We realize it is still too early to remove the cover from the pool and start using it, but it is never too early to plan for opening a swimming pool.
If you have a sand filter, when was the last time you either changed your sand or cleaned the sand? As you go through a swimming pool season, suntan lotion, oils from your body, peeling skin, etc. all go into your filter and could affect the operation of the sand filter.
The sand should be cleaned at least once a year and how often you change the sand will depend on how active you are in using your pool, how many people use it daily, and how well you keep the pool chemicals balanced. You should try to change the sand at least once every three to five years depending on pool usage. If you have not changed the sand within five years, a good time to do it would be before you remove the pool cover.
Check the o-rings on the pump drain plugs. When was the last time you changed them? If they are worn, this will cause air to get into the circulation system and you might have a hard time priming the pump or getting a good flow of water into the pool. You should replace them each season. Also check the drain plug on your filter to see if it has an o-ring.
Your sand filter has a multi-port valve. Is the handle hard to turn? If it is, you might be having some problems with your spoke gasket. Fit it now while you still have plenty of time. When you turn the multi-port valve handle, does it loosely fit back into one of the listed functions? If so, you should replace the spring. Make opening your pool a little bit easier by addressing these items soon.