Scruffy_f - It is possible the check valve on the diffuser was not working if you shut off the compressor before it froze up. A leaky check valve will allow water to seep into the airline up to the water level where it freezes a plug in the airline. If this was the cause, it is a good idea to always clean the diffuser before winter operation. what type of diffuser and pump do you have??? If diffuser does not have a check valve, always expect the airline to freeze up whenever the compressor is shut off during ice cover. If that was not the problem, then condensation built up in the airline, and that accumulated eventually water froze a plug.
Operating a compressor with a plug frozen in the airline is very hard on the compressor if a pressure relief valve is not installed. I prefer adjustable presssure relief valves to accomodate various types of compressors and water depth situations. Aeration in winter's freezing conditions can be hazardous to the compressor (most expensive part of the system) if not done correctly and not using precautions.
If you want to thaw the airline maybe put the light bulb in an insulated box covering the airline and ground where the ground is frozen.
How much snow you got on the ice? How big is the pond (sqft)? It might be easier to go out and just shovel off an area 3X-4X times bigger area than the area that the compressor kept water open. It would not take a real big snowfree area for natural oxygenation if the pond is relatively small. Shovel an area away from where the aerator kept open water. Test your ice thickness before venturing out over water deeper than waist deep. On snow free ice I have walked on the ice to within 5-6 ft of the open water aera produced by a windmill membrane diffuser; testing the ice thickness as I approached the open water. In cold snowfree conditions, ice can be pretty thick close to the openwater zone produced by low volume diffusers operated by windmills.
Last edited by Bill Cody; 01/18/11 12:00 PM.
