I thought about the same thing. I have a pretty vast background in electronics and from experience I would say its a bad idea because the float valve is now handling full line voltage. You would have to use a relay and the time, parts and energy required would outweigh the $12 for the battery air pump.
It would work without the relay by itself (splicing into the power cord) but in no way could I leave for a week and trust it. For me, the $12 for the battery air pump was worth the piece of mind that $12 could have save my office from burning down.
It would work without the relay by itself (splicing into the power cord) but in no way could I leave for a week and trust it. For me, the $12 for the battery air pump was worth the piece of mind that $12 could have save my office from burning down.