High power switching circuit problem.

Hello all. I am trying to use a mosfet as a high power switch. I have an arduino nano pin controlling the gate of the fet. I am using an NTE2374 mosfet. I am using a typical circuit:





I also have the gate connected to the source (ground) so that when the gate is not HIGH, it isn't floating.



I have been testing this circuit on two separate components; main component (the valve) and also on an LED (not sure if this is a good idea). I have found the following things to happen:

• When the arduino pin output is LOW and the component is either a valve of LED, the
  
  component was off (as it should)


• When the arduino pin output is HIGH the LED turns on.


• When the arduino pin output is HIGH the valve does NOT turn on and the voltage reading on
  
  my dc power supply goes from 15V down to zero in a moment.

I have been at this for a couple of days and I can't seem to figure out what the problem is. Can anyone help me out or direct me towards the correct path? Thank you.