Quick Answer:
An ice maker cycling can cause short, repeatable pressure drops in the home water system. These dips are usually demand-related: the ice maker draws water briefly and the system sees a small transient drop. Use simple isolation and observing tests to confirm whether the ice maker is the cause or whether something else—like a pressure regulator or a leak—is involved.
Why This Happens
Automatic ice makers use a solenoid valve that opens for a short time to fill the tray. That flow is usually small but happens in a concentrated pulse. If your supply pressure is marginal, that pulse can show as a measurable dip at faucets or in appliances. The same phenomenon appears with other timed or high-flow events; check related patterns such as Pressure unstable when sprinkler zone starts and Two showers running causes cold water loss for comparisons.
Step-by-Step What to Do
1. Confirm the pattern
- Note when the pressure dips happen: do they match the ice maker’s fill cycles (roughly every few hours or when making a batch)?
- Listen for the ice maker valve click and watch the appliance light or indicator to line up timing with the dip.
2. Test pressure with fixtures isolated
- Turn off or close valves to other fixtures and appliances so nothing else can draw water.
- Open a single faucet or attach a pressure gauge to an exterior hose bib or the closest usable outlet after shutting down other draws.
- Record the static pressure, then trigger an ice maker fill (leave it running or manually start a cycle if possible) and watch for the pressure change.
- If the dip occurs while other fixtures are isolated, the ice maker or supply piping to it is likely the cause.
3. Observe meter flow patterns
- Watch the water meter (analog sweep or digital flow readout) during a cycle. A short pulse on the meter timed with the dip confirms a demand event rather than a pressure regulator failure or leak.
- If you see repeated tiny pulses even with the ice maker off, investigate other intermittent devices or a leaking solenoid.
4. Confirm PRV setting
- Locate the pressure reducing valve (PRV) near the main shutoff or meter. Check the gauge reading at a hose bib to see if pressure is within normal range (typically 40–60 psi for many homes).
- If pressure is low to begin with, a PRV set too low can make small draws cause noticeable dips. Adjusting a PRV is possible but can affect the whole house—note the current setting before any change.
- If the PRV looks stuck or you are unsure how to adjust it safely, skip adjustments and call a pro.
5. Simple fixes and checks
- Check the ice maker’s feed line and its shutoff valve for partial blockage or a slow-closing solenoid.
- Replace a corroded or mineral-clogged inlet filter if present on the refrigerator feed.
- Re-test after any change to confirm improvement.
What Not to Do
- Do not assume a fixture has failed when the pattern is demand-related. Short, repeatable dips often mean normal draws, not a failing faucet or appliance.
- Do not tighten or replace the PRV without understanding house-wide effects—incorrect PRV settings can overpressurize plumbing.
- Do not cap or restrict the ice maker line as a long-term “fix” without diagnosing the root cause; you could create backflow or operational issues.
When to Call a Professional
- Persistent large pressure drops that affect multiple fixtures and do not line up with the ice maker cycle.
- If the PRV needs replacement or adjustment and you’re not comfortable doing it—PRV work often requires experience and the right tools.
- Suspected main-line leaks, meter problems, or complex issues in the service line where locating the source is difficult.
Safety Notes
- Turn off power to the refrigerator if you need to work on the water connection. Unplug before attempting any inspection inside the appliance.
- When working near the main, shut off the water and relieve pressure by opening a faucet before disconnecting lines.
- Avoid soldering or cutting supply lines yourself unless you are experienced—call a licensed plumber for any soldering or gas/electric appliance connections.
Common Homeowner Questions
- Why does the dip only last a few seconds?
A single ice maker fill is a short event; the system regains pressure quickly once the valve closes. - Can I disable the ice maker to stop the dips?
Yes—turning off the ice maker stops its water draws, but that masks the symptom rather than fixing low pressure or a restrictive feed line. - Will raising PRV pressure stop the dips?
Raising PRV pressure can reduce the size of dips, but it may create other problems if set too high; have a pro adjust it if you’re unsure.
For more related articles, see the Pressure Drops When Multiple Fixtures Run hub.