EP 4000 as a subwoofer amp?

Let me put it this way: 

Properly rated amplifiers of worthwhile quality

cost at least $2.00 per watt.

That should tell you something important.  

And... Most subwoofers suited to home use have built-in amplifiers, 

which eliminates the need to consider what to drive them with. 

I would go that way unless I was doing something particularly special,

in which case I would want a MUCH better-quality amplifier 

than anything Behringer ever has or ever will make.  

I assume the receiver has a SUBWOOFER output of some type. If it is not an analog output you will need to buy a cheap converter on Amazon or whatever to convert it to analog.

The EP4000 is an excellent subwoofer amp and you can run it in bridged mode if you have only one subwoofer. Keep in mind it puts out around 3000 watts into 8 ohms or 4000 watts into 4 ohms in bridged mode. Most home theater subs will not be able to handle that much power. A good 18 inch professional sub will work fine.