"Ken Hall" wrote in message

Question 1:
I read you should replace the cheesy plastic drain cock with a ball
valve so you can get full flow when draining the heater. But, there's
some kind of safety cover over the drain cock that prevents putting
ball valves (which are larger) on them. So, if you can't do it, why
is it recommended?

Because it is a good idea if done properly. Sounds like they don't want you
to in this case.

Question 2:
This is a self-cleaning unit. Do you drain self cleaning units? Is
so, doesn't that mean they're not self cleaning?

This is probably the reason they don't want you to change the valves. I
have no idea how well this works.



Question 3:
Sure enough when he cracked open one of the connections a
lot more water drained out. Why does a connection at the heater
have to be opened to get it to drain completely?

Vacuum. Put a straw in a glass of water. Put your finger over the end and
lift it out. Same thing with the heater. If air is not allowed in, the
water cannot get out.