Can I use a BoAir 5 stage air filter with a geothermal system? The unit is 8 1/2 years old. I have a metal filter that you hose off just like the BoAir 5 stage, but they said it would last 8 to 10 years.
My thermostat is showing it needs changed. I did clean it and replaced it in the unit but it is still saying change. Thank You.
Upgrading to a BoAir 5 Stage Electrostatic Filter
If you are currently using an electrostatic air filter in your geothermal heat pump I see no reason not to upgrade to the BoAir 5 Stage electrostatic filter. It is probably the most efficient electrostatic air filter available. However, without seeing your old filter, I can’t say if you need to replace it or not.
I looked at a friends heat pump the other day and he was using an electrostatic air filter with a metal frame and the filter was still in very good condition after 10 years of use.
Regarding the Thermostat Filter Change Indicator
There are Two Types of Filter Change Indicators
Thermostat Timers – not a good solution
1) This type has an electronic timer in the thermostat that is used only as a reminder to change your air filter at pre determined intervals. Depending on the type of thermostat you are using, the intervals can be based on hours of operation or days of operation. These times are usually programmed into the thermostat when they are installed and can be adjusted later if necessary, or even disabled.
Every time the filter change indicator illuminates on the thermostat it must be reset so that the timing sequence begins again from zero. Resetting these timers is typically done by pressing a button or a combination of buttons. Sometimes they can be a bit tricky to figure out because each manufacturer has there own way of doing things. You should refer to the manual for specific instructions for your thermostat.
These filter change indicators do not reset automatically, so you will have to reset it yourself. If you are unsure how to reset it contact the manufacturer or a local contractor. You may also be able to find this information by doing a search online for the manufacturer and model number of your thermostat.
If the thermostat will not reset and you are sure you are using the proper procedure, you will have to change the thermostat. These filter change indicators are only reminders and do not indicate if the filter is actually dirty or not.
Air Filter Gages – The best solution
2) The second type of filter change indicator is the filter clog switch. These are much better devices than thermostat timers and are activated when the furnace filter or air conditioner filter becomes dirty.
Unfortunately these types of filter change indicators are not often used in residential heating and air conditioning equipment due to the additional costs associated with installing them. Although not overly expensive, for some reason contractors don’t usually offer them. Typically they try to keep costs low in order to make more sales.
An Option for Home Owners
There is an aftermarket filter change indicator available that can be easily installed. It’s the G99 Air Filter Gage made by GeneralAire. You should also include the G99-14 Air Gage Remote Mount Kit. The kit allows for installation up to 10 feet away from the air handler.
These filter change indicators sense air pressure and react to air pressure changes within the air handler. As your air filter becomes dirty the air pressure in the air handler changes causing the indicator needle to move.
Basically what happens is, as the filter becomes dirty the pressure drop across the filter increases. This restriction to air flow causes a pressure change that the filter change indicator (air flow switch) reacts to, telling you it is time to change your air filter because it is getting dirty.
There are Two Things That Can Cause This Type of Filter Change Indicator to Indicate a Dirty Filter Incorrectly
1) If the air flow switch is not calibrated properly it may indicate that the filter needs to be changed when it doesn’t or it may not indicate the filter is dirty at all, when it fact, it is time for it to be changed or cleaned.
2) The other thing that can cause this type of filter change indicator to give false readings and is relatively common in heat pumps and air conditioners that are have been in service for many years and systems that use inefficient filters, is a dirty evaporator coil.
Before making any changes to the settings of the air flow switch, inspect the evaporator coil and make sure it is not dirty and restricting air flow. A dirty air filter and a dirty evaporator coil show the same symptoms, so if everything indicates a dirty air filter but you know it is clean, check the evaporator coil.