Entries Tagged 'Filter QA' ↓

Question: I presently have a Honeywell f100 media filter. Would it be possible to replace it with a HEPA Pure and put a carbon filter with it and use the same housing that the Honeywell f100 currently has?  Will the HEPA pure cause an air flow restriction problem for my home unit?  How often to they need to change in an average home?

Really you have to decide which is more important, using the carbon filter as a secondary filter or using an efficient filter. You can use media filter pads which are decent filters and install carbon pads with them. With media pad filters you will be sacrificing some efficiency but carbon pads are available to use with them.

The Honeywell F100 has a MERV rating of 10 which is quite efficient.
Upgrading to a HEPA filter would increase filtering efficiency. HEPA filters have a MERV rating in the 14 - 15 range which is very high on the MERV scale.

HEPA filters are very efficient and they do restrict air flow. Any system that uses a HEPA filter must have a properly sized duct system and the filter must be maintained properly. If you have not had problems with poor air flow in your air conditioner you could certainly try one. Monitor the system closely for changes in operation. The best thing to do would be to have an HVAC technician check your system to determine if a HEPA filter is advisable. Many contractors don’t recommend using them because of the negative impact on air flow and operating efficiency but for a person dealing with allergies they are often necessary.

Another option is to upgrade to a Nordic Pure pleated filter which has a MERV rating of 12. This is between the one you are currently using and the HEPA filter. More about pleated air filters.

I would not recommend using a secondary filter with the Nordic Pure, the Honeywell F100 or a HEPA filter.

Question: I am having problems with allergies in Florida. As I am replacing our A/C unit I am looking for a really good filter. The Trane cleaneffect unit looks promising, but would it be good enough. Is it worth the extra cost to get a UV filter. Any recommendations would be appreciated. The installers have all been recommending not to use a uv type and just go with the Trane.

In my opinion, it depends on how bad your allergies are. If your allergies are very bad and cost is not a factor, I would say the extra protection a duct mounted UV air cleaner provides is not a bad addition to enhance a media air filter. UV air cleaners  kill bacteria, mold spores and other organic contaminants. That is something  a media air filter can’t do.

It’s also important to point out that a uv air cleaner is only suitable for enhancing the filtration of a traditional air filter and should never be used as the only method of air treatment. UV air cleaners do not actually filter the air, they only purify it by killing organic compounds. You still have to filter out those contaminants with mechanical filtration.

The Trane CleanEffects air filter is very efficient and Trane rates it even  better than a HEPA filter. That’s very impressive. I do have some concerns  about the Trane CleanEffects filter. You can read my thoughts in this post Trane CleanEffects Review.

That article is only based on what I have read about the filter because I  don’t have any first hand experience with it. I am hoping to get some comments in that post from people who are using it.

Question: If you don’t change your air filters and they are very dirty can this cause the central unit to freeze up? Will the unit be ok by changing the air filter? We had this happen 2 times before and we changed the filters. Our unit is only 2 years old.

Central air conditioner ice problems

Ice forming on central air conditioner coils is a common problem encountered by many home owners. This is usually attributed to poor air flow through the evaporator coil which creates low load conditions. Some of the most common reasons for poor air flow are undersized ductwork and dirty air filters. The result is evaporator temperatures at or below the freezing point which is 32 degrees Fahrenheit (0 degrees Celsius). Normal evaporator operating temperature for air conditioning equipment is above 32 degrees.

Usually all you have to do is set the thermostat setpoint above room temperature so the compressor doesn’t operate and this will allow the ice to melt. A better way to do this, depending on the type of thermostat you have, is set the fan to operate continuously and turn the cooling off. This keeps warm air moving through the evaporator coil and melts the ice much faster. Depending on how badly the unit is iced up, 30 minutes should do the job and 1 hour is even better to ensure all ice is gone.

Potential problems resulting from air conditioning equipment icing up

There are some potential problems with allowing an evaporator coil to freeze up. If the ice becomes bad enough it can actually cause the tubing in the evaporator coil to collapse or break. This requires a service technician to repair and possibly a new evaporator coil or worse. As you can imagine this is an expensive fix. Another problem with allowing the air filter to become this dirty is, equipment operating efficiency drops dramatically. The air conditioner will require longer run times to maintain space temperature and operating costs increase. You are much better off changing your air conditioner filters regularly.

There is also some risk of water damage when the ice melts. Often ice build up is bad enough to block drain openings and water overflows the condensate drain pan damaging walls, flooring and even ceilings if the unit located in your attic.

Question: Which pleated furnace filter is better from same company.
7 pleat or 11 pleat?

I would say the 11 pleat filter is probably better because more pleats per inch of filter allows for greater air flow. This is important for efficient filters. Quality manufacturers aim for as little impact on air flow as possible when designing their filters. As the efficiency of the filter material increases so does air flow restriction. One method of compensating for this is to have more pleats per inch of filter.

More pleats per inch of filter also distributes the dust collected by the air filter over a larger area and therefore can be in the system longer before needing to be changed.

Hepa air filters have many more pleats per inch than other filters that utilize the pleated design.

Question: You made an excellent Web site.  It is very informative and easy to understand. It is loaded with good information and excellent charts.  I just wanted to let you know that you did a first rate job.

I was recently told by the company that installed the HVAC system in my now 3 year old home, that it would cost $1800 to change the filters in my four air handlers. There is one Lenox Pure Air, MERV 9, Media Filter, 17” X 26” X 4” (part # 75X74) in each unit.  The $1800 includes replacing the UV bulbs in each unit also, approximately 18, 10M13 UV lamps in total. Also there is a filter-size, corrugated screen cartridge, behind the lamp units that says “do not wash”. I don’t know what the replacement status of these are. The air handlers are Lennox CBX32MV(3)and CBX32M (1) units, a total of four.

I have three questions:

1. First, can I use a MERV 12 filter in the air handlers?
2. Second, do I really need to change the UV lamps?
3. Third does $1800 sound high for the job?

Without doing a lot of research, I would say $1800 is probably a fair price. You can get a box of 6 17 X 26 X 4 MERV 12 pleated air filters for about $151.00 at Nordic Pure.

I’m not sure about the cost of the new UV lamps but I would expect them to be fairly expensive. Add labour and mark-up of parts and it sounds about right. If price is important you may be able to do better with another contractor.

I think MERV 9 filters will do an adequate job especially when used with UV sterilizers. If you are finding there is too much dust then you could try MERV 12 filters. They should work OK but may need to be changed more often. Higher MERV filters have a greater impact on air flow and if duct systems are undersized could cause problems. Certainly worth a try though.

UV lamps do need to be changed. The light intensity of UV lamps declines over time and they don’t perform as well. You would have to check with the manufacturer for their recommendations but yearly replacements are typical.