Page 38
Legacy
™
Model LRZM Pool/Spa Heater Installation and Operation Manual
open circuit, or readings outside of the range stated
above, replace the controller. If the control is working
correctly, reconnect the wires to the circuit board.
10.4.7.3 Temperature Sensor
The temperature sensor is a 0-20,000 ohm
thermistor. Set your ohmmeter to the 0-20K range.
The meter readings will depend on the temperature of
the water in the header. See Table 9 for approximate
readings at various temperatures.
To test the temperature sensor, circulate water
through the heater for
fi
ve (5) minutes. Remove the
temperature sensor wires from the temperature control
board. Place one lead of the meter on each wire of the
temperature sensor (test points 20 & 21). Record the
reading. Measure and record the water temperature
of the pool near the inlet of the
fi
lter system. Find
the temperature in the chart that is closest to your
temperature reading of the pool water. Compare your
ohmmeter reading to the resistance number in the
chart. Remember that this is an approximate reading
and numbers may vary. If your reading is close to the
numbers indicated in the chart then the temperature
sensor is working correctly. Reconnect the wires to
the circuit board. If your reading is vastly different or
outside of the ranges shown the temperature sensor
should be replaced.
Table 9. Temperature Sensor
WATER TEMP. IN
HEADER °F (°C)
APPROX. RESISTANCE IN 1000'S
OF OHMS (kOhms)
50 (10)
19.9
60 (15)
15.3
70 (21)
11.9
80 (26)
9.3
90 (32)
7.3
100 (38)
5.8
10.4.7.4 Temperature Control Circuit Board
With the red lead of the meter still at test point
1, place the black lead of the meter on the TH/PP
terminal of the temperature control circuit board (test
point 15). If there is more than 220mVDC at this point
but not at the TH terminal of the temperature control
circuit board (test point 16) as tested in section 10.4.7,
then the control circuit board is faulty. Replace the
board.
Section 11. Replacement Parts
11.1 Ordering
Information
To order or purchase parts for the Legacy pool
and spa heater, contact your nearest Jandy dealer or
distributor. See the web site at www.jandy.com for the
nearest service center. If they cannot supply you with
what you need, contact Customer Service at Zodiac
Pool Systems, Inc., Telephone (800) 822-7933.
NOTE
To supply the correct part it is important that
you state the model number, serial number
and type of gas when applicable. This
information is on the rating plate inside the
heater.
The following pages contain a parts list, general
exploded view, and detailed exploded views to aid in
pats identi
fi
cation. Pleas refer to these pages when
ordering parts for your Legacy pool/spa heater.
All trademarks used herein are the property of their respective owners.
Summary of Contents for Legacy LRZM
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