Frost Nights Find Exposed Pipes. Thaw Them Without a Flame

Paso Robles has no snow to speak of, but clear winter nights drop below freezing often. NOAA's 1991-2020 normals for the in-town station count an average of 54.3 freezing nights, 32°F or colder, in a year, and 18.0 of them fall in December alone. The airport station, which sits in a different spot, averages 45.0.

When does the freeze season run?

At the in-town station, the median first freeze of fall comes around November 10 and the median last freeze of spring around March 15. Expect cold mornings in that window, with the hardest stretch in December and January.

The lines most at risk are the ones outside the heated house: the run from the well and pressure tank, pipes to and from a water storage tank, a booster pump, hose bibs, and pipes in crawlspaces and attics of an older ranch house. The water heater's relief-valve discharge pipe also must not be exposed to freezing, its maker's manual says; never cap or plug it to stop a drip.

How do you thaw a frozen pipe safely?

Open the faucet first, then warm the pipe gently. The National Weather Service says to turn on the faucet, since water will drip as the pipe warms, and to use a space heater, heating pad, electric hair dryer or hot water on a cloth. Never use an open flame.

The American Red Cross adds to keep the faucet open, keep a space heater away from anything flammable, and never use a blowtorch, kerosene or propane heater, charcoal stove or other open-flame device. If you cannot thaw the pipe, or you cannot reach it, call a licensed plumber.

Sources

1. NOAA NCEI — 1991-2020 normals, Paso Robles USC00046730 — freeze nights and dates
2. NOAA NCEI — 1991-2020 normals, Paso Robles Muni Airport — 45.0 nights at the airport
3. National Weather Service — Essential Tasks After it Warms Up — thawing steps, no open flame
4. American Red Cross — Preventing and Thawing Frozen Pipes — heat sources to avoid
5. A. O. Smith — Residential Gas Water Heaters manual — relief discharge pipe and freezing