4387535 Whirlpool Refrigerator Compressor Relay Andâ Overload Start⤠Kit is a⢠combined âstarting and protectiveâ assembly used âon sealed refrigeration⢠compressors;â it typicallyâ comprises a start â˘relay â¤(or â¤PTC âŁstart device) and a thermal overload protector,â often â¤supplied as a wired kit with theâ terminal⣠plug and mounting⣠hardware. As a âdiscrete electromechanical/electronic component, âit is designed to provide⤠the brief high-torque current neededâ to bring the compressor motor up to speed and to interrupt current when the â¤motor draws excessive âamperage or reachesâ a⤠damaging temperature.
Inside⤠the appliance the â˘relay and overload sit â¤in the compressor start circuit and directly interface with the âŁcompressor’s âstart and run windings,â the appliance control â˘(thermostat or electronic control board)and âthe incoming â¤mains.The âstartâ element momentarily âcouples â¤the start⢠winding to provide starting âtorque and then drops out once the âmotor is at âoperating speed; the overload âelementâ monitors â¤motor current/temperature âand opens the circuit to prevent â¤locked-rotor damage or thermal failure. Physically, thes âparts âare mounted on⣠or â¤near theâ compressor terminal âcover and are integralâ to âreliable compressor starting âand⣠continued â¤motor protection.
This article⢠explains âhowâ the 4387535 kit âfunctionsâ within the refrigeration system, describes typical compatibility⤠and electrical characteristics âto â˘check whenâ selecting âaâ replacement, â¤and⤠outlines âŁcommon failure âsymptoms â(such as,⤠a humming compressor, failure âto âstart, ârapid on/off⤠cyclingor âevidenceâ of⣠overheating).It will âŁalso cover practical troubleshooting approaches a technician or â˘appliance owner can use to isolate start-relay versus overload⣠faultsand the replacement â˘considerations toâ ensure correct â¤terminalâ arrangement, ratings matchandâ safe installation practices when fitting aâ newâ relay/overload kit.
Tableâ of⣠Contents
- Function âand Role of the⤠Compressor Relay and Overload â¤Start Kit in â¤Whirlpoolâ Refrigerators
- How the⢠4387535 Whirlpool Refrigeratorâ Compressorâ Relay And Overload Start âKit Operates Within⤠the Compressor Start Circuit
- Diagnostic Indicators and Commonâ Failure Symptoms of a Faultyâ Relay and Overload Assembly
- Compatibility, Replacement Considerationsand Installationâ Procedures for Field Service Technicians
- Q&A
- To â¤Conclude
Function â˘and Role âŁof the Compressor Relay and Overload Start Kit âinâ Whirlpool Refrigerators
The 4387535â Whirlpool Refrigerator Compressor Relay â˘And Overload Start Kit is a âŁcombined electrical assembly that enables reliable compressor âstarting while protecting the âmotor fromâ thermal⤠and current-related â¤fault conditions. The relay portion providesâ the initial connection to the compressor’s start⣠winding (or engages a PTC/start device), producing the required inrush⤠torque to bring the âcompressor⢠up to running speed, â¤then drops out toâ leave the ârun winding energized.the overload protector is a⢠temperature- or current-sensitive âdevice placed in series âŁwith theâ compressor; âit opens the â¤circuit during â˘prolonged high-current conditionsâ or excessive internal heat toâ prevent winding damage and automatic⣠resets âonly after the âdevice cools to its specified recovery point.
Technicians should match this kit to the compressor’s terminal configuration and rated trip characteristics rather than relying⣠solely on â˘casing âfit; electrical⢠ratings determine whether â¤the relay will supply adequate startingâ torque andâ whether the â¤overload will protect withoutâ nuisanceâ trips.â Common field âindicators that this⢠assembly âisâ failing include repeated⣠clicking at start-up, a humming â¤compressor that does not start,⣠or â˘repeated trips ofâ the overload with âŁno external âcause; these symptoms⤠often appear â¤when windings remain electrically intact but cannot be âengaged or are being repeatedly⤠exposed â˘to⣠stall current. âŁThe kit corrects start-and-protect behavior but will â˘not repair â¤a compressor with shorted or open windings, â¤so bench measurements â(resistance and inrush⢠current) and âproper part⣠selection remain essential â˘for a durable⤠repair.
