Furnace filter???

Reply

  #1  
Old 01-03-21, 02:26 PM
B
Member
Thread Starter
Join Date: Jan 2001
Location: United States
Posts: 53
Received 0 Votes on 0 Posts
Furnace filter???

We have a older furnace that was installed when the house was built in 1986. Would anybody know what the maximum Merv rating of a filter that I should use. I have read that some furnaces could be damaged if a too high of a Merv rated filter is used. Thanks!
 
  #2  
Old 01-03-21, 02:37 PM
Norm201's Avatar
Member
Join Date: Sep 2013
Location: United States
Posts: 9,713
Received 312 Votes on 281 Posts
Don't worry about the Merv rating. You want to protect the innards of the furnace, not the air quality you breath. Get pleated filter with as much surface area as possible. If you spend more than $10 a filter, you over spent.
 
  #3  
Old 01-03-21, 03:20 PM
R
Member
Join Date: Oct 2016
Posts: 2,056
Received 111 Votes on 105 Posts
Best to start with checking the heat rise and pressure drop across the furnace.
But the filter isnít there for indoor air quality. Itís there to protect the equipment from dust and debris.
Something to bring up, that a lot of my customers have asked. Is this something that you want to due because of covid?
 
  #4  
Old 01-03-21, 03:50 PM
B
Member
Thread Starter
Join Date: Jan 2001
Location: United States
Posts: 53
Received 0 Votes on 0 Posts
No, not really to do with the virus.. Just looking to buy some filters. I was using a MERV 9 for quite sometime and need to get more filters. 9 seems hard to find now so was wondering if the 10 would be ok, or if I should go with and 8 since it is such an old furnace.
 
  #5  
Old 01-03-21, 04:02 PM
R
Member
Join Date: Oct 2016
Posts: 2,056
Received 111 Votes on 105 Posts
What size is the furnace, and what size is the filter?
Id suggest going with 8.
 
  #6  
Old 01-03-21, 04:11 PM
B
Member
Thread Starter
Join Date: Jan 2001
Location: United States
Posts: 53
Received 0 Votes on 0 Posts
The filter size is a 16x20x1. As far as the furnace size.... I really don't know, or how I would find the size of it. My father used to handle all that before, now just me and my mother trying to figure it out...lol
 
  #7  
Old 01-03-21, 05:01 PM
T
Member
Join Date: Jan 2015
Location: USA
Posts: 751
Received 39 Votes on 37 Posts
I was using a MERV 9 for quite sometime and need to get more filters. 9 seems hard to find now so was wondering if the 10 would be ok, or if I should go with and 8 since it is such an old furnace.
Unless you live in a hospital lab, there's no need for a MERV 9 filter.

The purpose of a furnace filter is to protect the furnace. That being the case, it's unnecessary to get a filter above MERV 4. 16X20X1 is not an rare size. Look online (You know where.) and buy 6 or 12.

If you have a need for filtration for health reasons, I suggest getting an air purifier.
 
  #8  
Old 01-05-21, 08:53 PM
A
Member
Join Date: Mar 2010
Location: USA
Posts: 4,346
Received 114 Votes on 105 Posts
When in doubt buying pleated (zig zag folded) filters --- If they sell four grades, get the second lowest. If they sell three grades, get the lowest.

This avoids overloading the furnace blower due to air resistance in the filter.
 
Norm201 voted this post useful.
 

Thread Tools
Search this Thread
 
Ask a Question
Question Title:
Description:
Your question will be posted in: