based on the dipswitch settings of S4-2
and S4-3, the furnace will operate with
either single-stage or two-stage ther-
mostats as a modulating system using
an algorithm that utilizes three distinct
firing rates; 40%, 65% and 100% of the
furnace heating capacity (See below for
opera tion of each). See Figure 41 to
determine which dipswitch settings are
necessary for operation with a modulat-
ing, single-stage or two-stage thermo-
stat.
See the section of this document titled
THERMOSTATS (under the sub-section
titled NON-COMMUNICATING THER-
MOSTATS) for information on how to
Also, if the call for heat ends, the
furnace terminates at the present
rate.
SINGLE-STAGE FUNCTION (“W”
signal only) :
One-stage thermostat will yield 3
stages of heat.
(Single-stage function only applies
when both switches S4-2 and S4-3
are in the “OFF” position and a
single-stage thermostat is installed
as shown in Figure 56.)
After the blower on-delay period, the
furnace will respond to the thermo-
stat demand by altering the gas
valve pressure and blower speed as
follows:
Phase 1: 0 to 5 minutes = 40% of
furnace capacity (gas valve output
and blower speed)
Phase 2: 5 to 12 minutes = 65% of
fur nace capacity (gas valve output
and blower speed)
Phase 3: After 12 minutes = 100%
of fur nace capacity (gas valve out-
put and blower speed)
NOTE: If the call for heat ends dur-
ing any phase, the furnace will ter-
minate imme diately at the firing rate
of that phase.
S5
S5-1 = ODD “ON” or “OFF” select.
This switch will ignore the input from
the 24 volt terminal labeled “HUM
STAT” during cooling when in the
“OFF” position. However, the “HUM
FIGURE 42
DIPSWITCH BANK S5 COOLING / O.D.D. SELECT
ST-A1171-01