Said It Here

Water leak from screw after flushing water heater

Flushing a tankless water heater for maintenance can cause a small water leak to develop around a housing screw or union. This usually happens because the screw acts as a penetration through the housing, forcing homeowners to try tightening the fittings themselves or risk calling a technician before the problem worsens.

What people tried

Every workaround mentioned in the threads below. We haven’t tested any of them — and nobody here is claiming they worked.

  1. 1
    Tightening the union fittings
  2. 2
    Calling a technician

In their words

Unedited, most upvoted first, each linked to the thread it came from.

I have a small leak coming from a screw.source ↗

this happened after I flushed the water heater last week.source ↗

evasquez909 · r/Plumbing · 2 upvotes

If its on the union, tighten the union and pray. If its from the screw, its inside the cabinet and using the screw as a penetration through housing.source ↗

Krull88 · r/Plumbing · 1 upvotes

Thank you. I didn’t want to call a technician but I don’t want the problem to get bigger.source ↗

evasquez909 · r/Plumbing · 1 upvotes

Where this came up

People with this problem also raised