Check water and gas piping

What is going on

With the cover off the TRX150, I always walk the piping before anything else. Most callbacks I see on boilers trace back to a slow weep at a fitting or tired glycol, and both are easy to catch on a visual. The gas side is a different story, and any smell means stop and call a qualified tech.

Likely causes

• Slow leak at a water connection, pump flange or fitting
• Water or antifreeze mix gone acidic or old, with pH below the manufacturer limit
• Different antifreeze types mixed in the loop

Check in this order

1. Remove the boiler cover and perform a gas leak check. If you find a gas odor or a leak, call a qualified service technician.
2. Check the boiler water connections, heat exchanger and external piping, pumps and fittings for leaks. Have leaks repaired at once.
3. Check the pH of the water or antifreeze mix regularly and replace it when it falls below the manufacturer limit.
4. Do not mix different types of antifreeze.
5. Look for stains, crusting or damp insulation, which show slow leaks.

More boiler guides

• Access the low voltage wiring connections
• Blocking errors versus lockout errors
• Blower not running
• Blower runs at high speed with burner off
• Boiler bangs or hisses; Lockout 81 delta T
• Burner not running on a call for heat