Kirby recommend you change the bags on their vacuums every month, unless your home is larger than 2000 square feet, you have recently laid new carpets or you have pets, in which case you should change it every 2 to 3 weeks.
monthly
A dust filter should be changed as often as the manufacturer suggests. This is usually every three months or so for a Dyson vacuum cleaner although more often would be good if a very dusty environment is being cleaned.
How often should you change the fuel filter?
Whe it needs it
There is no strict rules about that. You need to inspect hoses periodically. But when you have a car which is 10 years old you might need to change all vacuum hoses around the engine.
as often as needed
You should change your oil every 3,000 miles. If you drive your car rough, then you should change it more often.
once to twice a week is the general time gap that people would go by to vacuum their floors.
everyday
How often should you change water pump in a boat
Every week
You should change them after every feeding because they should be washed after every feeding.