When a Jenn-Air refrigerator throws Error Code LO, it’s telling you the water supply is too low for the dispenser and/or ice maker. That doesn’t automatically mean something “broke.” Most of the time the fridge just isn’t getting enough water because of a simple restriction, a half-closed valve, a kinked line, or a clogged filter.
What “LO” Actually Means
The control expects a certain flow rate during a fill. If water arrives too slowly—or not at all—the board logs LO so the dispenser pump and ice maker don’t run dry. Before the code appears you’ll often notice a weak, sputtering stream at the dispenser, tiny or hollow ice cubes, or longer-than-normal filling sounds that end with nothing.
The Real-World Causes
In everyday kitchens, LO usually traces back to one of four things. The shutoff valve behind the fridge isn’t fully open, or it’s the old “saddle” style that’s partially clogged. The water line got pinched when the refrigerator was pushed back into the cabinet. The water filter is overdue or not clicked in all the way and is choking the flow. Or your home’s water pressure is simply low—common in multi-story buildings or homes on RO systems without a pressurized storage tank.
Less common, but worth mentioning: the ice maker’s small fill tube can freeze in a cold spot and mimic low supply, and a failing inlet valve can open weakly even when water pressure is fine.
Quick Wins Before You Grab Tools
Start simple. Pull the unit forward just enough to see behind it and make sure the supply line isn’t kinked. Open the shutoff valve fully. Reseat the water filter so it sits flush and locked, then run the dispenser for a couple of minutes to purge air. After that, power the fridge off for 5–10 minutes and turn it back on so the control can recheck flow with a clean slate.
If the stream is strong and the code doesn’t return, you’re done.
DIY Fixes That Actually Work
If LO comes back, work through these in order—slow and steady beats guesswork.
Swap the filter if you’re anywhere near the six-month mark or noticed taste/flow dropping. Use the correct OEM or certified compatible cartridge. After installing, purge a few full glasses to clear air and carbon fines.
Evaluate the shutoff valve next. Old saddle valves clog internally and act like a bottleneck. If you disconnect the line and crack the valve into a bucket but only get a weak trickle, replace it with a modern ¼-turn ball valve. It’s a small plumbing upgrade that solves a lot of LO complaints.
Check pressure if the valve flows well but the fridge still doesn’t. A cheap gauge on a cold faucet will tell you the truth. Aim for 50–80 psi. If you’re feeding the fridge from reverse osmosis, make sure that RO system includes a pressurized tank—or a booster—so the line can deliver a steady surge when the dispenser or ice maker calls for water.
Rule out a frozen fill tube when the dispenser is fine but ice production is poor. Power the fridge off and let that small tube thaw naturally, or gently warm the area with a hair dryer on low from a safe distance. Never poke the tube with tools; a pinhole becomes a leak later.
Consider the inlet valve if everything upstream checks out. A weak solenoid or a clogged internal screen can keep flow low even with good house pressure. If you’re comfortable, you can remove and rinse the tiny screens; otherwise, this is a good point to bring in a pro.
Clearing the Code (and Verifying the Fix)
Once flow is restored, the fridge typically clears LO on its own the next time it dispenses or fills the ice tray. Some models also allow a quick panel reset—check your use & care guide. A steady, non-sputtering stream and normal-sized ice within the next 12–24 hours are your green lights.
Keep LO from Coming Back
Short and sweet:
- Replace the water filter every 6 months (sooner with heavy use).
- Leave enough space so the fridge doesn’t pinch the line when you slide it back.
- Upgrade old saddle valves to a ¼-turn ball valve for full, reliable flow.
- Keep water pressure in the 50–80 psi range; add an RO tank/booster if you use reverse osmosis.
When to Call a Pro
If pressure is healthy, the filter is new, the line is straight, the valve is wide open, and LO still returns, the issue is likely the inlet valve or control-side logic—and that’s not worth guessing at. Visible leaks, repeated fill-tube icing at normal temperatures, or a humming valve that never fully opens are also signs to get help.