- Primary âfunction:â provide âstart âtorque and thermal/current âprotection
- Behavior: momentary startâ engagement, sustained run on run⢠winding, protective open on fault
- Typical â˘symptoms of failure: clicking, hummingâ without start, tripping overloads
- Compatibility considerations: match â¤terminal âlayout, âcurrent ratingand⤠reset characteristics
| item | Description |
|---|---|
| Function | Start relay âŁsupplies inrush/current âŁto start â˘winding; â˘overload opens on overcurrent/overtemperature |
| Behavior | transient engagement at start, series â˘protection during operation, auto-reset â˘after cool-down |
| when⢠to âreplace | Repeated start failures with intact windings, audible clickingor frequent thermal trips |
How âthe â4387535 Whirlpool⢠Refrigerator Compressor Relay And Overload Start⣠Kitâ Operates Within the â¤Compressor âStart Circuit
The 4387535 Whirlpool⣠Refrigerator Compressor Relay âAnd Overload Start kit provides the switching âelement and thermal protection⤠that âŁcontrol how the compressor’sâ start winding â¤isâ energized during⢠each âstart cycle.⤠When line voltage is applied, â¤the âŁrelay âmomentarily connects the start winding (or introduces a lower-resistanceâ path) to⤠produce â˘the higher starting torque required to spin the compressor ârotor;⤠once the rotor reaches near-run speed⤠the âŁrelay⤠opens â¤to remove⤠the⣠start circuit and the âŁcompressor continuesâ on⢠the run winding. the overload device is wired in series with the compressor circuit â˘and senses sustained overcurrent or excessive temperature, opening the circuit â˘to âprotect âŁthe motor from⣠locked-rotor âŁdamage⤠or thermal stress âand then â˘resetting only â¤after the⢠unit cools â˘below its trip threshold.
In practical service, this â˘kit mustâ match⢠the compressor terminal layout and electrical ratings to behave⤠correctly; a wrong relay timing or â˘an overloadâ with âan inappropriateâ tripâ curve will cause hard starts, nuisance tripsor motor⢠damage. â¤Typical failure âmodes include a stuck relay (start winding permanentlyâ connected),⢠a relay that never closes â(compressorâ hums âbut won’t start),⣠and anâ overload that opens âprematurely after a short run. Technicians verify⢠operation by checking terminal â¤continuity, measuring⢠coil/resistance values, âand observing whetherâ theâ compressor transitions from start to run; swapping with a known-good relay/overload âassembly â˘is â¤a common diagnostic stepâ when wiring âand âsupply voltages are⤠confirmed correct.
- Common â¤symptoms ofâ relay/overload â˘issues: humming compressor, intermittent starts, repeated overload trips.
- Key compatibilityâ checks: matching⤠terminal âŁIDs, voltage/amperage ratingsand âphysical mounting⢠clip.
- Service⣠actions:⣠continuity andâ resistance checks, timed start observationandâ controlled âŁcomponent substitution forâ diagnosis.
| Item | Description |
|---|---|
| Relay | Connects⤠the⢠start windingâ brieflyâ at âŁpower-up to provide âstarting torque; â˘may âbe PTCâ or mechanical. |
| Overload | Series âthermal/current protector that opens âŁon sustainedâ overcurrent or overheating andâ resets after cooling. |
| Terminals | Typical labels:⤠C â(common), S (start), âR (run); âŁcorrect mapping is required⤠for proper â˘operation. |
Diagnostic Indicators and Common Failure Symptoms of a Faulty Relay and Overload Assembly
The 4387535⣠whirlpool Refrigerator Compressor Relay And âOverload Start â¤Kit ⣠combines a start relay âand thermal overload⣠protector to manage the compressor’s start â¤sequence and to disconnect the motor under⢠sustained âŁovercurrent or overheating conditions. The start relay momentarily applies the compressor’s start winding toâ produce the high starting torque; âthe âŁoverload monitors⤠current andâ temperature andâ will open âthe circuitâ if the âcompressor draws âŁexcessive current or the â˘motor⤠housing⣠rises above safe limits. On compatible⢠Whirlpool âcompressor assemblies the ârelay must disengage cleanly after the start interval and theâ overload must âremain closed during normal running – intermittent contact, stuck relay platesor â˘a degraded⢠bi-metal element in the overload can mimic a failed⢠compressor by âŁpreventing normal⣠starting or by causing repeated cycling â˘under load.
- Repeated â¤clicking at âthe â˘compressor âwith no ârun – ârelay failing to latch or overload tripping.
- Continuous humming with no start – âstart⢠windingâ not being⤠engaged orâ relay âcontacts welded.
- Compressor starts when ânudged but not â¤automatically – intermittent relay âor weak start assist.
- Burnt plastic âodor, discoloration,⢠or visible⢠charring on the relay/overload⤠housing – thermal âfailure or arcing.
- Tripped âbreakers or large⣠voltage drops on startup – high â˘inrush current due to a âfailedâ start circuit.
