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Navien Heat Exchanger Thermistor 30008366A

Navien

Navien Heat Exchanger Thermistor 30008366A

Navien heat exchanger thermistor, part 30008366A, identified by its blue wire and used across NCB boilers and NPE water heaters.

At a glance

  • Part type: heat exchanger thermistor
Manufacturer part no.
30008366A
Showing prices

£5.21

£4.34 ex. VAT · VAT at 20%

Available to order · 3 working days
Available to order · 3 working days
Not certain it's the right part? The technical team verifies fitment before dispatch — no charge, and it stops a second trip.Call the technical teamSend a technical question

Same-day dispatch

Ordered by 4pm Mon–Fri, 10:30am Sat.

30-day returns

Unused, in original packaging.

What it is

The Navien heat exchanger thermistor (blue wire) is a temperature sensor fitted to Navien NCB boilers and NPE water heaters. It reads the temperature at the heat exchanger and passes that signal to the appliance control board so firing and modulation can be managed. It is supplied under manufacturer part number 30008366A.

Signs this part needs replacing

  • The appliance locks out or fails to fire
  • Domestic hot water temperature fluctuates or runs cold
  • A fault code relating to heat exchanger temperature is displayed
  • Heating output is unstable or the boiler short cycles
  • The sensor's resistance reading is out of tolerance against the manufacturer's figures

Before you order

  • Confirm your appliance model and serial number against the fit list above
  • Check the wire colour on the failed sensor — this part is the blue wire variant
  • Inspect the sensor connector and lead for damage or corrosion before ordering

Not sure which part?

Search by part number, product name or brand — our technical team confirms fitment before anything is dispatched.