Filter
Top Products
506468-01 Issue 1004 Page 22
System Diagnostic Module
4HP16LT units contain a diagnostic module for trouble-
shooting heat pump system failures. By monitoring and
analyzing data from the compressor and thermostat
demand, the module can accurately detect the cause of
electrical and system related failure without any sensors.
If a system problem occurs, a flashing LED indicator
communicates the failure code.
LED Description
POWER LED (Green) indicates voltage is present at the
power connection of the module.
ALERT LED (Yellow) communicates an abnormal system
condition through a unique flash code. The ALERT LED
will flash a number of times consecutively, pause, and
then repeat the process. The number of consecutive
Flash Codes
Table 10
flashes correlates to a particular abnormal condition.
TRIP LED (Red) indicates there is a demand signal from
the thermostat but no current to the compressor is de-
tected by the module. The TRIP LED typically indicates
the compressor protector is open or may indicate missing
supply power to the compressor.
Interpreting the Diagnostic LEDs
When an abnormal system condition occurs, the diagnos-
tic module displays the appropriate ALERT and/or TRIP
LED. The yellow ALERT LED will flash a number of times
consecutively, pause, and then repeat the process. To
identify a flash code number, count the number of con-
secutive flashes. Refer to Table 10 below and Table 11 on
page 20 for information on the flash codes.
Every time the module powers up, the last ALERT LED
flash code that occurred prior to shutdown is displayed for
DEL
sutatS
noitpircseDtluaF noitamrofnIgnitoohselbuorT
REWOP
)neerG(
rewopsaheludoMslanimreteludomtatneserpsiegatlovylppuS
PIRT
)deR(
dnamedtatsomrehT
,tneserpsi1Ylangis
rosserpmocehttub
gninnurtonsi
neposirotcetorprosserpmoC.1
erusserpdaehhgihrofkcehC*
egatlovylppusrosserpmockcehC*
nepositcennocsidrewoptinuroodtuO.2
neposi)s(esufrorekaerbtiucricrosserpmoC.3
tcatnocgnikamtonsirotcennocroeriwnekorB.4
metsysnitneserpfinepohctiwserusserpwoL.5
nepodeliafsahrotcatnocrosserpmoC.6
TRELA
)wolleY(
hsalF
1edoC
miTnuRgnoLee
e
ee
sirosserpmoC
gninnur
nurgnolylemertxe
selcyc
noelbacilppatoN(
)sledompmuptaeh
--
TRELA
)wolleY(
hsalF
2edoC
metsyS
pirTerusserP
noitcusroegrahcsiD
erusserp
rostimilfotuo
rosserpmoc
dedaolrevo
erusserpdaehhgiH.1
metsysnitneserpfihctiwserusserphgihkcehC*
tnaregirferhtiwdegrahcrevosimetsysfikcehC*
metsysnielbasnednoc-nonrofkcehC*
)degamad,dekcolb,ytrid(noitalucricriaroopliocresnednoC.2
gninnurtonsinafresnednoC.3
roticapacnafkcehC*
srotcennocdnagniriwnafkcehC*
egakcolbroeruliafrofrotomnafkcehC*
egakaellaitnatsbussahtcudrianruteR.4
ofni1edoChsalFkcehc,metsysnitneserphctiwserusserpwolfI.5