Water heater is leaking from the bottom or around connections; puddles form under the Nibe cylinder.

Safety first: Turn off power immediately if water is leaking near electrical components. Close the cold water supply to limit flooding.

• Step 1 – Identify leak source:
  • Dry the area and observe where water reappears: from fittings, safety valve discharge, or tank body.
• Step 2 – Check fittings:
  • Tighten accessible unions and compression fittings gently; do not overtighten.
  • Inspect the immersion heater flange for signs of seepage; retighten bolts evenly if needed.
• Step 3 – Safety valve:
  • If water is coming from the safety valve discharge, check system pressure and expansion vessel function.
• Step 4 – Tank body:
  • If water seeps from the tank shell or insulation with no visible fitting leak, the cylinder may be corroded internally and require replacement.

Do not attempt to weld or patch a pressurized cylinder. Contact a qualified plumber or Nibe service partner for tank replacement if the shell is leaking.