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Everything Guide to Filters

Welcome to the "Everything Guide to Filters". Here you will find information on water filters, air filters, pool filters, spa filters, and appliance parts. We are working to constantly expand the information provided here. Please let us know if you have any questions you would like answered on these topics.

Water Filter Information

  • Q: I have a whole house filter at the point of entry for our house. We are on a well. I have a 20 GPM filter. I'd like to replace it with a 3 GPM filter. Will I be compromising our flow rate into our house with the lower GPM filter? Stated another way, will the flow rate at the point of use be reduced to a trickle?
    A: Point of entry systems filter water for your shower, hot water heater, dishwasher, etc. The flow rate for your filter should meet the water demand of each of these appliances measured in gallons per minute. Some typical ratings are listed below.
    Shower: 2.5 - 5 GPM
    Dishwasher: 3 GPM
    Larger homes require higher flow rates and a filter with a flow rate less than 10 GPM may cause pressure loss during peak use.

Refrigerator Filter Information

Air Filter Information

  • What is a MERV Rating?
  • Q: My home has three return registers. It has always had a 20x20x1 inch filter on one of the returns, but is it ok to put filters on the other two returns? If yes, should these filters have a much lower merv rating so they do not restrict air flow?
    A: You should consult your service manual regarding specifications for your particular furnace or air conditioning system before making any changes that could effect the air flow.

Pool Filter Information

Spa Filter Information

Appliance Part Information