Specifications
If no voltage is detected at test point 7, the roll-out
switch (fusible link) or vent temperature limit has
failed. This indicates higher than normal temperatures
in the component compartment (vestibule). The normal
component compartment temperature is well below
300°F (149°C). The roll-out switch (fusible link) is
designed to fail at temperatures above 305°F (152°C).
Excessive temperature might be due to a blocked ue
or heat exchanger. Clean the heat exchanger and clear
the ue and vent of any restrictions. Sometimes the
roll-out switch (fusible link) fails due to ame roll-out.
Flame roll-out may be caused by delayed ignition or
downdrafting in windy areas. Thoroughly investigate the
causes for ame roll-out and correct the problem when
replacing the roll-out switch (fusible link). The vent
temperature limit will fail due to abnormal temperatures
in the vent system. Excessive temperatures will cause
the switch to open. The vent temperature limit is
designed to fail at temperatures above 464°F (240°C).
Excessive temperatures can be caused by inadequate
water ow or a damaged heat exchanger. Thoroughly
investigate the causes for roll-out switch (fusible link)
failure and correct the problem when replacing the vent
temperature limit.
10.4.3.5 Temperature Limit Switches Circuit
Since the limit switches are not easily accessible,
the voltage can be checked at the two legs of the circuit
at the controller. See test points 8 and 9 in Figure 30.
Check the voltage at test point 8. If there is
not 20-28 Volts AC nominal at this point, either the
controller or the two-pin wire harness is faulty, or one
of the two safeties (water pressure and fuselink) before
it are open. If 20-28 Volts AC nominal is detected at
this point, then move the red lead of the meter to test
point 9 where the black wire from the 130°F (55°C)limit
enters the two-pin connector. If 20-28 Volts AC nominal
is detected at this point, the devices in this circuit are
closed and the circuit is working properly.
If there is no voltage, one of the limit switches
is open. This is normally due to excessive water
temperature, which should be thoroughly investigated
before replacement of limit switches. Excessive water
temperature may be caused by low water ow. Water
ow deciency may be due to obvious problems such as
a defective pump or blocked water lter. Alternatively,
excessive water temperature may be due to over-ring,
or to a problem with the water piping or the heater's
internal bypass control. Over-ring might be a result
of an incorrect gas orice or supply of propane gas to a
heater intended for natural gas.
If there are no such fundamental problems, identify
which of the switches is open. Limit switch access is
through the limit switch plugs on the side of the heater
to which water pipes are connected. Remove the limit
switch plugs from the bottom of the header and gently
remove the switches from the wells.
Note that the limit switches have different trip
points, and it is important that replacements are correct.
The 150°F (65°C) switch has a red dot on the top of
the switch, and is closest to the heater jacket, must be
installed in the lower well in the header. The 130°F
(55°C) switch has no dot, and is farthest from the heater
jacket. must be installed in the upper well in the outlet
of the header.
Move the red meter lead to the terminal connection
on the 150°F (65°C) switch that is connected back to
the controller. The voltmeter should read 20-28 Volts
AC nominal. No voltage here means that the two-pin
wire harness is bad and should be replaced. If voltage
is detected at this point move the lead to the other
terminal of the switch. If the voltmeter does not show
voltage then the 150°F (65°C) limit is bad and should
be replaced. If the meter reads 20-28 Volts AC nominal,
move the lead to the terminal of the 130°F (55°C) limit
that is connected to the wire that jumps between the two
limit switches.
No voltage here means that the wire assembly is
bad and needs to be replaced. 20-28 Volts AC nominal
shows that the wire between the two limits is making
a good connection. Now move the lead to the other
connection terminal on the 130°F (55°C) limit. No
voltage at this point indicates that the limit switch has
failed and needs to be replaced. Voltage here would
show that the limit is good and that the two-pin wire
harness may have a bad connection. Replace the wire
harness, if necessary.
10.4.3.6 Gas Valve Voltage
The gas valve will operate only when there is a
call for heat, all safety circuits have been satised and
the hot surface igniter has had power for appoximately
35 seconds. If the gas valve does not operate under
these conditions, check the voltage going to the gas
valve. Place one voltmeter lead on the connector on the
ignition control where the yellow wire is connected (test
point 16). Touch the free lead of the meter to the gas
valve terminal where the brown wire is attached at the
gas valve. This test point will have voltage present only
during a trial for ignition or during normal operation.
The meter should read 20-28 Volts AC. If there is no
voltage, then there is a bad connection between the gas
valve and the ignition control. Replace the wire harness.
Listen closely to the gas valve when it is rst
energized (24V rst appears at test point 15 during the
trial for ignition). There should an audible "click" when
the valve opens.
If there is voltage at the gas valve terminal where
the brown wire is attached, but the gas valve does not
open, replace the valve.
Page 39
ENGLISH
Jandy
®
Legacy™ Model LRZE Pool/Spa Heater by Zodiac
®
|
Installation and Operation Manual