I've been using Leonard Rose and Sons for ten years. They've been serving Doylestown since the stone age.
Recently they saved me a bundle of money by going out of their way to diagnose a problem with my hot water heater. It's a good thing I had a leaky pipe because my hot water tank was corroded, it was almost rusted through on the bottom. Just a small leak, and I didn't see the problem until they took the tank out. They also called the company for me to find out if it was under warranty. Lucky me it was replaced for free and I'm more than happy to pay for the labor which was done quickly.
Pros: Prompt, courteous, professional, honest, reasonable rates,