[Altavia]

Originally Posted by Golfer222

An HVAC tech up north told me merv 11 is too restrictive and could damage the unit-

What MERV Filter Do I Need | Air Filter MERV Rating | Carrier — Carrier @ Home.


What Level MERV Filter Do I Need?

Let’s talk briefly about Carrier recommended MERV ratings. Earlier, we mentioned that a MERV rating between 8 and 10 is a good option, but if you are looking for an even higher efficiency, you might consider purchasing air filters with a 13 MERV rating.

Remember that your HVAC unit should be up to the task, so if you are considering higher MERV rating that can filter out some of the smallest particles, we recommend that you speak to a local Carrier expert to ensure that your system is powerful enough to force air through these very effective filters.

[Golfer222]

yes- that is my concern

may go with an 8 and a Swiffer

[Maker]

My filter is a non standard size. Found I can order any custom size I want (by the fraction of an inch) at filtersfast=dot=com Highly recommended. Measure the old one and buy an exact same size.

MERV 8 minimum, MERV 11 better. MERV 13 even better, but older systems may not have the capability to push sufficient air through it because it is more restrictive.

[retiredguy123]

I buy filters from Amazon using the "Filterbuy" brand. For 2-bedroom houses, the 16 x 20 x 4 filters are needed and available. Filterbuy is an excellent USA company. The Filterbuy brand is not available for 3-bedroom houses which use the 19 x 20 x 4 filters. But, you can go to their website and order a custom size filter. I have been using the Merv 11 filters for several years and they perform better than the Merv 8 type. If you use the "Filtrete" filters available at the local stores, they will fit you unit, but you may be limited to Merv 8.

[metoo21]

The filter that was in my unit when I bought the house new was 19.13x19.88x4.25 i.e. 19 X 20 X 4

Filterbuy has it listed as 19x20x5 but it is actually 19.13x19.88x4.25

MERV 8

MERV 11

[Topspinmo]

Originally Posted by Bill14564

A few thoughts:

- I haven't heard of sensors in the blower unit that would shut off the outside unit in the case of low air flow. Plus, if those sensors did exist it makes sense that they would shut off the blower unit too.

- If the filter is dirty enough to block the airflow sufficiently to be a problem then it needed to be changed long ago

- Could it have been cycling the breakers that solved the problem; did you try putting the filter back in? I had a similar problem during the cooling season. Blower fan was running, outside unit was making a soft humming sound, but fan was not running. I cycled the breakers just to see if it would help and it did. (I later replaced the capacitor just in case)

- Amazon has filters in that size. MERV 8 and MERV 11 are typical.

Also if you go higher merv rating it could affect air flow. Especially if it’s low to begin with? My new unit had 6” suitcase filter. When heat finely came on for first time it was only blowing 290 cu feet per minute at closest vent and furthest vent was 195.

I asked the installer to make sure air flow was enough, he said they set them to factory specs, but was not factory filter installed.

After studying the wiring semantic removed (medium)orange wire from spare and plugged in where (low) blue wire was on heat. Now I have 820 to 690 cubic feet per minute. Yes I have my Chinese mini Anumometer to check it. Also if don’t get enough air flow over the heat exchanger it can damage it.

My old unit had DIP switches that would change fan speed.

[rsmurano]

Check the outside breaker next to the unit. I had a technician forget to put that breaker back in after servicing the outside unit. That’s all it was

[retiredguy123]

Note that official Carrier HVAC filters can be purchased with MERV ratings of 8, 10, and 13. Just because your new unit came with a MERV 8 filter doesn't mean that you cannot upgrade to a higher MERV rating. I have not been able to find anything from Carrier websites that says otherwise.

[hvac877]

You will need to have a service company check the controls outside. If nothing is running on the condenser it could be a burnt wire on the main power 240 volt side of the single pole contactor. The compressor contactor coil may have burnt out and be the problem. or the low voltage that pulls the contactor in may have a broken wire. When I was servicing in The Villages I found on a few occasions the low voltage wire cut and or broken because of the landscaper weed wacker cutting the wires causing the condenser not to come on. It is best to keep the area around the outside unit clear to keep them away from it.

[retiredguy123]

Originally Posted by hvac877

You will need to have a service company check the controls outside. If nothing is running on the condenser it could be a burnt wire on the main power 240 volt side of the single pole contactor. The compressor contactor coil may have burnt out and be the problem. or the low voltage that pulls the contactor in may have a broken wire. When I was servicing in The Villages I found on a few occasions the low voltage wire cut and or broken because of the landscaper weed wacker cutting the wires causing the condenser not to come on. It is best to keep the area around the outside unit clear to keep them away from it.

See Post No. 10. Apparently, the issue has been resolved.

[wsachs]

Originally Posted by retiredguy123

In my opinion, that tech is wrong. I get plenty of air flow with Merv 11 filters.

I just had a new Lennox AC unit installed and it came with a MERV 13. Lots of airflow and very quiet.

[bonrich]

Originally Posted by Golfer222

May have been a filter issue- I pulled the filter and it is now working- trying to find a 19 x 20 x 4 -tough to find also no mention of the MERV on this one- what is typical

Home Depot has the filter size you are looking for. They are a Merv 8.

[DStahulK]

Originally Posted by Golfer222

May have been a filter issue- I pulled the filter and it is now working- trying to find a 19 x 20 x 4 -tough to find also no mention of the MERV on this one- what is typical

I order filters from Discountfilters.com for our furnace. They fit perfectly.

[Wondering]

Search You Tube videos.

[Cliff Fr]

Originally Posted by Golfer222

Heat pump outside unit not coming on. Air coming out of vent is 66 degrees even though thermostat is set at 74. Thinking it may be a breaker issue,. Garage main panel breaker is fine. Are there other breakers in the chain and if so where?

It's possible that the unit was in defrost mode when you checked it. It's also possible that if you changed the setting on the thermostat too many times in close succession the time delay for the compressor kept it from coming on (more likely)