A: It sounds like you have done about all you can as a homeowner and you probably need to call a pro to troubleshoot and repair it for you.

I understand a homeowner's frustration with calling professionals because their time seems so expensive, especially when they can fix something within a few minutes but still charge at least a one hour minimum.

However, it is important to understand that you are paying for their professional expertise, including years of experience, training and special tools that allow them to diagnose and fix problems quickly, as well as the cost of being in business. Someone with less experience (like a general handyman) could spend hours ruling out possible problems or running to the hardware store buying parts to try this or that. At some point, hiring a knowledgeable professional who will warranty his/her work is the most efficient, economical, sensible choice.

I suggest you call a few heating and air conditioning companies, explain your problem and your attempts to fix it yourself, and see if they can give you some ideas to try, or estimate what it would probably cost to hire them. Most companies don't give free estimates for service calls and will charge you if they come out and you don't hire them to do the work. However, if you do some comparison shopping over the phone to determine their minimum fees, hourly rates, schedules, warranties, etc., you should be able to avoid any extra service or trip charges by choosing one company to come do everything for you in one trip.

To locate reliable heating and air conditioning specialists to contact, visit Home Advisor, select the type of heating system you have so we can refer you to the ideal service professional in your area.

by Kathy Maynard, reprinted courtesy of HomeAdvisor.com