A sliding glass door can act as a means of enjoying the outdoors, by creating a room with a view. It can also enhance natural light and ventilation. At the same time, a poorly operating sliding glass door can be dangerous and can require great physical strength to open and close.

Unfortunately, even with good maintenance, some sliding patio doors are just plain heavy and bulky, making them almost impossible to slide in the opening. This condition is particularly true of early insulated or double-pane models. Energy efficiency improved, but operation became difficult due to added weight on over-stressed rollers.

Today's high-end sliding patio doors embrace the best that technology has to offer and can be operated with the touch of a finger. Even most of today's production models are very different from their difficult-to-operate predecessors.

If you're tired of your sliding glass door bumping and grinding its way open and closed, there are steps that you can take to make it easier to operate.

A sliding glass door operates much like a train. Rollers fastened to the underside of the movable panel are designed to glide along a track on top of the threshold. The rollers are made of steel and plastic, and are available with or without ball bearings. The track is aluminum, vinyl or stainless steel.

There are several factors that can cause your sliding patio door to operate sluggishly. Ironically, a couple of the most common reasons for poor operation are dirt and grime buildup on the rollers and-or track. The best way to solve this problem is by regularly cleaning and lubricating the track and rollers.

Although removal of the sliding panel is not necessary for regular maintenance, we recommend it for this first major go-round. To remove the door, open it to the center of the opening and lift up and pull outward from the bottom. It's a good idea to have a couple of sawhorses handy to lay the door upon while it is being worked on.

Use a vacuum with a narrow attachment to remove loose surface debris in the track and at the underside of the door frame—especially around the rollers. Next, use a soapy solution or general purpose cleaner to clean and degrease the track and rollers. An old toothbrush works well to get into hard-to-get-at places. Rinse thoroughly with fresh water and dry the area completely. A small air compressor with a spray nozzle works well for removing debris and drying damp parts after cleaning.

When the door's out of the opening is an opportune time to inspect the condition of the rollers and track. The rollers should be in good condition (smooth and free of dents or chips) and spin freely. Anything less might mean that the rollers need additional cleaning and lubrication or require replacement. Remove gunk buildup on the rollers by soaking them in a degreasing solvent. Keep in mind that harsh solvents could damage plastic rollers. Lubricate rollers with a greaseless silicone that will prevent future dirt buildup. Whenever possible, use a lubricant specified by the manufacturer or installing dealer.

If, after cleaning and lubrication, the rollers still are not operating smoothly, remove them and install new replacement rollers. Replacement rollers can be found at most hardware stores or home centers. You'll have better luck finding a replacement if you know the brand of door. Also, never head out to the store without taking along one of the existing rollers to make a match.

There are replacement hardware companies such as Blaine Window Hardware, Inc. (www.blainewindow.com or 1-(800)-678-1919) that specialize in hard-to-find and current replacement window and door parts.

A damaged track or "runner" is another primary reason for poor door operation. A dragging door wears down the top surface of the runner making it impossible for even the best of rollers to operate properly. Depending on its condition, the runner can be capped or replaced with a new plastic or stainless steel model. The cap style fits over the existing runner while the replacement unit requires the damaged runner to be removed and covered by a new plate-mounted runner. In either case, the door will operate like new.

Reinstall the sliding panel in the same way it was removed. Insert the top of the panel into the top track and lift the door onto the track. Move the door open and closed to test the operation. Check to ensure that the bottom of the door frame is not dragging on the track. If it drags, use a screwdriver to adjust the rollers down (and the door up) so that the door doesn't come into contact with the track. Only the rollers should touch the track.

Worn weather-stripping can also be the cause of a poorly operating door. Most weather-stripping can also be replaced.