mypros+
Error code reference

Bradford White Water Heater Error Code 1 short flash per second

Weak pilot signal detected on last call for heat.

Bradford White codesBradford White water heater codes

Weak pilot signal detected on last call for heat.

First step from the service manual

Inspect pilot assembly per Service Procedure II (page 17): check for unstable pilot, blocked/restricted pilot tube, oxidation on pilot electrode, or wire damage.

The complete diagnostic procedure includes additional test steps, resistance specifications, wiring diagram references, and component test points.

MyPros+ Max

Get the full diagnostic procedure for 1 short flash per second.

  • Step-by-step tests with expected resistance, voltage, and continuity values
  • Wiring diagram references and connector pinouts from the OEM service manual
  • Verified part numbers when replacement is required
Get the full procedure

$29/month · Cancel anytime · Or $9.95 3-day pass

What 1 short flash per second means on a Bradford White water heater

The 1 short flash per second status code on a Bradford White water heater indicates that a weak pilot signal was detected during the most recent call for heat. This signal is generated by the thermocouple or thermopile assembly, which produces a small millivolt output when the pilot flame heats the sensing element. When that output falls below the threshold required by the gas valve control module, the system logs this fault and may shut down the heating cycle to prevent unsafe operation.

The pilot signal can weaken for several interconnected reasons. A small, unstable, or improperly positioned pilot flame will not heat the sensing element sufficiently, reducing millivolt output. A blocked or restricted pilot tube limits gas flow to the pilot burner, producing exactly this kind of undersized flame. Oxidation or carbon buildup on the pilot electrode degrades electrical conductivity and the quality of the flame sense signal, even when the flame itself appears adequate.

Wire damage anywhere in the thermocouple or thermopile circuit is also a direct cause. Frayed insulation, corroded terminals, or loose connections introduce resistance that drops the signal voltage before it reaches the gas valve. Service Procedure II outlines a systematic inspection of the full pilot assembly including the tube, electrode condition, and associated wiring harness. Addressing the root cause is essential because resetting the unit without a repair will typically result in the fault recurring on the next call for heat.

Source: manufacturer service documentation.

Common causes of 1 short flash per second

  1. 01

    Blocked or restricted pilot tube

    Wiring / connection

    Debris, mineral deposits, or corrosion inside the pilot supply tube restricts gas flow, causing a weak or undersized pilot flame that cannot generate adequate millivolt output at the sensing element.

  2. 02

    Oxidation or contamination on the pilot electrode

    Wiring / connection

    Carbon buildup or surface oxidation on the pilot electrode reduces conductivity and degrades the flame sense signal. Inspect the electrode tip for discoloration or deposits and clean or replace as needed.

  3. 03

    Unstable pilot flame

    Wiring / connection

    Drafts, low gas pressure, or a partially obstructed pilot orifice can cause the flame to flicker or lift, producing an inconsistent signal that falls below the gas valve control threshold intermittently.

  4. 04

    Damaged or corroded wiring in the pilot circuit

    Wiring / connection

    Frayed insulation, corroded terminals, or loose connections between the thermocouple or thermopile and the gas valve add resistance to the circuit and reduce the effective signal voltage reaching the control.

  5. 05

    Worn or failed thermocouple or thermopile

    Part replacement

    After extended use, the sensing element degrades and produces insufficient millivolt output even when the pilot flame is properly sized and positioned. Replacement is required when output cannot be restored by cleaning or adjusting.

See the test procedure for each cause

Frequently asked questions about 1 short flash per second

What does 1 short flash per second mean on a Bradford White water heater?
This flash pattern indicates a weak pilot signal was detected during the last call for heat. The gas valve control monitors the millivolt output from the thermocouple or thermopile, and when that output is too low, it logs this fault. The most common causes are a restricted pilot tube, a contaminated electrode, or a degraded sensing element. The unit may shut down heating until the issue is resolved.
How do I fix the 1 short flash per second error on my Bradford White water heater?
Start by inspecting the pilot assembly following Service Procedure II: check for an unstable or undersized pilot flame, inspect the pilot tube for blockages or restrictions, clean any oxidation from the pilot electrode, and examine all wiring for damage or loose connections. If cleaning and inspection do not resolve the fault, the thermocouple or thermopile may need to be replaced. Always shut off gas supply before performing any internal inspection.
Is the 1 short flash per second error on a Bradford White water heater a safety concern?
Yes, this fault is a safety-related indication. The control system shuts down or limits operation when the pilot signal is too weak because it cannot reliably confirm that the pilot flame is present. Continuing to attempt operation without resolving the root cause could result in unburned gas accumulation. Address the underlying pilot assembly issue before returning the unit to normal service.
Will resetting the water heater clear the 1 short flash per second fault code?
Resetting the unit may temporarily clear the displayed fault, but the code will return on the next call for heat if the underlying cause has not been corrected. The control logs this fault because the pilot signal fell below acceptable levels during actual operation, so any reset without a repair is likely to be temporary. Inspect and service the pilot assembly before relying on the unit for normal hot water production.
How much does it cost to repair a Bradford White water heater showing 1 short flash per second?
If the repair only requires cleaning the pilot tube and electrode, costs are minimal and may involve only a service call fee, typically in the range of $75 to $150 depending on your area. If a thermocouple or thermopile replacement is needed, parts generally cost between $15 and $60, with total repair costs including labor ranging from $100 to $250. More extensive repairs involving the gas valve or wiring harness will fall at the higher end of that range.

Related Bradford White water heater codes

All Bradford White water heater codes
View all 98 Bradford White water heater codes

78,000+ service manuals · 160,000+ error codes · 55+ brands

Get Started

$29/month · Cancel anytime · Or $9.95 3-day pass