Paul Franklin wrote:
On Thu, 06 Dec 2007 22:45:56 GMT, Phisherman wrote:

On Thu, 6 Dec 2007 11:46:51 -0800, "Bob F"
wrote:

"SteveB" wrote in message
...
"ransley" wrote

You realy cant put an hour or date on replacing them, If you have
pets, keep windows open and dont clean often it wont last long, maybe
3 months, and I have seen them nearly clean after 1 year.
EXACTLY. Some seasons when it's nice weather, one hardly turns on the HVAC.
Like you say, different people have different environments. Pet dander. Dust.
Lots of things. It is absolutely impossible to give any rule for changing
them EXCEPT change it when it's dirty.

It's like asking about how the weather will be tomorrow. It all depends on
where you live, don't it? It's not all the same.
The thermostat "monitors the number of hours on the air filter".

What part of that don't you understand?

Bob

How can a thermostat determine when a filter is dirty? I clean my
furnace filters (2 of them) once a month. You can put a reminder in
Outlook or other "calendar" software, then dismiss the reminder when
the cleaning is completed. I've done it that way for over 10 years.
The filter on the first floor gets much dirtier than the one on the
2nd floor. I have always heard to clean/replace monthly, and that's
what my neighbors do as well.

Filters like that Trion actually filter better as they get dirty
because the accumulated soil reduces the size of the pores in the
filter media. You are better off not changing it too often. Also, the
big pleated filters are quite expensive. The best way to determine
when it needs to be changed is to check the pressure drop across the
filter, and you can get devices to do this. One simple one is just a
whistle that starts making noise when the pressure drop across the
filter rises. On the other hand, if you don't change when it is truly
dirty, your airflow will be restricted too much and the furnace
overtemp sensor may shut the furnace down.

I'd set the thermostat timer to work out to about a month in prime
heating or cooling season and use its alarm as a reminder to *check*
the filter. If the pleats are uniformly gray and there is a
noticeable layer of dirt, then change it. Otherwise, reset the alarm
and check a month later when it goes off again.

My $0.02

Paul F.




Sounds like some kind of special filter system. I've googled and can't
find any info on this particular one. Can you give a description of how
this works and how it is different from a normal slab filter?