Too much wattage or voltage possible???

Okay my problem is that my 20 watt per channel rheobus will not supply all the power needed to run a 24 watt max. dc water pump. So, hooking up the pump to one channel will not run the pump at full power. to avoid frying my cpu, i need to connect the pump to two channels on the rheobus. My question is, can i hook up the pump to both rheobus channels and not have to worry about some voltage or wattage problem or worry about supplying too much wattage to the pump even when both channels on the rheobus are turned up all the way? I will really appretiate the help of anyone who knows enough about electronic power, voltages, wattages, etc., to answer my question. Thank you!!!!

Why does it have to be run through the reo-thing?

It would probably be okay to parallel it up, but both channels would have to be truned right up (and hopefully have well matched output voltages). The problems would start when you adjusted one or both of the controls and they start 'fighting' each other.

So, if you can't adjust it, why not power it directly???

Not a great idea, for the reasons above.

To answer your wattage problem, the pump won't draw any more than 24 watts at its rated voltage. You can't supply too much wattage unless you overvolt the pump.

Ken

It really depends what sort of fan controller it is, if it is a transistor based or PWM based one, it would likely fail, because a slight voltage differance will put a majority of the load on one module, however with a resistor based rheostat, it should be ok as long as you turn the dials somewhat together (like don't have them a quarter turn apart). Either way its not a great idea, but would probably work with a resistor based one.
Alternativly, you could take the output voltage and use it to power the base of a higher powered transistor such as a TIP122. It can handle 5 amps at 12 volts, costs all of 5 bucks and would only use one of your fan controller. HTH