1.   A clogged filter will obstruct proper air circulation and impede operating efficiency.

2.   A clogged filter will not shut down the system, but it will cut efficiency and raise heating bills.

3.   The narrow line used to periodically jettison the fluid into space has been blocked since midweek by what engineers believe is a clogged filter.

4.   Ships which receive contaminated fuel can experience problems such as clogged filters and jammed fuel pumps.

5.   The city never had to shut off its water system, although clogged filters led to low pressure that caused thousands to be without water.

6.   The two tried to bypass the clogged filter so waste water in the main storage tank could be dumped.