On Tuesday, January 24, 2017 at 7:25:19 PM UTC-5, wrote:
On Tue, 24 Jan 2017 16:12:08 -0800 (PST), trader_4
wrote:

If the battery pump can keep you safe long enough to get a new AC pump,
that would be good enough reason for me to keep doing what you're doing.
I'd have the battery pump set to come on at a higher level and also an
alarm set up to sound so that you know the primary pump has failed.
They have cheap $10 alarms for water heaters at HD and similar. May
be loud enough and work for your purpose.

Why would you put an alarm on a water heater, and where does it connect?

You put it on the floor or in the safety drip pan that's under it,
if it has one. It's just a battery operated alarm, the size of a pack
of cigarettes, with two contacts on the bottom. If the WH starts to
leak, you know it before it does damage.