Diagnosing the assembly combines visual â˘inspection and⤠electrical⣠tests: with âpower âŁremoved,â check⤠for burned terminals, crushed or loose connectorsand for an âopen â¤circuitâ across the overload⢠or âŁrelayâ terminals withâ a multimeter. âOn a powered live testâ (performed byâ trained technicians âusing appropriate safety precautions), a clamp ammeterâ at the compressor supply will show a normal inrush spike⤠then settle to running current; an absent spike or persistent high current indicates start-circuit or motor⤠winding issues. Practical replacement guidance: if the relayâ shows open/inconsistentâ continuity, the overload tripsâ at currents below⤠the compressor’s rated run â˘currentor⤠there is evidence of overheating,â replace the start âkit rather than attempting field â˘repairsand âverify model âŁcompatibilityâ with â¤the applianceâ model number âŁbefore⣠installation.
| Item | Description |
|---|---|
| Visual indicators | Discoloration, âmelted⣠housing,⤠or loose terminals suggest thermal⣠or arcing failure. |
| Multimeter check | Open circuit â˘on relay⢠orâ overload underâ bench test â¤indicates replacement; intermittent continuity indicates âŁimminent failure. |
Compatibility, â˘Replacement âConsiderationsand Installation Procedures âŁfor Field âService⣠Technicians
The 4387535 âŁWhirlpool Refrigerator Compressor Relay And Overload Start⤠Kit combinesâ a start relay (or PTC/current-type starting âdevice) with a thermal overload protector âŁto control âandâ protect the âcompressor âŁduring âstartup and short-term fault conditions. The relay momentarilyâ connects âthe start âwinding to âcreate âthe necessary⣠phase âshift and⣠torque; â˘the overload senses excessive current or â˘temperature â˘and opens the circuit toâ prevent âwinding damage. â˘For compatibility, match the kit to the compressor’s âterminalâ layout⣠(commonly labeled S, R, C), rated locked-rotor current⤠and âŁnominal supply voltageand the physical⤠mounting or⢠snap-in interface so the⤠relay establishesâ reliable⢠contact and⢠the overload maintains thermal coupling to the compressor⣠housing.
- Compatibility checks: terminal âlabelsâ and pin spacing, rated amperage/voltage,â and âŁmechanical fit withâ the compressor casing.
- Common symptoms indicating replacement: repeated humming without âstart,⤠high starting currentâ measuredâ at the mains, intermittent startsor an âoverload that trips frequently.
- Practical off-compressor checks: â˘measure coil resistance and continuityand⢠verify theâ overloadâ opens at elevated âtemperature in bench testing if âsafe and equipped to âdo â˘so.
Field technicians replacing⣠the kit should follow a concise procedure: disconnect power, remove the rear access⣠panel,⤠photograph⤠and label wire positions, remove the old⤠relay/overload assemblyand install the⤠replacement⣠ensuring âŁfirm terminal â¤connectionsâ and â¤preservation of any insulating sleeves. After â˘reassembly, Energizeâ the unit and measure â¤starting currentâ andâ run currentâ with⣠a clamp⢠metre; aâ properly functioning relay will reduce start â˘time andâ theâ overload should remain â¤closed duringâ normal operation but âopenâ under sustained overload conditions.When inâ doubt,cross-reference compressor model â˘numbers and service literature ratherâ than relying solely on visual similarities,because similar-lookingâ relays â¤can differ in electricalâ ratings⢠and thermal characteristics.
| Item | Description |
|---|---|
| Part | 4387535 Whirlpool Refrigerator⢠Compressor Relay And Overload Start⢠Kit |
| Function | Provides start âŁassist to compressor and thermal âprotection⣠against overcurrent/overtemperature |
| Terminals | Typically â¤S, âR,⢠C – confirm pinâ layout and⣠spacing before replacement |
| Typical checks | Continuity of relay â˘coil, open/close behavior of overloadand âstarting current measurement |
Q&A
what is â˘the 4387535 Whirlpool compressor relay and âŁoverloadâ start âkit?
The 4387535 (frequently enough listed as âŁWP4387535) is a start kit⢠that includes aâ start relay and an overload/protector designedâ for⤠certain âWhirlpool-brand â˘compressors.Theâ start relay momentarily provides âextra current â¤toâ the compressor start winding to âget âthe motor going;⤠the overload protects the compressor from overheatingâ or âdrawing excessiveâ current.
Which refrigerator models⣠will âthis kit fit?
It âfits select Whirlpool, KitchenAid, âŁMaytag, Amana and someâ Kenmore â¤refrigerators that use â˘the compatible compressor âstyle. Compatibility depends⢠onâ the refrigerator model and compressor electrical terminal arrangement, so⣠always verify the part number against yoru applianceâ model⢠or consult the manufacturer âparts â˘list before ordering.
