--- title: "Find and check the water supply valve that feeds the ice maker" description: "Under the sink, behind the unit or below the floor; quarter-turn, multi-turn or saddle; fully open and dry at both ends, and closed in seconds when water…" url: "https://icemakerrepair.center/guides/find-and-check-the-water-supply-valve/" date_modified: "2026-09-26" --- Troubleshooting # Find and check the water supply valve that feeds the ice maker The water supply valve for an ice maker is usually under the kitchen sink, behind or beside the unit, or on a pipe in the basement or crawl space. Find it before you need it, learn which way closes it, and check that it is fully open, not a self-piercing saddle valve, and dry at both ends of the line. By [IceMakerRepair.center technical team](https://icemakerrepair.center/authors/technical-team/) Published September 26, 2026 ## At a glance. Somewhere between the house plumbing and the ice maker there is a small shut-off valve, and most owners have never seen it. Finding it on a calm day matters for two reasons: a half-closed valve starves the ice maker, and in a leak it is the one thing you need to close within a minute. Read the whole guide ### Where GE says to look Behind the unit, under the sink, basement or crawl space A built-in may have it behind the kickplate, which Sub-Zero allows as long as it can be reached. ### Valve to avoid A self-piercing saddle valve GE, Whirlpool and Sub-Zero all say it does not supply enough flow. ### Supply tubing makers specify 1/4-inch outside-diameter soft copper or PEX Whirlpool's figure, with a loose loop behind the unit so it can be pulled out. ### In a leak Close the valve first, power second Switch the breaker off only from a dry panel away from the water. In this guide 1. Where the valve usually is 2. Which kind of valve you have 3. Checking that it is fully open and dry 4. Closing it fast when water is on the floor 5. Old valves that stick, drip or snap 6. Step by step 7. Questions ## Where the valve usually is GE lists the usual places as behind the unit, under the sink, or in the basement or crawl space, and it notes that only one supply line runs to the unit's inlet valve. That single line is your guide: follow it back from the unit, and the first valve you reach on it is the one you want. Open the cabinet under the sink before moving anything heavy, since that is where most kitchen installers put it. ### Under the kitchen sink Look at the cold-water stop that feeds the faucet. An ice maker line is often teed off it with a second small valve, or runs from a separate stop beside it, and the thin copper or plastic tube heads off through the cabinet wall toward the unit. If there are two small tubes, the one that runs toward the unit rather than up to the faucet is the ice maker's. ### Behind or beside the unit Many installations put a small valve in a recessed box in the wall behind the unit, which means sliding a freestanding model out to reach it. For built-ins and panel-ready units, Sub-Zero says the plumber-supplied valve is usually about 6 inches from the compression fitting and may sit behind the kickplate, as long as it stays accessible. Undercounter ice makers often have it in the next cabinet over. ### Below the floor Where the kitchen sits over a basement or crawl space, the line often drops through the floor near the back wall and joins a cold pipe below. Look directly under the unit's position for a thin tube running along a joist. Label the valve with a tag once you find it, so the next person does not have to search. Source: [GE Appliances — Icemaker does not fill with water](https://products.geappliances.com/appliance/gea-support-search-content?contentId=17408) — The shut-off valve is usually behind the unit, under the sink, or in the basement or crawl space; only one supply line goes to the water valve ## Which kind of valve you have The type decides how to close it and how much you can trust it. Look at the handle and at how the valve is attached to the pipe before you turn anything. - Quarter-turn valve with a lever handle: open when the lever lines up with the pipe, closed when it sits across it. - Multi-turn stop with a round or oval handle: clockwise closes it, and it takes several full turns in either direction. - Saddle valve clamped around the outside of a copper pipe with a small T-handle: it pierces the pipe, and GE, Whirlpool and Sub-Zero all advise against it because the opening is too small. - No valve at all on the line: have one added; Sub-Zero calls for an easily accessible shut-off on every connection. Source: [Sub-Zero — Water line saddle valve](https://www.subzero-wolf.com/assistance/answers/sub-zero/common/water-line-saddle-valve) — Do not use self-piercing valves; the shut-off is usually about 6 inches from the compression fitting and may sit behind the kickplate if accessible; the supply needs an easily accessible shut-off; [GE Appliances — Self-tapping water valve](https://products.geappliances.com/appliance/gea-support-search-content?contentId=18959) — Saddle valves are not recommended because the opening is too