For a change, this item is not a seasonal reminder; fires can happen anytime, as we all know, and if you have a sprinkler system, you certainly want to keep it in working order.
Here are some maintenance steps that you should undertake in every season.
1. Verify that all water shutoff valves are open and that the storage tank is full.
2. If the weather is cold and your system apparatus is in the attic, be sure that it is adequately insulated; icicles and frost are not going to put out any fires!
3. Perform a flow test regularly. Your system should have a clearly labeled flow-test valve; open it and let it flow to the outside for a minute or so. This should trigger your fire alarm, so be sure to notify your local fire company that you are doing a test.
4. Regularly check your sprinkler heads and cover plates and make certain that they have not been painted over; also check that they are not blocked by stacks of boxes or shelves.