Tired of dumping dehumidifier... Float switch, submersible pump, and a timer?

I have a small dehumidifier with a removable tank that has to be emptied far too often.   It has an integrated float switch in the tank that shuts down once full, but if you neglect to dump it, the basement gets way too muggy.

I would like to put in a submersible pump (like this) that is activated by a simple mechanical float switch.  Once activated, I only want the pump to run for a set amount of time, in order to keep the pump from pumping all the water out and running the pump dry.  I thought about this timer, which has a minimum interval of one minute.  One to two minutes of pumping would be about right for the tank size, depending on the pump flow rate and where the float switch was set to initiate the pump.

I had originally looked at a Kerick Valve float switch, but this will only let enough water drain out to lower the float and close the valve.  This will essentially just trickle out.

Any ideas on this?

I don't want to drill a hole in the tank and just run a drain tube... though I considered it.  Part of the reason is that I wanted to avoid just letting it trickle out.  And I also felt like I wanted to tinker just a little.  :)

I think something like this electric adjustable float switch for a submersible pump and a small submersible pump like these might be better.

You set the switch to turn on the pump at a certain level and off at a certain level.
mpilchfamily10 months ago
If all you want is to drain the water then i see no point in over complicating things. BUt if you wanted to pump that water to a large container to reclaim that water for use in a garden or something... Now that is worth doing IMHO.

There are plenty of sump pump options out there with built in water level indicators to turn the pump on and off.

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