Ask the Expert

Question: Furnace Filters

Can you tell me how often I really need to replace my furnace's filter? I have heard that service men always tell customers they need a new filter and it is just to increase their sales.  - Mary, Wauwatosa


The Expert Says...

This is a great question because the filter is a very important part of your heating & cooling system. It is crucial to the performance of the units that the filter be checked and changed on a regular basis. The filter performs one main function, with two major benefits. Your furnace's blower circulates air throughout your house, picking up dust, dirt, hair and all sorts of impurities along the way. The filter is located so that when the air that has been circulated through out the house is being fed back to the furnace, it catches the dirt and dust and removes these particles from the air, preventing them from entering the furnace and corroding the inside.

One of the main reasons we get repair calls is due to a dirty, corroded system - the filter helps prevent that from happening. Also, when you look at a used filter you will see everything that, if it hadn't been caught by the filter, would have kept recirculating throughout your home. So, in the end your filter helps protect the furnace itself and helps prevent impurities from being breathed in by you.

How often you change your filter will depend on the size of the filter you have and the traffic in your home. A good rule of thumb is to check your filter once a month and replace as needed - when you see that it is becoming dark and clogged. Usually the thin, 1 inch filters need to be changed once every 1-3 months and the thick, media filters every 6-12 months.

Thanks for the question. When it comes time to replace your filter, keep us in mind - we stock a wide variety!



Question: Air Conditioners in Winter


Is it necessary to cover my air conditioner in the winter?  - Rosie, Waukesha


The Expert Says...

Air Conditioners are built to be extremely durable and are able to withstand even the harshest Wisconsin winters. While your unit will not be damaged by the snow and rain, it is a good idea to cover the top of the unit to prevent leaves and other debris from floating in during the fall. There are air conditioner covers available for this purpose, but, these covers create a "warm and cozy" place for mice and other rodents to seek shelter in. For this reason, we suggest simply placing a board on top of the unit with a heavy weight to hold it down. It is important to keep in mind that this should only be done when the unit is not
running - covering the top of the unit while it is in operation is detrimental to the unit's performance.



Question: Birds Nesting Where They Shouldn't Be

Can I put a screen over the opening of my PVC pipe to prevent birds and mice
from building nests and entering my home? - Tammy, North Prairie


The Expert Says...

This is definitely not recommended. In the winter the hazardous fumes being vented out of the PVC pipe are extremely hot. When these fumes hit the cold air, they condense forming moisture on the pipe. This moisture then turns to ice, which is why you can often see icicles hanging off of PVC pipes. If there was a screen blocking the opening, the water
would form on it and then proceed to ice over, completely blocking off the venting and leaving the fumes with no way to reach the outside.


Question: What about Federal Tax Credits?

Here is a great article from The Journal Sentinel here

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