Hot tips for avoiding frozen pipes with This Old House plumbing and heating expert Richard Trethewey
1. Shut off the main water valve, which is typically located near the water meter.
2. Drain hot and cold water from house by attaching a hose to sill cock or basement faucet; drain the water into a sump-pump pit or to the outdoors.
3. Open all faucets and flush all toilets in house, starting with top floor and working your way down.
4. Close all the faucets in house.
5. Connect an air compressor to an open sill cock or basement faucet and blow air into the system at 70 pounds per square inch (psi).
6. Open sink faucets to allow water to blow out.
7. Turn on the dishwasher and allow it to run to clear water from the drain line.
8. Run both hot and cold water through the washing machine to flush out the lines.
9. Open the shut-off valve beneath each toilet to allow compressed air to blow out water from water-supply tubing for a few seconds, then close the valve.
10. Pour propylene glycol into every sink and tub trap.
11. Add a little propylene glycol to every toilet tank.
12. Drain any water left in the boiler into a bucket, and then pump propylene glycol back into the boiler's piping.