During the cold winter seasons some homes in the area have experienced broken pipes.
POSSIBLE CAUSES
There are a number of root causes of pipes freezing, each important on its own, but as a combination is believed to be the main cause.
Failure to drain the pipe. An empty pipe would never burst, now matter how low the temperature gets outside.
The pipe has to be completely drained. Close the inner valve (Vi) and open the outer valve (Vo) to drain the gardening pipe.
A frozen garden hose can burst an interior pipe. When the water in the hose freezes, it expands, increasing pressure throughout the whole plumbing system. As part of your regular seasonal maintenance, garden hoses should be disconnected, drained, and stored before the first hard freeze.
Old and malfunctioning valves.
In many units the valves are old and function improperly. Inability to completely open the outer valve (Vo) would result in poor or incomplete drainage of the pipe. Slight leakage of the interior valve (Vi) could cause the water to freeze in (Vo) when temperatures dip and slowly fill and freeze throughout the entire pipe, causing it to expand and burst.
Warp and droop of the gardening pipe.
Warp and droop of the gardening pipe (common occurrence in many units) would make complete drainage impossible.
RECOMMENDATIONS
Replace the old valves. “Stop and Waste Ball Valve” is recommended for inner valve (Vi).
It’s a good idea to open the ceiling, inspect, and if necessary, replace the pipe(s) as a preventive measure. The pipe should be straight and installed with a pitch (slope), which will facilitate drainage. The pipe should not run along the window or a cold wall. Choose an alternate route. Enclosing or wrapping with insulation should protect the pipe.
Additional thermal insulation may be added behind the section of the perforated siding over the air conditioner, if needed.
IMPORTANT: Close (Vi) and then open (Vo). Unscrew the cap and leave it open throughout the winter to facilitate the pipe drainage.
Contact a licensed plumber.