Faucet has no hot water cold flows — cold water flows

Use only checks that match the exact appliance or system and its official guide.

1. Check 1

   Run this faucet and one other nearby fixture that normally produces hot water, using each fixture's normal hot setting; compare temperature and flow without removing any parts.

   Expected result: Hot water is normal elsewhere, hot water is absent or weak at both fixtures, or the comparison fixture is not known to have a hot supply.

   Next step: For a local-only symptom, continue with the faucet supply checks. For a multi-fixture symptom, check only normal user-facing water-heater indicators and arrange water-heater or plumbing service rather than replacing a faucet part.

   Why this matters

   Why: Normal hot water elsewhere makes a local faucet, hot stop, or hot supply-line issue more likely. No hot water at multiple fixtures shifts suspicion to the water heater or upstream hot-water distribution.

2. Check 2

   Look under the sink or at the accessible faucet connections and identify the hot and cold supply stops; compare their visible positions and look for a sharply kinked, crushed, wet, or disconnected hot flexible line. Do not use pliers or a wrench on a stiff stop.

   Expected result: The hot stop is closed or partly open, the hot line is kinked or visibly damaged, a stop or connection is wet, or both stops and lines look normal.

   Next step: If the stop moves normally, follow the fixture's manufacturer instructions for its normal open position without forcing it and recheck flow. If it is stuck, leaking, or the line is damaged, leave the connection undisturbed and call a plumber.

   Why this matters

   Why: A closed stop or restricted line can remove hot flow while leaving cold flow normal. Wetness or a damaged line adds a leak risk. Normal visible supply conditions make a faucet-internal restriction more likely but do not prove it.

3. Check 3

   Move the faucet control through its normal range and briefly hold it at the full-hot position, then compare hot-side flow with the full-cold position; keep hands away from wet connections and do not remove the handle or cartridge.

   Expected result: Cold flow is strong but hot flow is absent, hot flow is only a weak trickle, or flow is normal but the water remains cold while another fixture has hot water.

   Next step: Record the pattern and faucet type. Do not pry out or clean an internal part based on appearance; use the exact model instructions or a plumber for cartridge, stem, or mixing-valve diagnosis.

   Why this matters

   Why: A cold-strong/hot-absent pattern supports a hot-side supply restriction or a faucet mixing assembly that is not opening. A weak hot trickle is consistent with partial restriction. Normal flow with cold temperature makes a mixing-control or upstream temperature issue more likely than a simple flow blockage.

4. Check 4

   Identify whether the faucet is single-handle, two-handle, or part of a pressure-balance or thermostatic control, and record the visible make, model, and any temperature-limit or cartridge markings without disassembling it.

   Expected result: The model and control type are known, or the model is unknown and the control has a specialized pressure-balancing or thermostatic design.

   Next step: Use the manufacturer's model-specific parts and service information or provide the identification to a plumber. If the model cannot be identified, do not order a cartridge by appearance alone.

   Why this matters

   Why: The internal cartridge, stem, spool, and temperature-control arrangement varies by model. A specialized control may restrict or mix the hot side differently from a basic two-handle faucet, so a generic replacement or cleaning assumption is unsafe.

5. Check 5

   If more than one fixture lacks hot water, inspect only the water heater's normal user-facing display, status light, or control indication and note any visible fault indication; do not open panels, adjust gas controls, or change electrical wiring.

   Expected result: The heater appears to have a normal status, shows a fault or no-power indication, or the water heater status is not accessible or not understood.

   Next step: Record the indicator exactly and arrange qualified water-heater or plumbing service. Keep the faucet diagnosis local only when another fixture confirms that hot water is available elsewhere.

   Why this matters

   Why: A visible fault or no-power indication with no hot water at multiple fixtures supports an upstream water-heater or distribution problem. A normal-looking indicator does not rule out a plumbing or heating fault.

6. Check 6

   Check the cabinet, faucet base, supply stops, and visible hot line for fresh moisture, staining, swelling, or water near an outlet or appliance; use a dry paper towel only for a non-contact location check.

   Expected result: The area is dry, or water is present at a stop, hose, fitting, faucet base, cabinet floor, or nearby electrical equipment.

   Next step: If a reliable local stop can be closed without force, leave the affected supply isolated; otherwise use the known main shutoff only if safe and call a plumber. Keep away from wet electrical equipment and do not operate it.

   Why this matters

   Why: A leak can restrict or interrupt the hot-side path and can cause property damage even when cold flow remains normal. Water near electrical equipment adds a shock hazard and is no longer a parts-selection problem.