How does one unthaw a frozen vent stack on the roof ?

How does one unthaw a frozen vent stack on the roof ?
One pours hot water down the vent stack. Hopefully the ice plug won't be so large that the hot water freezes before it melts the ice plug. If it's froze in the attic a hair dryer played on the pipe might help. Good luck,tom

It takes guts to get on a frozen roof. I would not get up there. The roofing up north is steeper than the roofing down south.

How does one unthaw a frozen vent stack on the roof ?
One waits until the vent thaws itself out all by itself.

How does one unthaw a frozen vent stack on the roof ?

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