Thawing frozen pipes
How do you know your pipe is frozen? After a bitterly coldnight, you turn on your tap and instead of a steady gush of water you get asickly trickle followed by...nothing. Since water expands when it freezes -- andpipes don't -- a frozen pipe is in danger of bursting. It needs to be thawed.
First you need to find out where the pipe is frozen. Turn off the main watersupply. This will prevent the water from gushing out once the pipe is thawed. Thenopen the taps in the house.
- If water isn't running anywhere in the house, a pipe near the water meter may be frozen. Touch the meter and the adjacent exposed pipes. If they are very cold, they are probably frozen.
- If water runs in only one part of the house, a pipe in an outside wall or un-insulated crawl space is probably frozen. Open kitchen and bathroom sink cabinets to allow warm air from the house to warm the pipes.
- Once you've found the frozen pipe, open the affected faucet all the way, and open other hot water faucets in the house. When the water is flowing in the affected pipe, close all the faucets to a trickle. Do not close the affected faucet until the pipe is completely thawed and the water flowing freely.
The safest -- and neatest -- thawing methods involve a gentle heat sourcehair dryer, heat lamp, or household iron. A propane torch or other open flamewill heat the pipe too quickly and may cause it to explode. Some peoplerecommend pouring boiling water over rags wrapped around a frozen pipe. Theobvious drawback is that this method is messy. Never pour boiling water directlyonto a frozen pipe.
When thawing pipes with a heat lamp or hair dryer always work from an openfaucet toward the frozen area. This will keep steam from being trapped by iceand bursting the pipe. With the faucet open, you can see when the ice hasmelted. Do not use un-grounded electrical appliances outdoors, or near groundedwater pipes.
To prevent pipes from freezing in the first place, wrap electrical heatingcable around it--one turn every two feet--then cover the pipe with insulation toconserve the heat. Follow all directions on the heating cable and take specialcare not to overlap the cable. Plug in the cable when the temperatures dropsbelow freezing. The same cable device can be used to thaw a pipe. -- MichiganState University Extension.
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