HVACopedia

NTI · Boiler troubleshooting

Drain the domestic hot water system and indirect tank

TRX

What is going on

DHW side and indirect tank on the TRX150. Drain it any time freezing is a risk. Empty means empty, no pockets left to split a pipe.

Likely causes

  • Vacant or unheated building during cold weather
  • Water trapped at low points after shutdown
  • Taps left closed, so air cannot get in and water stays in the pipes

Check in this order

  1. Shut off the main water inlet valve.
  2. Open all hot and cold water taps to let air in.
  3. Drain water from the lowest points of the system.
  4. Also drain the indirect tank at its drain valve.
  5. Leave the taps open until the building is heated again.

Applies to: TRX150

More boiler guides

Related

NTI error codes · NTI parts · NTI tips · Calculators and reference tables

Take it to the job

All guides, error codes and tips work offline in the HVACopedia app.

Open the app

Source: NTI TRX150 manual, p. 89. Written in our own words; check the manual for your exact model.

For licensed technicians. Gas, electrical and refrigerant work must be done by a qualified, licensed person. Shut off power and gas before servicing, never bypass a safety control, and follow the manufacturer’s manual for the exact model; it and local codes always take priority. HVACopedia is not affiliated with any manufacturer; brand and model names only identify the equipment.