Why must I replace my furnace when I change my air conditioner?

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Every year, thousands of Arizona residents email Rosie Romero's website or call his radio show with questions about everything from how to prevent fires in their chimneys to what to do about the tree roots invading their sewer systems. One of his goals is to provide answers that suit the specific lifestyle wherever someone lives in Arizona.

QUESTION: Why is it necessary to replace a furnace when you replace your air conditioner in a split HVAC system? Why not replace the blower motor instead? Or is it just "easier" to replace everything? Aren't we just creating junk sometimes when we don't need to replace things?

ANSWER: There are several reasons why both pieces of equipment in your heating and cooling system get switched out at the same time. The main one is that current air conditioners are much more energy-efficient than the ones produced 10 to 15 years ago. So you want to install a new air handler/furnace that has the same capacity and efficiency as your new air conditioning compressor. A mismatched system mixing old technology with new can decrease system performance and comfort. Replacing them both at once may also cost slightly less than replacing one part of your system one year and another part the next. If the AC needs replacing now, the air handler/furnace probably is getting ready to break down, too.

Q: You often recommend not using corrosive liquid or crystallized cleaners to clean drains to get rid of bathroom odors. My problem is a shower with an odor. Because the drain is in the shower floor, I can't remove the P-trap to clean it out as you would with a bathroom sink. So what can I use? I've tried the baking soda and vinegar thing, but the smell keeps coming back again.

A: Several products on the market use enzymes - not corrosive materials - to clean clogged, smelly drains. If you have a septic tank system, it's particularly important to use this type of drain cleaner every month to keep your system moving smoothly. However, even before you try an enzyme-based product, you can try mechanical means first. Simply unscrew the grate on the drain and use a plumber's zip tool to hook and remove hair or gunk caught in the drain. Then replace the grate and try the cleaner. That should give you a fresh start.

Q: When I remove my dishes and glasses from the dishwasher, they have a fishy smell. Recently, we drained the water heater to try to eliminate the odor, but that didn't help. If vinegar is added to the dishwasher, it seems to get rid of the smell, but I don't think we should have to try that all the time. What can we do?

A: Sometimes this happens because you're not thoroughly rinsing leftover food off your dishes. Then when you run the dishwasher, debris is removed but some still remains in your dishwasher. In summer, this debris builds up and starts to rot, producing an odor. Another possibility: You don't use your dishwasher regularly, perhaps because you are away from the house or you don't have many dirty dishes. When that happens, the water that remains in the dishwasher mechanism - water that you can't see - begins to get stagnant and develops an odor.

Another possibility may be that water from your garbage disposal is backing up into the dishwasher. That happens when a hose to the dishwasher, on a high loop under your sink, gets knocked down accidentally. You might start by checking that loop. Many times, it is just secured by a zip-tie.

You said you've tried vinegar. We recommend periodically placing a cup of vinegar upright inside the dishwasher and then running the wash and rinse cycle. Afterward, run the dishwasher with plain water only to get the vinegar smell out.

If all that doesn't work, you may want to buy one of the natural enzyme-eating products for dishwashers and washing machines that are on the market. You add this product to the dishwasher whenever you do dishes. Usually, that can kill all mold or mildew odors.


Story provided by aztarnet.com