Does anyone have advice for a total novice (old but always had
baseboard heat) on the subject of the filters that go behind the
intake registers for a gas forced air furnace. For example:

Disposable versus Permanent?

Disposable 30-Day versus Disposable 90-Day?

How seriously to take the 30-Day and 90-Day limits?

MERV 11 versus MERV 8 versus MERV 4?

Permanent with polyester (claimed to be hard to wash) versus
without polyester (more expensive and claimed to be hard to wash)?

Suppliers that have good prices?

Thanks for any help.

On Mon, 17 Jan 2005 13:30:22 -0500, someone wrote:

Does anyone have advice for a total novice (old but always had
baseboard heat) on the subject of the filters that go behind the
intake registers for a gas forced air furnace. For example:

I have hot water baseboards!

Its been years since I lived in a hosue with a furnace. When I did, I
changed them once a heating season - and I bought whatever the local
HVAC supply shop sold. Never got into it as much as you did.


Reply to NG only - this e.mail address goes to a kill file.

A. Barnhard wrote:
Does anyone have advice for a total novice (old but always had
baseboard heat) on the subject of the filters that go behind the
intake registers for a gas forced air furnace. For example:

Disposable versus Permanent?

Disposable 30-Day versus Disposable 90-Day?

How seriously to take the 30-Day and 90-Day limits?

MERV 11 versus MERV 8 versus MERV 4?

Permanent with polyester (claimed to be hard to wash) versus
without polyester (more expensive and claimed to be hard to wash)?

Suppliers that have good prices?

Thanks for any help.

My heat pump has a permanent filter. The HVAC guy told me it's the
best available and that I should clean it every 30 days. I don't clean
anywhere near that often (probably more like every 90) but haven't had
any problems and it usually doesn't look very dirty when I do finally
get around to it.
I don't know if it has polyester or not. I clean it with a garden
hose, not difficult at all.

I am a total novice too, but I can tell you the answer to this question
has a lot more variables than you may have considered;

For example;

Do you have any allergy sufferers in the home?
How big is your furnace/how many square feet are you heating?
How often is the furnace run (ie what climate)?
Do you have any pets?
Is this new construction or old?
What is the age of your furnace and is it in good condition?
Does anyone in the house smoke?

MERV becomes a personal decision. Replacement frequency depends on how
dirty the filter becomes which is an issue of how much air is passed
through the filter and how dirty it is. Those day limits are for
comparison only.

Disposable versus permanent is really more of a personal issue. Can you
see yourself cleaning filters to save money?

A lot of these questions will only be answered through trial and error
on your part. Keeping a clean filter in place will extend the life of
your furnace and make it more efficient.

My only real advice, if you use disposable filters, always have an
extra one handy. If you're like me and have problems remembering to
change them, then it is better to have one when your thinking about it
than to put it off one more day.

dont get the $1 stuff and the $20 ones are overkill. and the reusables
ones are very unpractical unless you like the hasssle of wasting time
and energy washing a nasty spong once every couple of months.

the $5-10 filters clean the the air very well and the V shaped ribs
allow more surface area vs. the flat $1 filters so they flow much
better.

change them when you visualy see dust on the surface. change intervalls
really depends on usage. the 90day vs. 30day spec is really nothing but
BS.