NTI Boiler: Blocking errors versus lockout errors
Blocking errors versus lockout errors on a NTI boiler: There are two kinds of error on this boiler and they act differently, so it helps to know which one you are looking at. A blocking error clears by itself once the cause goes away, and the boiler restarts on its own. You can spot it because the display shows the blocking symbol ahead of the code. A lockout error stays put until the cause is fixed and someone presses the Reset button. If either one keeps coming back, that is a sign something real is going on, and it is time to call a qualified service technician.
Applies to: TRX150
Common causes of blocking errors versus lockout errors
- Temporary condition such as low water pressure, high temperature or a sensor reading out of range (blocking)
- A safety fault that needs a manual reset, for example a failed ignition (lockout)
- Repeated error 108 with frequent refilling points to a water leak in the system
- An underlying fault that clears and returns, so the same code shows up again and again
How to fix blocking errors versus lockout errors: step by step
- Look at the display and note whether the blocking symbol appears before the code. If it does, the boiler restarts on its own once the cause clears.
- Write down the code before you reset anything, so you can tell a technician exactly what you saw.
- For a lockout, find and fix the cause first, then press Reset. Resetting without checking just repeats the lockout.
- If a blocking error continues, call a qualified service technician.
- If error 108 keeps happening and the system needs repeated refilling, turn off the boiler and its power, shut off the main gas valve, and have a technician check for water leaks.
- Check the system pressure gauge and look around the piping for wet spots or drips while you wait.
If the unit shows an error code, look it up: NTI Boiler codes
Models
TRX085TRX110CTRX150TRX199TRX199C
Source: NTI TRX150 manual, p. 83. Written in our own words as a summary; always check the original manual.
General guidance for qualified technicians. The manufacturer's installation and service manual and local codes always take priority. Aurora Star Tech is not affiliated with, endorsed by or sponsored by any equipment manufacturer; brand and model names are used only to identify equipment and belong to their owners.