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Frequently Asked Questions


How often should I change my furnace filters?

1" filters need replaced every 30 days
2" Filters 30-60 days
4" filters every 6 months - checked every 3 months.

What is the expected life span of air conditioners and furnaces and how do I know when to replace before total failure?

Industry life expectancy for furnaces and air conditioners can vary due to wear and tear, installation and product line. A safe bet is 18-20 years. I wouldn’t suggest replacement if you are not having issues, or if it passes safety/maintenance checks. Heat Pumps and Air handlers are different, in the aspect of they are used all year around for heating and cooling. A safe bet would be 10-12 years. This is also dependent on wear and tear along with maintenance. Any piece of equipment can last longer than the “projected lifespan.” It becomes a question of efficiency and reliability.

What sets Duff’s Mechanical apart from other HVAC contractors in the Columbus area?

We, here at Duff’s, treat our customers as friends and family. No bait and switch, no hidden fees, no pressure. We treat every house as we would our own, as all contractors should. We want your total satisfaction when we complete a service or an install. At the end of the day, it is about being comfortable in your own home!

What preventable maintenance is necessary and why is it important?

Most issues are based upon air flow and part failure. Homeowners can do these 2 simple things. 1: Changing the filter is a must, can be done by anyone, and is the easiest.2: A step up from that would be flushing the Air Conditioner, Heat Pump or Mini Split condenser with water - Not a power washer! Simply using a hose and spraying downward will work just fine. 

Aside from the above, a service tech would be suggested for annual maintenance, normally starting a year or two after installation. Normally, air conditioners would be serviced in early spring. Furnaces in early fall along with heat pumps and air handlers. The idea is to service them before the season in which they will be most used.

Annual maintenance services would include but are not limited to checking refrigerant levels, capacitors, temperature rise, Carbon monoxide testing, amp draws, and gas pressure. Many times issues can found eve fore major issue through these checks. E.G. Finding a dirty blower wheel, or plugged evaporator coil, closed dampers, blocked returns or registers.

Always remember, air flow can make or break the efficiency, reliability and comfort level in a home!

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