My 2 cents... (Apologies for running on, but at least I tried to keep it sort, lol)
What do you think you are accomplishing? That filter is only rated for 150 microns which is a rather course sediment filter. A rating of 5 microns is better for sediment. Definitely won't be removing pathogens of any kind at that micron rating and any that might be present in the water will sail right through when in use.
If you are thinking you are doing it to prevent the growth of any pathogens that might have collected on the filter to prevent anything from getting through, freezing won't kill them all. Freezing may kill some, some will stop multiplying and remain, others will survive and some will come back to life after the temp. rises again. If you keep a filter in a cold environment, you'll at least slow down the growth of pathogens, which is good and a filter with KDF or silver helps too.
Freezing can damage filters. Removing a filter from high ambient temperatures will help, but just put it in the fridge. "Decent" filters that have manufacturers specs cover lots of details including min. and max temps. Many are rated max. 30 degrees C or say 40C, and min. around 4C.
If you're concerned about removing micro-organisms, bacteria, etc. get a filter rated at 1 micron
absoluterating (or better) and not a "nominal) rating (HUGE difference). I know there are exterior inline filters rated at 1 micron, but I don't think they have an absolute rating, but at least be a lot better than 150 microns.
If you want to have some decent filtration, lose the exterior inline filter. They typically have a low flow rate too like 1 gpm. Rated life is typically low as well and life is rated in either total gallons or time, and sometimes both. Removing/reducing chlorine before it gets inside an RV is not a good idea. A filter does not remove 100% of harmful pathogens. If you remove chlorine and you RV sits for extended periods, pathogens can multiply inside the water system in your RV. If you really don't like the taste or smell, use a "point of use" filter. If you have a filter with silver or KDF in it, that does not kill and prevent pathogens from passing through the filter, it's there to prevent them from multiplying in/on the filter media and these are called bacteriostatic.
In seasonal campgrounds, chlorine residual levels can be very low or non-existent after a long winter with no park users. Pathogens can grow and flourish in stagnant distribution lines. If there happens to be some chlorine remaining, I think you are better off leaving what is remaining in your system. Some is better than none.
Some pathogens such as Giardia and Cryptosporidium are chlorine resistant because they are "hard shell" cysts. Only a filter with a 1 or better absolute micron rating will effectively remove them. If you are hooked up to a public "city water" system, usually no worries, but if you are somewhere that has surface water sources that draw their water from lakes, creeks, etc., it can be something to think about.
Look for a filter that is NSF certified otherwise a manufacturer can make exaggerated claims (and they do). The TastePure filter has almost nothing for specs. If you want an exterior filter, look at ones that use cartridges that fit a whole house size housing, either the slimline or the 2.5" dia. ones (both 10" tall). Look at filter specs closely to see what the performance really is. This is simply an example, but this vendor has full specs on filters and this gives an idea of tings you want to see on a filter spec sheet:
Floplus 10 I actually bought a couple of these in the beginning before going with someone more elaborate (make me an offer!). I'd consider a sediment pre-filter and then a low micron rated filter after it. You can buy an exterior dual setup that sits on a stand.
If it's just the water in your kitchen that is the concern, consider a quality under-the-counter multi-stage filter like the
Watts Premier 531130 UF-3. This incorporates an ultrafiltration UF filter that filters down to 0.2 microns and does a far better job at removing bacteria and other pathogens and will even remove some viruses. It also says it will remove VOCs, lead and MTBE. I'd also use a sediment cartridge outside of probably a 5 micron rating to keep sediment out of the rest of your system.
When you use low micron rating filters, you need better control of pressure and better flow rate. I go to something like a Watts 263A regulator or at least the 560 series and don't use the basic exterior inline ones.
If looking at just a sediment filter, bacteria will thrive in some filter media like the pleated paper ones but a string-wound polyester one will not promote bacterial growth. If looking more closely at filter specs, some filters have poor flow rates and some are very good. A low flow rate regulator + low flow pre-filter + low filter final stage filter(s) = even lower flow rate. Choose your filters wisely.
Rv-ing presents it's own unique circumstance when it comes to water quality, one of which is the intermittent use of filters. For week-enders who have filters mounted inside their camper, it may be a judgement call as to how warm/hot it may get inside your unit between trips and for how long. For exterior type filters, in warmer climates, I would at the least take in indoors into a cooler place or put it in a fridge. If there's space in your camper's fridge between trips and you keep it running while parked, just put the complete filter in the fridge. Another unique circumstance can be for those doing a lot of travelling around the country where water quality can vary a lot and you won't know what's in it and you'd want to pay more attention to the filter type and specs you are using and keeping the temps down on it (them) when not in use.
Back on temp..... I contacted one filter manufacturer on a filter I was looking at with a max rating of 30C (86F) degrees and they said leaving it in a 30C+ ambient for a few days is okay, but beyond that it would be a good idea to store in a fridge. So I would recommend storing it (them) in a fridge and not a freezer. In an RV, depending on the filter cartridge and it's specs, you should replace them annually. Some cartridges like a Doulton ceramic, can be cleaned and re-used up to 50 times for example (has silver in it) and some say replace every 3 years but I'd store them in a cool place or fridge over the non-use winter period. Sediment only cartridges are quite inexpensive and I would just toss it out at the end of the season.
