First I would like to thank you in advance.

I have a complete 5 tons (from what I heard) gas heat system. My outdoor model is TTN060C100D0.

I had problem and called a service man out. He said that my thermal valve was bad. It was connected on the outside of my coil above my gas heater. I agreed to have it replaced. After he had replaced it., he gave me the old valve and shooked the bulb and told me it was bad. I could hear and feel something was loose inside the bulb.

The valve he replaced was not exact like the one he took out. It was a bigger valve. The valve number I could read was SVE-4-CP100. But there was one small line he DID NOT connect like the old valve. The old valve had a 1/4 inch line connected to it from the big freon line. I asked him but his reply was "the old valve was external equalizer, and the new valve was internal equalizer". The unit runs cool but not as well as It used to. Thus, I have some questions to ask:

Question 1: What does that 1/4 inch line on my old valve do?

Question 2: when the bulb on the valve make noise like I described, that means the valve is bad? Because the new valve make no noise when I shook the bulb.

Question 3: On my new valve, the number 4 is for my tonnage? whereas I have 5 tons right?? And the CP100, what does it mean?