What symptoms indicate the relay/overload kit is bad?
common signs include âthe compressor trying to start (clicking) âbut not⤠running, a humming noise⣠from the compressor,⤠intermittent coolingâ or âŁthe fridge being warm â¤while⣠the compressor is hot, frequent breaker trips, âandâ visual âŁsigns of damage âŁ(burn marks, melted â˘plastic)â on the relay/overload. A ârattling sound âinside the relay⢠when⣠shaken can also indicate internal failure.
Can I testâ the relay and overload myself,â and how?
Basic âŁnon-live âchecks you can do: visually inspect âforâ burns or melted parts, listen for⣠clickingand perform a shake test (a loose rattle can indicate failure). With the âunit unplugged â˘you can use âa âŁmultimeter to checkâ for continuity across terminals â(continuity alone doesn’t âguarantee â˘a good⣠start device⣠but a complete open circuit⣠indicates failure). âŁAvoid applying live âpowerâ to components âunless you are trained; for powered tests or in-depth diagnosis, contact a qualified appliance technician.
Is it difficult to replace the 4387535 kit âŁ-â can a homeowner do it?
On many refrigerators⢠replacing the start⢠relay/overload⣠is âa straightforward task â¤usually involving unplugging the appliance, accessing the compressor at â¤the back, unplugging the old âkit and plugging in the new one. Though, âŁit requires basic safety precautions (disconnectâ power,â avoid bending compressor lines) and⢠correct terminal fit. If âyou are not pleasant working on⤠appliances or cannot access⤠the compressor safely, hire a qualified technician.
If I âreplace the relay/overload and⢠the fridge⢠still âdoesn’t cool, what doesâ that âmean?
Replacing the⤠start kit⢠fixes starting/electricalâ protection issues but willâ not repair sealed-system problems (refrigerant âleaks, a âmechanically locked or âinternally failed âcompressor). If the⣠compressor is receiving power but won’t runâ or draws excessive⤠currentor âif there are âsigns⤠of a refrigerant leak, the compressor or sealed â˘system âŁlikely needs professional repair or replacement.
Are there⣠aftermarketâ alternatives andâ should I⤠choose OEM?
Aftermarket start kits are available and can âbe less expensive.â For âreliability choose â˘reputable â¤brands with correct âŁelectrical and âmechanical specifications and a warranty.OEM parts⤠(WP4387535) are âŁgenerally recommended when âavailable because they are guaranteed to âmatch the⤠original terminal layout and thermal characteristics.
Any tips to⣠prevent prematureâ failure of the relay/overload?
Keep condenser âcoils clean âand ensure proper ventilation aroundâ the refrigerator âtoâ reduce compressor stress. â¤Avoid frequent power cycling or movingâ the fridge while it’s running.Promptly address intermittent starting issuesâ rather⤠than repeatedly restarting the appliance, â˘and âhave âhigh-current⣠or overheating problems inspected by â¤a technician⢠to prevent repeated relay/overload failures.
Toâ conclude
The 4387535 Whirlpool Refrigerator Compressor Relay And Overload Start⢠Kitâ plays a focused⤠but criticalâ role in ârefrigerator â¤operation by â¤enabling reliable compressor âŁstartup and⣠providing protection against electricalâ overload and overheating.As a combined relay and overload device, it helps ensure theâ compressor engages when required, contributes⤠to â˘stable cooling performance, â¤and⣠reduces the risk of damageâ from ârepeated hard â˘starts â¤or electrical⢠faults.
Proper⤠diagnosis âand âŁtimelyâ replacement of the 4387535⣠Whirlpool⣠Refrigerator âCompressor Relay And Overload Start Kit areâ notableâ to âavoid needless repairs and toâ protect âŁthe compressor fromâ long-term damage. Symptomsâ such as failure âto start, persistent humming, rapid âŁon/off cyclingor a âwarm interior warrant testing by a trained⣠technician; confirming the relay and overloadâ condition beforeâ replacement ensures the correctâ remedy⣠and avoids replacing parts â¤that are not âthe root cause.
When replacement isâ necessary, selecting â˘the correct, compatible kit and⤠arranging professional installation help restore reliable operation,⢠improve energy âefficiencyand extend theâ service life of the appliance.Routine inspection âŁand prompt âŁattention to â˘starting or electrical⢠issues â˘support consistent cooling performance andâ reduce the âlikelihood of âmore extensive, costly failures.
Professional Appliance Service
If your appliance requires professional diagnosis or repair, visit
Revolff Home Services
for expert appliance repair services.
For local appliance service information see
Dryer repair Henderson
.
Replacement parts for many appliance models can also be found at
Reliable-Parts-Hub
.
Recommended Products
