I called this company out to look at my heating pump when it was giving me problems. They came fairly quickly. Looked at my heating unit. They found what they thought was the problem, but to make sure, they crawled under the house to check out the hookups and the vent system to make sure nothing was wrong down there. Even though that took an hour and wasn't really their responsibility, they charged me nothing for doing that.
PROS: Fast, Reliable, Reasonable