Let me give you a few details that I left out. And one thing from today:
1. There is no wet spot in the house or in the yard and nowhere that I can see water would be going unless it's being absorbed into the ground under the slab.
2. The faucet had been dripping on the cold side so I thought there might be a problem with the valve on the hot side too, and maybe both sides were bad. So rather than buy the parts and fix a cheap faucet I decided to go and get another one and replace it. So after I replace the faucet the pressure on the hot side is still low. And the air in the line is still there.
3. Today when I got home from work I went to the water meter and watched for the wheel to turn. It was not turning at all. I got my son to turn the water on to just a drip and was able to see the will move very very slowly. So when I asked him to turn the water on halfway, you could see the wheel turning pretty good even though it was slow. So I'm not sure if I have a leak and I don't see how I could have a leak if the wheel is not turning on the meter.
4. I think I may have an idea of where the air is coming from in the faucet even if there is not a leak. On my hot water supply line the tap for the dishwasher is before you get to the valve for the sink. So I'm thinking when we run the dishwasher all of the water from the hot side of the faucet runs down into the dishwasher. I'm not sure if that's possible.
5. Last night when I change the faucet I could not get the hot water supply valve to turn off completely so I had to turn the water off at the meter. I also noticed when I tried to turn the water off at the supply valve it was leaking around the valve stem and the pack nut. I'm not sure if something is wrong with the valve Maybe some calcium deposit or something is stopping the valve up and cutting into my water pressure or volume going through the valve. Given the fact that there seems to be no leak this may be the most likely Theory.
6. I think I should also mention that I drain my water heater Last Summer and had what looked like coarse ground salt coming out of the hose. There was maybe a handful of it on the ground after the tank drained. So if I do have minerals build up in my tank maybe they are going through the hot water line and out to the kitchen sink. This would also make the clogged supply line valve Theory more believable.