Error 1037 W

Safety first

1) Do not attempt any work on gas components or live wiring unless you are qualified. Isolate electrical power at the boiler isolator or the consumer unit before touching wiring or opening panels. Do not remove or alter any gas pipework. If your boiler is under warranty or service contract, contact Worcester Bosch or your installer.

Initial quick checks a homeowner can do

1) Try a simple reset: press and hold the reset button (or follow the panel reset procedure) for 3 seconds, then allow the boiler to restart. If 1037 clears and does not return, monitor for a day to ensure it doesn’t reappear.

2) Visually inspect the outside sensor cable where it enters the boiler and along any visible run outside. Look for cut, crushed, chewed or kinked cable and for water ingress into connectors. If the cable is visibly damaged, do not leave it; call an engineer.

3) If the outside sensor is mounted externally (on an outside wall) check that the sensor head is still in place and not hanging loose or submerged in debris/water.

4) Check the plug/connector on the boiler’s control board: with the boiler powered OFF, open the small service flap or front cover only if comfortable and safe to do so. Ensure the connector for the outside sensor is fully seated and that the pins are not corroded. Reseat the connector and reapply power, then reset the boiler to see if the error clears.

Basic diagnostic steps (requires simple tools and electrical safety awareness)

1) With power isolated, locate the outside sensor connector on the PCB or wiring loom. Note the connector position and any markings so you can reconnect correctly.

2) If you have a multimeter and know how to use it safely, you can measure continuity of the cable: check for an open circuit (infinite resistance) or short (very low resistance) between the sensor wires. An open or short indicates a wiring or sensor failure.

3) Measure the sensor resistance directly at the sensor end or at the plug with the sensor exposed (power off). Most outside NTC sensors used by Worcester are around 10 kΩ at 25°C, but check your boiler manual or the sensor part number for the exact characteristic. If the resistance is wildly out of expected range (open circuit or near-zero), the sensor is faulty.

4) If the cable and connector test OK but the sensor resistance is incorrect, the sensor needs replacing. If the cable is damaged, replacing the cable or sensor assembly is required.

What to do next / replacement and professional involvement

1) If any of the above checks show a clear wiring fault or a bad sensor reading, or if you are not comfortable performing the multimeter checks, book a visit from a Gas Safe registered engineer. They will confirm the fault, fit the correct replacement outside temperature sensor or cable, and reset and test the boiler control and weather-compensation functionality.

2) If reseating the connector temporarily clears the error but it returns, this indicates an intermittent connection or failing sensor and still needs a professional repair to avoid repeated faults.

3) If your boiler shows other fault codes or if the boiler won’t run normally for heat or hot water, stop and call an engineer — don’t continue to try repairs that could affect safety.

Final notes

1) Replacing sensors and working inside the boiler should be done by a qualified engineer to protect safety, preserve warranty and ensure correct parts and settings. 2) The 1037 error itself is not normally an immediate safety hazard but will affect control and efficiency; get it fixed to restore proper operation and prevent other faults.