Regardless whether it's your HVAC unit, your car, or some other device, it's easy to feel caught in the middle by "finger-pointing" from different service companies. See if any of these sound familiar:

• Company B tells you they need to install a new part that Company A just recently replaced.
• Company B says that Company A did something wrong and they are having to un-do it or re-do it.

What should you do? You're probably not a technical wiz about the issue – that's why you called a service technician to begin with!