With some simple cleaning and routine care, you can keep your Andersen® Combination Unit looking great and working well for years.

How to Clean and Maintain Your Combination Unit

An Andersen® Combination Unit is a self-storing storm window with an insect screen, combined into one convenient system that installs on the exterior side of 200 Series Narroline and most 400 Series double-hung windows.

A Double-Hung Window Combination Unit

When to Use This Article

We recommend following the instructions in this article to check the condition of your Andersen® Combination Unit and to clean it at least once a year. If you live in a coastal, industrial, or agricultural area with higher levels of airborne materials like dirt, dust, smoke, and salt spray, we recommend following these cleaning instructions at least every three (3) months. Follow the painting instructions as needed. 

This Article Will Help You:

• Clean your combination unit's insect screen, frame, and sill.
• Maintain your combination unit.

Tools and Supplies Needed

• Two (2) soft cleaning cloths or soft-bristle brush
• Soft-bristle brush
• Mild soapy water
• Vacuum

If you plan to touch up or paint your combination unit, you may need these additional supplies:

• One (1) soft cleaning cloth
• Steel wool or 240-grit sandpaper
• Surface conditioner or acetone
• Andersen® touch-up paint
• Fast-dry alkyd primer
• High-quality oil or water-based paint
• Paint stripper
• Paint brush

Follow the paint your combination unit instructions below.

Let's Get Started

Clean Your Combination Unit Insect Screen and Frame

Cleaning your combination unit's screen and frame can be done in a few quick steps to clean both the combination unit and the window sill it sits on.

1. Wipe away any debris on the insect screen mesh or combination unit frame.
2. Use mild soapy water and a soft cleaning cloth, or soft-bristle brush, to clean the insect screen mesh and combination unit frame.
3. Rinse off any soap residue from the insect screen and combination unit frame with fresh water.

Note: Be careful not to scrub the insect screen mesh too hard, as it could damage it.

See Clean Glass, Aluminum, Vinyl, Fibrex®, and Fiberglass Surfaces on Andersen® Windows and Doors for more details on cleaning your window glass.

Clean Combination Unit Sill

The combination unit sits in the window sill, which can also be cleaned when the unit or window panes are removed. Depending on the type of unit you have, follow Steps A and B for double-hung unit removal, or Steps C and D for gliding unit removal. Then proceed to Steps 2 and 3.

1. Remove the combination unit panels from the frame.

2. Vacuum or wipe away any debris you see in the sill.
3. Reinstall panels.

Maintain Your Combination Unit

Controlling condensation and checking the condition of your unit to see if it needs any paint touch-ups are some additional maintenance steps that can be taken to ensure optimum performance.

Control Condensation

Condensation between the window unit and the combination unit may indicate that the combination unit is functioning as intended.

Windows are typically the coolest areas of interior walls. When the warm room temperature air comes in contact with the glass surface, the air is cooled, and if there is enough moisture in the air, the dew point will be reached, and the water in the air will condense. For additional tips on controlling condensation, see Condensation on the Exterior of Window or Patio Door Glass.

Paint Your Combination Unit

Before applying paint to the aluminum insect screen frame and/or combination unit frame, inspect it and determine whether the paint is faded or cracked.

• If the paint is faded, but only a small area requires care, follow the touch-up paint instructions below.
• If the paint is faded, and a large area requires care, follow the painting large areas instructions below.
• If the paint is cracked, follow the painting cracked paint instructions below.

Touch Up Paint

1. Buff the combination unit frame with steel wool or 240-grit sandpaper until the surface is dull.
2. Remove any dust particles with a soft, dry cloth.
3. Clean the frame by wiping.
4. Apply touch-up paint.

See Andersen® touch-up paint to purchase the correct paint.

Painting Large Areas

1. Buff with 200-grit sandpaper until the surface is dull.
2. Remove any dust particles with a soft, dry cloth.
3. Clean the frame by wiping it with a surface conditioner* or acetone.*
4. Prime the frame's surface with a fast-dry alkyd primer* in a neutral color.
5. When the primer is dry, remove the operating panel and apply a high-quality oil or water-based paint.*

*Always read and follow the manufacturer's recommendations for proper use.

Painting Cracked Paint

1. Strip the paint off the frame using a paint stripper or sandpaper.
2. Remove any dust particles with a soft, dry cloth.
3. Clean the frame by wiping it with a surface conditioner* or acetone.*
4. Prime the frame's surface with a fast-dry alkyd primer* in a neutral color.
5. When the primer is dry, remove the operating panel and apply a high-quality oil or water-based paint.*

*Always read and follow the manufacturer's recommendations for proper use.

Need Parts?

If you need to order replacement combination units, see Replacement Combination Units. Or if you're unsure which replacement units to order, Contact Andersen® Windows and Doors.

Related Articles

To identify the parts of your double-hung window combination unit, see Identifying Components on a Double-Hung Combination Unit.

To identify the parts of your gliding window combination unit, see Identifying Components of a Gliding Window Combination Unit.

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