Weather-Rite TT Series, Инструкция по установке, эксплуатации и обслуживанию

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TT-S
ERIES
I
NSTALLATION
, O
PERATION AND
S
ERVICE
M
ANUAL
168 of 198
27.7 Series 94 - Preliminary Circuit Analysis
In order to diagnose the ca u se of pro b lems in this
system it is necessary to determine certain v al u es. It
is helpf u l to ha v e a v olt/ohm m u ltimeter.
Mod u lation F u nction: If sensed temperat u re
(controller display) is less than minim u m dial setting
temperat u re, perform Step 1 b elo w ; other w ise
contin u e on to Step 2.
Temperat u re Sensor F u nction: Perform the entire
"Mod u lation F u nction" analysis, implementing Step 1.
(Step 1 isolates the sensor f u nction from the
system).
1. Disconnect the sensor w ires to terminals
(amplifier - 8 and 9, amplifier/selector - 1 and
2) and replace
w ith s u pplied test resistor or
w ith other means to o b tain a resistance v al u e
falling w ithin the temperat u re range to b e
tested, referencing temperat u re ta b le b elo w .*
2. Connect a DC v olt meter to terminals 3 and 4,
or at the M/MR v al v e terminals. Do not discon-
nect existing w iring.
3. Rotate temperat u re dial kno b to maxim u m set-
ting - the DC v olts sho u ld read at least 17.5 V
DC. Rotate temperat u re dial kno b to minim u m
setting - the DC v olts sho u ld read no more than
2.0 V DC. DC v oltage sho u ld grad u ally
increase as the dial temperat u re setting is
slo w ly rotated u p to and past the controller's
digital display temperat u re.
Table 43: Resistance/Temperature Table
Approximate controller display temperature with 1100 to 1800
ohms resistance across terminals (amplifier - 8 and 9, amplifier/
selector - 1 and 2).
27.7.1 Series 94 - Temperature Calibration
Occasionally the set point that is indicated on the
dial does not match the LED display. This is
u s u ally a
indication that cali b ration is req u ired. To cali b rate the
set-point controls, follo w the steps listed b elo w . The
LED display is to b e considered master, d u ring these
steps.
27.7.1.1 Calibration of Spray Temperature Selector
NOTE: Cali b ration can not b e done if room
temperat u re is 90 °F or higher.
1. Place the S u mmer/Off/Winter s w itch in the
Winter position.
2. Loosen the setscre w that holds the kno b to the
shaft of the selector.
3. Rotate the kno b , taking care not to mo v e the
shaft, in the direction needed to align the dial
setting to the LED display.
4. Tighten do w n the setscre w .
• Cali b ration is no w complete.
27.7.1.2 Calibration of Dry Temperature Selector
1. Acti v ate the dry cycle.
2. Place the S u mmer/Off/Winter s w itch in the
Winter position.
3. Loosen the setscre w that holds the kno b to the
shaft of the selector.
4. Rotate the kno b , taking care not to mo v e the
shaft, in the direction needed to align the dial
setting to the LED display.
5. Tighten do w n the setscre w .
• Cali b ration is no w complete.
R (ohms) T (de g rees)
1,100 78 °F (25 °C)
1,200 125 °F (50 °C)
1,300 172 °F (80 °C)
1,400 220 °F (100 °C)
1,500 270 °F (130 °C)
1,600 15 °F (160 °C)
1,700 365 °F (185 °C)
1,800 410 °F (210 °C)