Here is the filter condition. 3.5month didn't takeout for clean. Lazy mode + busy schedule.
Closeup on the coil after takeout the dirty filter.
After detergent wash the filter and vacuum the coil.
So do I need to pay extra for an additional filter every month?
Just saw this post. Good read.
If it's RM29 + can only use for maximum of 2 months + single 30x60cm sheet ...
RM29 X (12/2) months = RM174/year (6 packs needed)
Full service for non-inverter R22 units are about that price?
Unless you plan to re-wash that piece for a year / planning to use this for years & skip service for years (except gas top-up) then, it could be economical.
If intention is to keep some dust out of the A/C, use those available at Daiso for RM5... (40x80cm x 2pcs).
Since it's 2pcs, you only need 3 packs which is RM15 a year.
Of course, if you just want the best filtration, 3M is for you...
My advice:
Only problem with these filters, 3M or not, they are a blockage to the airflow, it's the same as having a small layer of dust on the filter itself.
My non-inverter Daikin unit has a
longer compressor ON cycle with the filters (15-18minutes ON / 17-20min OFF)
Without filter its 7-10min ON / 15min-20min OFF. It may affect your electricity bill. Yes. I painstakingly measured it over a few nights.
My unit is oversized for my room, i have about 3000 to 4000BTU of extra capacity. So, i had short cycle problems.
Compressors need about 10mins to get to maximum efficiency, plus they shouldn't cycle on/off too often, it wears down the compressor & it pulls a lot of current each time it starts. Also, 7-10mins is too short for it to remove humidity (you still sweat when working out with the a/c on). Hence applying the filter benefited me as the recommended ON cycle is just about that. It worked out perfectly for me.
But, if your unit is already at it's optimum cycle (about 20min ON), putting the filter may give you something like 30-40min ON.
This may raise your bill. For inverters that will have no on/off cycles, the reduced airflow may cause the system to run in a higher power setting for the compressor & fan. Put that into consideration ya... as this means that eventhough you may skip full cleaning on the indoor coil or entire unit for a year or 2, the cost of the filter + your electricity bill may outweigh the benefit altogether.
Manufacturers aren't dumb, they spend a lot on R&D & there is a reason why the OEM filters are thin & not dense. They give you best airflow, best air-throw, best cooling, in the optimum operating time, with the best energy consumption (if you follow proper BTU/sq.ft sizing guidelines), with lesser noise too. In less diplomatic words, they would rather have you service their air cond at proper intervals, than you complain of cooling, energy, noise issues.
Everyone's application will be different, test it, if it does nothing serious to your wallet, or if it helps your wallet go ahead & use them. If it does the opposite (it may!!), simply cleaning & servicing regularly will be more cost effective and healthy for the a/c. If cost isnt a concern, just plaster them on and dont bother...