Weil-McLain Aqua Logic, Product Manual, Page: 33 / 44

A
QUA
L
OGIC COMPANION WATER HEATER
—
Product Manual
Troubleshooting
(continued)
Excessive domestic water temperature
1 Adjust WM97+ control settings and check operation.
s Follow instructions in the boiler manual and this manual to adjust tank temperature
and boiler water temperature.
s If controls are set properly, check tank sensor installation and operation.
s See the illustration at right for locations of the sensor wells. The lower well is on the
side opposite the DHW connections. (This illustration shows a right-oriented tank.)
s Check whether sensors are inserted completely into their wells. If not, press in firmly
and recheck Aqua Logic (CWH) operation.
s If sensors are properly inserted in their wells, disconnect each sensor harness and
attach an ohmmeter. The table below shows the correct values for the sensor at
various temperatures.
Temp
(°F)
Sensor ohms Temp
(°F)
Sensor ohms Temp
(°F)
Sensor ohms
Min Max Min Max Min Max
34265 37871 8504 9399 2517 2782
27834 30764 6847 7568 2091 2311
21630 23907 5545 6129 1744 1928
16944 18727 4517 4992 1461 1615
13372 14780 3698 4088 1229 1359
10629 11747 3043 3364 1038 1147
s Use the resistance values at 32°F, 60°F, 70°F and 212°F to
measure the sensor resistance at known temperatures
(ice point, room temperature and sea level boiling
point). For ice point and boiling point, insert the sen-
sor in water at that temperature. Use an ohmmeter to
read resistance value. To check whether the WM97+ control is correctly sensing temperature, you can use
a resistance decade box. Connect the decade box tem-
porarily in place of a sensor and read the correspond-
ing temperature on the WM97+ control display. The
temperature should be close to the value corresponding
to the input resistance.
2 Recirculation loop needed?
s
Installing a properly-sized recirculation loop will not
only provide prompt delivery of hot water, but it will provide circulation and mixing of the water within
the tank.
3 Thermostatic mixing valve set too high?
s Follow instructions in the mixing valve manual to
check mixing valve setting temperate. Adjust if neces- sary following the manual’s specified procedure.
4 No thermostatic mixing valve installed or mixing valve is defective?
)&4(% -)8).' 6!,6% )3 ./4 ).34!,,%$
$)3#/.4).5%53%/&4(%!QUA,OGIC#7(
!.$).34!,,4(%-)8).'6!,6%&/,,/7).'
).3425#4)/.3 ).4()3 -!.5!, !.$4(%
-)8).'6!,6%-!.5!,
s
The Aqua Logic (CWH)
MUSTNOT
be operated without
a mixing valve installed per the instructions in this
manual and the mixing valve manual.
s Follow instructions in the mixing valve manual to
check valve operation. If valve is correctly installed and
does not operate correctly, replace the mixing valve.
Part number 635-500-156/1113
33