To hot or not ???????????

You  say it gets quite a bit hotter than when you had it plugged into the wall.  what is it plugged into now?

If you look at the back panel of your amp, on the left side toward the bottom, you'll see it's maximum rated draw is 12 amps. 

Your TV an sub should also have their max draw figures on them, so you can add them all together and see if they exceed 20 amps.

Note that the amp will only draw the full 12 amps when all seven channels are cranking at full power all at once.  That's relatively unlikely, and even then, will probably not be more than a momentary event.

Hey,

The only reason your amp has of being "hotter" is if the voltage is significantly higher.

I see the AVR 20 has built in voltage regulation. It’s worth examining the voltage at your wall. It shouldn’t be that low. If you find it significantly under 115V, or the neutral to ground elevated over 2V you should call an electrician. If you don’t have a voltage meter, or are uncomfortable probing your wall sockets I recommend this one, for $20 it’s perfectly safe and measures everything at once:

Also, measure the voltage at the wall WITH the AVR in place. If it’s causing a large sag it is, again, worth discussing with an electrician. I love voltage regulators, and use one, but they work by drawing more current. That can make existing upstream problems worse. 

Best,

E

OH, yeah, plugged into a balanced transformer the meter I recommended will show ~ 60 N-E, that's fine

*too

The amp rating on the wall plug and breaker should have no bearing on your equipment.  The voltage is the thing.  The size of the breaker only regulates the total draw the line can provide.  Your equipment will only take the power it needs and is designed to handle.  A larger amp supply doesn't "force" more power into your equpment.  You only need to check that your line voltage is the same as your equipment.  

Here is another option for s tester:  Fluke ST 120 + GFCI Socket Tester (19.88 on Amazon ).

Here is another option for a tester : Fluke ST 120 + GFCI Socket Tester with audible beep - 19.99 on Amazon )

@erik_squires

For what it's worth, I've had 3 of the kaiweets tester and they all measured my line voltage at 114V.  Further testing with a fluke meter (and confirmed with another good DVM) showed that these readings were off and my actual line voltage was 121V.  I kept one around for the features other than measuring line voltage, but YMMV.

@skucie Good to know!