Whole House Air Filters?

As many of you know, a member of my family suffers from severe asthma that is greatly aggravated by particulates.  I am considering having an hvac system installed that includes a whole house air filter.

I was wondering whether anyone has experience using these systems and/or recommendations when it comes to brands and how to avoid potential pitfalls. 

One of my particular concerns is with getting a system that will filter out wood smoke.  While my immediate neighbors are very considerate in not using wood burning fire pits, they seem to be everywhere in  the community at large and the smoke is a reliable trigger for attacks.

I have forced air heating and cooling. The system has a media filter. I'm using filters rated at MERV 11. My filters last about eight months.

https://www.amazon.com/X6673-Lennox-20x25x5-Filter-Media/dp/B008D7URTG/ref=sr_1_fkmr3_1

MERV Rating Chart

Klinker said:
  I am considering having an hvac system installed that includes a whole house air filter.

 I’d have to ask what you mean by an hvac system that includes a whole house air filter.   

I have no idea how informed you are with mechanical systems so I will make a few points and we can go from there.  

If you’re talking about a whole house system you’re talking about a centrally located system with ductwork that runs throughout the house.   If you’ve heard of mini splits that are common in this area, these would not provide what you are seeking.  The whole house system does have a filter but it is there mainly to keep debris out of the mechanical system.   Now some will go buy an upgraded filter to put in the system, but that is of questionble value.   The reason for this is that a whole house system typically has only one return- the vent that sucks the air in the house back to the system.  If you’re in a second floor bedroom with the door closed, the return downstairs really can’t draw airborne particulates from that room.   

Go ahead and do some research but my advice would be to address the air quality issue separately from HVAC if there are health concerns in the balance.   With all the fires in CA lately there was an article (NYT I think) that had a lot of good advice about portable air filtration systems.

Red_Barchetta said:

I have no idea how informed you are with mechanical systems so I will make a few points and we can go from there.  

I believe the technical term is "not at all".

Red_Barchetta said:

The reason for this is that a whole house system typically has only one return- the vent that sucks the air in the house back to the system.  If you’re in a second floor bedroom with the door closed, the return downstairs really can’t draw airborne particulates from that room.   

That does sound intuitive.  We are getting a little desperate.  We have HEPA towers throughout the house but on smokey nights they just don't keep up.  Our windows are Pellas and they have a fair seal but I think the house itself is just drafty.

I have a return in every room. Air gets pushed into the room, gets returned, passed through filter. A continual filtering.

https://www.jlconline.com/how-to/hvac/choosing-a-whole-house-ventilation-strategy_o

Klinker said:

Red_Barchetta said:

I have no idea how informed you are with mechanical systems so I will make a few points and we can go from there.  

I believe the technical term is "not at all".

Red_Barchetta said:

The reason for this is that a whole house system typically has only one return- the vent that sucks the air in the house back to the system.  If you’re in a second floor bedroom with the door closed, the return downstairs really can’t draw airborne particulates from that room.   

That does sound intuitive.  We are getting a little desperate.  We have HEPA towers throughout the house but on smokey nights they just don't keep up.  Our windows are Pellas and they have a fair seal but I think the house itself is just drafty.

 Have you had your house insulated?  It won't stop all air infiltration but it will significantly reduce it.