Can anyone please tell me the best filter supplier for the Tranquility 27?

Thank you, it is almost time for replacement.

Easiest answer is your dealer.
The Climate Master filters are MERV 11 which is better than most you'll find at a discount on line.
If you would like to use a generic replacement, you can, but it will likely require more frequent replacement.
Worst case PM me and I'll ship them (<$50 ea.)
Good Luck,
Joe

6 flimsy filters @ $50 each from a local supply house came to me. They were replaced with the original filters at no extra cost.

Regards, Masoud

We've been buying the Accumulair Platinum MERV-11 "custom" (29 1/2" x 31 3/4" x 2") size from FiltersNow.com. Installer said really no need to go with the OEM Glassfloss filters - only difference is metal ribs which aren't needed in a vertical installation. They're $28 ea must buy case of 4 (or more), shipping only $7.99 for the case. We replace them every 3 months or more often if doing a lot of sheetrock/woodwork (last year).

BTW, the installer said they normally replace the filter at annual servicing with an Accumulair MERV-8, though today he brought me a MERV-8 and a MERV-11 he pulled from the same box, for this year and to swap out for the MERV-6 they mistakenly gave us last year. So check with your installer if they include one with service, and what rating is. They told us not to use MERV-13 since it would restrict airflow too much.

HTH

I've come to believe MERV-11 is a good compromise between good air cleaning and not overly restricting the air flow, assuming the filter area is plenty large for the air flow.

I use the same filter from the same source as AJ's Mom - seem to work well and last a long time, and no more than 0.05" wc measured across filter at low stage air flow.

Thanks for the info.  Just to make clear I ordered from Filters Now and I just want to make clear the dimentions for my unit are 29 1/2 x 35 3/4 x 2 .   Make sure you measure the existing filter in your unit to make sure.  These are custom filters and cannot be returned!

You might learn that a nominal (and stocked) 30x36x2 filter will actually fit