A frozen well pump means no water in the coldest weather. Here is how to prevent it from happening and exactly how to safely thaw one that has already frozen.
Submersible pumps deep in the well are almost never at risk — groundwater temperature stays above freezing year-round. The vulnerable components are above-ground: the pressure tank, the pipes between the well head and the house, the jet pump (if above-ground), the well head cap, and any exposed fittings.
If your pump is in a well house or pump shed, insulate the walls, floor, and ceiling. Close all gaps and cracks where cold air enters. Even an unheated but well-insulated structure retains enough ground heat to prevent freezing in most climates.
Self-regulating pipe heating cable wraps around exposed pipes and automatically adjusts heat output based on temperature. It is the most reliable freeze protection for exposed pipes. Install it on any pipe section that is above ground or in an unheated space. Cost: $0.50-1.50 per foot plus thermostat ($30-60).
A small electric heater with a frost-protection thermostat (set to 40°F) in the well house turns on automatically when temperatures drop. This is the most complete protection for jet pump setups. A 200-watt heater is sufficient for most small well houses.
Opening a faucet to a slow drip keeps water moving and dramatically reduces freezing risk. Use a faucet at the end of the line farthest from the pump. This wastes some water but protects the system during extreme cold snaps.
💡 After thawing: Check every fitting, joint, and the pressure tank for cracks or leaks. Frozen water expands with enough force to crack cast iron and split copper pipe. A hairline crack may not be obvious until water pressure is restored.
An undersized tank causes low pressure, short cycling, and early pump failure. Check yours free in 2 minutes.
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