Ice Maker Not Making Ice: What a Technician Tests, Brand by Brand

A refrigerator ice maker needs four things to make a cube: a cold enough mold, water that reaches it, a module that decides when to harvest, and a signal that the bin is not already full. When the bin stays empty, one of those four has stopped, and the symptoms often look the same from the front of the refrigerator. A technician separates them in a fixed order, starting outside the machine and ending at the control. Below is that order with the readings we look for, brand by brand. The tests assume you have worked on 120-volt circuits that sit next to water lines before.

This page is about ice makers inside residential refrigerators: freezer-mounted units and the in-door ice makers on French-door models. Freestanding and commercial ice machines from Hoshizaki, Manitowoc, Scotsman and Ice-O-Matic are a different machine, covered on ice machine repair. If the ice maker works but the cubes come out small or hollow, go to hollow and small ice cubes.

What a technician brings to this call

• A digital multimeter rated CAT III and a non-contact voltage tester.
• A freezer thermometer and an infrared thermometer for the mold and the fill tube.
• A measuring cup and a timer for a fill-volume test, and a pressure gauge that threads onto the supply line.
• An insulated jumper for the test points on Whirlpool-style modules, and a steamer or hair dryer for thawing a frozen fill tube.
• The tech sheet, which gives the valve coil resistance, the module test procedure and the error codes for that model.

Step 1: freezer temperature comes first

An ice maker will not harvest until its mold is cold enough. Whirlpool-style modular ice makers, which Whirlpool, Maytag, KitchenAid, Kenmore and many GE and Frigidaire models use in some form, start a harvest when a thermostat on the mold reaches roughly 15°F. A freezer that holds 10°F or warmer will make ice slowly, or the cubes will be soft in the middle, or the mold never gets cold enough to start a cycle at all.

The technician reads the freezer with a thermometer between packages after the door has been closed a while. The target is about 0°F. If the freezer is warm, the ice maker is not the problem, and the call becomes a cooling call. That diagnosis is on refrigerator not cooling.

In-door ice makers on French-door refrigerators add a step. The ice compartment in the door is cooled by air ducted from the freezer through a small fan, or by its own small evaporator on some Samsung models. If that fan stops or the duct ices shut, the freezer can sit at 0°F while the door ice compartment runs far too warm to freeze anything.

Step 2: is water reaching the mold?

A technician removes the bin, looks at the mold, and starts with the outside of the machine.

• The supply valve at the wall or under the sink must be fully open. Saddle valves that pierce a copper line clog with mineral scale over time and pass only a trickle.
• Pressure matters more than people expect. Most refrigerator inlet valves are rated for roughly 20 to 120 psi, and many makers ask for 35 psi or more when a water filter is installed. Reverse osmosis systems and homes on low municipal pressure can fall below that, and the valve then fills too little in its timed window.
• A water filter past its date restricts flow. Makers generally call for replacement about every six months, and Miami water’s mineral content shortens that.
• If the door dispenser delivers water at a normal rate, the supply, filter and the dispenser side of the valve are working. That narrows the fault to the ice maker side of the valve, the fill tube or the module.

Then the fill-volume test. The technician triggers a fill, collects the water that comes out of the fill tube in a cup, and compares the volume to the specification on the tech sheet. Too little water makes small or hollow cubes. No water at all, with the module calling for it, points to the valve, a frozen fill tube, or a module that is not sending power.

Step 3: the inlet valve, live and dead

The inlet valve is a solenoid on the back of the refrigerator, at the bottom. Most have two or more coils: one for the ice maker, one for the dispenser.

The valve’s inlet screen catches sediment from the supply line. In South Florida that screen collects scale, and a partly blocked screen gives a valve that tests fine electrically and still underfills. A valve that weeps when it is supposed to be closed causes a different problem: water drips into the fill tube between cycles and freezes there, and eventually the tube is a solid plug of ice.

Step 4: the frozen fill tube

The fill tube carries water from the valve through the back wall of the freezer into the mold. It passes through freezing air on the way, so any water that sits in it freezes. A tube that freezes solid blocks every fill after that, and the ice maker keeps cycling with an empty mold.

The cause of the freeze matters more than the ice. The common ones:

• Low water pressure, so the fill trickles slowly and freezes in the tube before it reaches the mold.
• A valve that weeps between fills.
• A failed fill tube heater on models that have one, including many Samsung and LG in-door ice makers.
• Warm, humid air leaking into the ice compartment on French-door models, frosting the fill tube and the tray. On some Samsung French-door refrigerators this frost also locks the auger and ices the fridge evaporator behind it.

Thawing the tube with warm air brings the ice maker back for days or weeks. If the cause is not found and fixed, the tube freezes again.

Step 5: the module, the shutoff and the test cycle

The module is the motor, timing gear, thermostat or sensor and heater that run the harvest. It decides when the mold is frozen, warms the mold to release the cubes, sweeps them out, and calls for the next fill. It also stops when the bin is full, read by a wire arm, a paddle, or an infrared optic depending on the design.

The test cycle tells you which half failed. If the module harvests and calls for water, and no water arrives, the fault is in the valve or the fill path. If the module does not move at all with the mold cold and the shutoff in the on position, the module itself is the suspect, or the board feeding it. A module that harvests but leaves cubes stuck in the mold usually has a failed mold heater.

Step 6: the ice compartment, the fan and the seals

On French-door refrigerators with in-door ice, the ice compartment is a small insulated box cooled by air ducted from the freezer. A technician checks three things there. The ice fan has to run when the ice maker calls for cooling; on LG an Er IF code points here. The compartment gasket has to seal against the door liner, because a gap lets warm fresh-food air in, frost builds on the tray, and the ice maker eventually jams. And the duct from the freezer has to be clear of ice.

On some Samsung French-door models a known leak path lets humid air into the ice room. Chipping the ice out works for a short time. The lasting repair is the manufacturer’s seal, drain and fill-tube kit, sometimes with a new auger motor.

Reassembly and the test that confirms it

• The water line at the valve is checked for drips with the supply on before the rear cover goes back.
• The fill tube is seated so that it points into the fill cup of the mold, not at the edge, where water freezes on the outside and builds a ledge.
• Compartment gaskets and covers are reseated on French-door models, with the ice fan confirmed running.
• The confirming test is a forced harvest and fill, with the fill volume measured, followed by a few hours of normal production and a check that the next harvest happens on its own.

What our technician does on a no-ice call, and what it costs

Freezer temperature, supply and pressure, filter, fill volume, voltage and resistance at the inlet valve, the fill tube, a forced test cycle on the module, then the ice compartment fan and seals on in-door units. Typical South Florida prices with parts and labor, from our current price pages:

• Inlet valve or fill tube: $140 to $310
• Whirlpool-style modular ice maker: $220 to $400
• In-door ice maker assembly: $260 to $460
• Optic board: $180 to $320
• LG ice fan: $180 to $320
• Samsung ice room seal, drain and fill-tube kit: $220 to $380, or $300 to $480 with a new auger motor

Most residential ice maker repairs fall between $180 and $460. We repair every refrigerator brand across Miami-Dade, Broward and Palm Beach, seven days a week. The service call is $59 and it is credited to the repair when you go ahead. Call (754) 345-4515, or see ice maker repair and refrigerator repair. Brand pages: Samsung ice maker, LG ice maker, Whirlpool ice maker. If ice is made but the dispenser will not push it out on a KitchenAid, read KitchenAid French-door slow ice and the auger motor.

Questions owners ask