small; restricted flow gives small, slow and hollow cubes; [Whirlpool — How to check the water supply line](https://producthelp.whirlpool.com/Refrigeration/Full-Size_Refrigerators/Product_Info/Installation_Support/How_to_Check_the_Water_Supply_Line) — Use a 1/4-inch valve that needs a drilled hole, not a piercing or 3/16-inch saddle valve; 1/4-inch O.D. copper or PEX; check for kinks and at the valve and back-of-unit connections Close on a quarter-turn shutoff valve with its handle parallel to a braided water line on a wall. ## Checking that it is fully open and dry Samsung and Whirlpool both start low-flow troubleshooting by making sure this valve is fully open. A water supply valve that was closed for other plumbing work and reopened only a turn or two passes enough water for the dispenser to seem fine and not enough for the ice maker's short timed fill. Open a quarter-turn valve until the lever is in line with the pipe; open a multi-turn valve counterclockwise until it stops, then back it off a quarter turn so it does not stick. Then check both ends with a dry paper towel. Whirlpool asks owners to check the connection at the supply valve and where the tubing joins the back of the unit, and to make sure the line has no kinks, which often appear after a unit is pushed back too far. A towel that comes away damp, green or white crust on a fitting, or a tube pressed flat against the wall are all reasons to call a technician rather than tighten things harder. Source: [Whirlpool — How to check the water supply line](https://producthelp.whirlpool.com/Refrigeration/Full-Size_Refrigerators/Product_Info/Installation_Support/How_to_Check_the_Water_Supply_Line) — Use a 1/4-inch valve that needs a drilled hole, not a piercing or 3/16-inch saddle valve; 1/4-inch O.D. copper or PEX; check for kinks and at the valve and back-of-unit connections; [Whirlpool — Ensuring correct water pressure](https://producthelp.whirlpool.com/Refrigeration/Full-Size_Refrigerators/Product_Info/Tips_and_Tricks/Ensuring_Correct_Water_Pressure) — Ensure the water shutoff valve is fully open; check for kinks after the unit was moved; [Samsung — Ice maker is not working](https://www.samsung.com/us/support/troubleshoot/TSG10002387/) — Make sure the home's water supply valve is fully open ## Closing it fast when water is on the floor In a leak, the order matters. Turn the valve off first; that stops the water in seconds, and everything else can then wait. Do not reach behind a wet unit or into a flooded sink cabinet toward an outlet or power strip to unplug anything. If power needs to be cut, do it at the breaker, and only when the panel is dry and away from the water. If the valve will not turn, or the leak is on the house side of it, close the main shut-off for the house, usually where the water line enters the building or near the water heater. Once the water has stopped, dry what you can and leave the line off until it has been repaired. - Valve closed: clockwise on a round handle, lever across the pipe on a quarter-turn. - Hands and feet out of the water around any plug, power strip or floor outlet. - Breaker switched off only from a dry spot, if the unit or an outlet is wet. - House main closed if the small valve will not move or the leak is on the pipe side of it. ## Old valves that stick, drip or snap A multi-turn stop that has sat open for a decade often seizes with mineral buildup. Forcing it with pliers can snap the stem or loosen the packing nut behind the handle, which then drips. If a valve will not move with firm hand pressure, leave it open and have it replaced rather than fighting it on the day you need it. Saddle valves age worse than any other kind. The rubber seal under the clamp hardens and the pierced pipe corrodes around the hole, and GE notes that the restricted flow they give is linked to small, slow and hollow ice. Whirlpool's recommended alternative is a 1/4-inch valve fitted into a drilled hole, and replacing one is a small job for a plumber that often improves the ice as well. Source: [GE Appliances — Self-tapping water valve](https://products.geappliances.com/appliance/gea-support-search-content?contentId=18959) — Saddle valves are not recommended because the opening is too small; restricted flow gives small, slow and hollow cubes; [Whirlpool — How to check the water supply line](https://producthelp.whirlpool.com/Refrigeration/Full-Size_Refrigerators/Product_Info/Installation_Support/How_to_Check_the_Water_Supply_Line) — Use a 1/4-inch valve that needs a drilled hole, not a piercing or 3/16-inch saddle valve; 1/4-inch O.D. copper or PEX; check for kinks and at the valve and back-of-unit connections ## Where to stop Stop if the valve will not turn by hand, if a fitting is wet or crusted, if you find a saddle valve, or if the line runs through a wall or floor you would have to open. Close the valve if anything is dripping. Water near an outlet or power strip means staying clear of it and switching the breaker off only from a dry panel; pulling a heavy built-in or panel-ready unit out of its opening is a job for a technician. Written by [IceMakerRepair.center technical team](https://icemakerrepair.center/authors/technical-team/). The technicians sent out when an ice maker visit is booked on this site. They write from what they find at the supply valve, along the fill tube, in the ice bin and at the drain, and they check it against the maker's own manuals wherever one is published. Sources: [GE Appliances — Icemaker does not fill with water](https://products.geappliances.com/appliance/gea-support-search-content?contentId=17408) · [Sub-Zero — Water line saddle valve](https://www.subzero-wolf.com/assistance/answers/sub-zero/common/water-line-saddle-valve) · [GE Appliances — Self-tapping water valve](https://products.geappliances.com/appliance/gea-support-search-content?contentId=18959) · [Whirlpool — How to check the water supply line](https://producthelp.whirlpool.com/Refrigeration/Full-Size_Refrigerators/Product_Info/Installation_Support/How_to_Check_the_Water_Supply_Line) · [Whirlpool — Ensuring correct water pressure](https://producthelp.whirlpool.com/Refrigeration/Full-Size_Refrigerators/Product_Info/Tips_and_Tricks/Ensuring_Correct_Water_Pressure) · [Samsung — Ice maker is not working](https://www.samsung.com/us/support/troubleshoot/TSG10002387/) ## Step by step. Four steps, in the order worth doing them. 01 ### Follow the line Trace the thin supply tube from the back of the unit to the first valve on it, starting under the sink. 02 ### Identify the type Note whether it is a quarter-turn, multi-turn or saddle valve, and which way closes it. 03 ### Open it fully Open it all the way, backing a multi-turn valve off a quarter turn from the stop. 04 ### Check both ends Run a dry paper towel around the fittings at the valve and at the back of the unit, and look for kinks between them. For the heart of your home. ## Questions owners ask. ### Is it normal for the ice maker line to share a valve with the kitchen faucet? Many installations tee off the sink's cold stop. It works, but it means closing that stop also cuts the faucet, and a separate small valve on the branch makes it easier to isolate the ice maker alone. ### Should the valve be left fully open all the time? Yes, while the ice maker is in use. A partly open valve does not save water; it only makes the fill short. The exception is a long absence, when closing it removes the chance of a leak nobody is there to see. ### The line behind the unit is thin clear plastic. Is that acceptable? Whirlpool specifies soft copper or PEX of 1/4-inch outside diameter. Thin clear tubing is easily kinked and ages quickly, and a braided or PEX line is usually worth having fitted the next time the unit is pulled out. ## The problems behind it. Each has a page of its own: what it usually means and the causes in the order worth checking. [All 17 problems](https://icemakerrepair.center/problems/) Water on the floor or near power ### Ice Maker Water Line Leaking Behind the Cabinet 6 causes, cheapest first Water on the floor or near power ### Ice Maker Leaking on the Floor 6 causes, cheapest first Problem ### Ice Maker Making Small or Hollow Cubes 6 causes, cheapest first Problem ### No Ice Coming From the Ice Maker 7 causes, cheapest first ## When it needs a technician. The repairs on the right are where this guide ends when the checks do not settle it. ### Water filter and supply line service The filter, the shutoff valve and the thin line that bring water to the ice maker, checked for flow, leaks and age, with a worn line or saddle valve replaced and a new filter seated properly. ### Ice maker water inlet valve repair The electric valve that lets water into the ice maker, tested and replaced when it will not open, opens only partway, or keeps dripping after it should have closed. ### Diagnostic visit A visit that traces the water from the supply valve to the bin and back out through the drain, and names the one part that stopped the ice before anything is ordered. ## More in troubleshooting. The checks an owner can make on an ice maker without taking a risk, from finding the water valve and testing the fill to thawing a frozen fill tube, and the point where it is time to stop and book. [The whole section](https://icemakerrepair.center/guides/troubleshooting/) Ice maker checks an owner can safely make ### How to reset and test an ice maker, and read what the cycle shows Test buttons, power cycles and the wire arm, what a healthy cycle looks and sounds like, a hand-fill check for models with no button, and why pressing test twice floods the mold. Ice maker checks an owner can safely make ### Thaw a frozen fill tube safely, then stop it freezing again Telling a blocked tube from a dead valve, the power-off thaw that adds no heat, the shortcuts that crack plastic and wet wiring, and the slow fill that freezes it again. Guides ### All 18 guides Six sections, by what you are trying to find out. --- **[Read on the site: Find and check the water supply valve that feeds the ice maker](https://icemakerrepair.center/guides/find-and-check-the-water-supply-valve/)** **[Book a visit with IceMakerRepair.center](https://icemakerrepair.center/schedule/)**