Igniter
Price the ignition part only after confirming the model number and connector.
Bradford White water heaters with an Icon System control display error codes as a series of LED flashes. Error code 1 (one slow flash) means pilot outage — the pilot light went out or failed to establish during ignition.
No hot water. The fix is usually a $10–$25 thermocouple or thermopile, not a new water heater.
Jump to Fix
- What Error Code 1 Means
- Most Common Causes
- Step-by-Step Diagnosis
- How to Relight the Pilot
- Parts and Costs
- When to Call a Tech
What Error Code 1 Means
The Icon System control on Bradford White gas water heaters flashes the status LED to communicate fault codes:
- 1 slow flash (every 3 seconds) = Pilot outage / no pilot signal
The control tried to sense the pilot flame and got no signal. This means either:
- The pilot is not lit
- The pilot lit but the thermocouple or thermopile isn’t generating enough voltage to tell the control
- The gas valve isn’t opening the pilot circuit
Models affected: Any Bradford White gas water heater with the Icon System control — typically units manufactured 2005 to present, including the Defender Safety System (DSI) and FVIR compliant models.
Most Common Causes
| Cause | How common | Fix |
|---|---|---|
| Pilot went out (draft, gas interruption) | Very common | Relight per instructions on heater label |
| Thermocouple failed or loose | Very common | Replace thermocouple ($8–$25) |
| Thermopile failed (low millivolt output) | Common | Replace thermopile ($20–$55) |
| Pilot orifice clogged | Occasional | Clean pilot assembly |
| Gas supply interrupted | Occasional | Check meter, shutoff valve, other appliances |
| Gas valve failure | Uncommon | Replace gas valve ($90–$200) |
Start with the simplest fix: relight the pilot. If it relights and holds, no parts needed. If it relights but the error returns within minutes, the thermocouple or thermopile is failing.
Step-by-Step Diagnosis
Step 1: Check the pilot
Look through the sight glass at the bottom of the water heater (or follow the relight instructions on the label). Is the pilot flame visible?
- No flame visible: Go to Step 2 (relight)
- Flame visible but error persists: The thermocouple/thermopile isn’t reading the flame — go to Step 3
Step 2: Relight the pilot
Follow the relighting steps on the data plate (usually on the front of the heater). General procedure:
- Turn the gas control knob to OFF
- Wait 5 minutes to clear any accumulated gas
- Turn the knob to PILOT
- Press and hold the pilot button (or knob), then press the igniter button repeatedly until the pilot lights
- Continue holding the pilot button for 30–60 seconds after the pilot lights
- Release slowly — the pilot should stay lit
- Turn the knob to your desired temperature setting
If the pilot lights and holds, the error code should clear. If it goes out again within minutes, go to Step 3.
Step 3: Test the thermocouple voltage
A healthy thermocouple generates 25–30 millivolts when in a pilot flame. A failing one generates under 15 mV — not enough to hold the gas valve open.
To test:
- Use a multimeter set to DC millivolts
- Disconnect the thermocouple lead from the gas valve
- Relight the pilot and hold the button
- Touch the multimeter leads to the thermocouple tip and the connector
- Reading under 15 mV: Replace the thermocouple
- Reading 20+ mV but valve won’t stay open: Gas valve may be faulty
Step 4: Inspect the thermopile
Bradford White Defender Safety System models use a thermopile (two-wire) in addition to the thermocouple. The thermopile powers the Icon System control.
Normal thermopile output: 300–750 mV at operating temperature. Measure across the two thermopile wires at the gas valve:
- Under 200 mV: Thermopile is failing — replace it
- Over 300 mV but error persists: Check wiring connections at the control
How to Relight the Pilot
Full step-by-step with photos is on the Bradford White data plate. The Pilot Relight label is on the front of the heater. Follow it exactly — don’t skip the 5-minute gas purge wait.
If you smell gas at any point: Do not attempt to relight. Leave the area, don’t use any electrical switches, and call your gas utility.
Parts and Costs
| Part | Bradford White OEM # | Amazon equivalent | Cost |
|---|---|---|---|
| Thermocouple (standard) | 239-40336-00 | Universal 24” thermocouple | $8–$18 |
| Thermopile (Defender models) | 100-112568-07 | Honeywell Q340A1082 thermopile | $20–$55 |
| Gas valve (if valve fails test) | 239-48774-00 | Brand-specific, call Bradford White | $90–$200 |
| Pilot assembly (complete) | 239-41599-00 | Model-specific | $35–$80 |
Need Replacement Parts?
Before ordering, match the water-heating part to the model number, electrical rating, and failure symptom. Check current prices on Amazon - prices and availability change frequently.
Tool needed: A 7/16” wrench or adjustable pliers to disconnect and reconnect the thermocouple nut. The replacement takes about 15 minutes on most models.
The thermocouple unscrews from the gas valve body (clockwise to tighten, counterclockwise to remove). Route the new one the same way as the old one to keep it in the pilot flame path.
When to Call a Tech
Call a licensed plumber or water heater technician if:
- The pilot relights but immediately blows out (could be a draft, flue blockage, or gas pressure issue)
- You replaced the thermocouple and still get error code 1
- The gas valve tests indicate a failed valve (replacing a gas valve is a gas-licensed job in most states)
- You smell gas and can’t identify the source
- The water heater is over 12 years old (replacement may be the better investment)
Average repair cost with a technician: $150–$350 for thermocouple/thermopile replacement including parts and labor. Gas valve replacement: $300–$600 installed.
Related Bradford White Error Codes
- Error code 2 — Thermopile voltage low (thermocouple circuit under voltage but pilot flame present)
- Error code 4 — Ignition failure (electronic ignition models)
- Error code 7 — Bradford White error code 7 fix guide