Introduction
The Serta Waterproof Heated Mattress Pad is designed to provide warmth and comfort. This mattress pad features a waterproof cotton blend material to protect your mattress from spills and accidents. It includes a controller with 10 heat settings and an adjustable 1-12 hour auto shut-off timer for safe and personalized use. The deep pocket design accommodates mattresses up to 17 inches thick. Queen and larger sizes are equipped with two controllers for dual-zone temperature control. This product is machine washable for easy care and is ETL certified for safety.

Image: Serta Waterproof Heated Mattress Pad on a bed, demonstrating its waterproof capability with a simulated spill and showing the dual controllers for individual temperature zones.
Setup Instructions
- Unpack: Carefully remove the heated mattress pad and controllers from the packaging.
- Placement: Lay the mattress pad flat on your mattress with the fitted skirt facing down. Ensure the heating wires are evenly distributed.
- Secure Fit: Pull the elasticized skirt over the corners and sides of your mattress. The deep pocket design is suitable for mattresses up to 17 inches thick, ensuring a snug fit.
- Connect Controllers: Locate the connection ports on the mattress pad. Firmly plug the controller(s) into the designated ports. For Queen and larger sizes, connect both controllers.
- Power Connection: Plug the power cord(s) from the controller(s) into a standard 120V AC electrical outlet. Ensure the cords are not pinched or covered by bedding.

Image: The Serta Heated Mattress Pad securely fitted onto a mattress, highlighting its 15-inch deep pocket and 360-degree elastic for a stable and tailored fit.
Operating Instructions
The Serta Heated Mattress Pad features an easy-to-use controller for personalized comfort.
- Power On/Off: Press the 'ON/OFF' button on the controller to activate or deactivate the heating function.
- Adjust Heat Settings: Use the '+' and '-' buttons to select your desired heat level from 1 to 10. Level 1 is the lowest heat, and Level 10 is the highest. The current setting will be displayed on the LCD screen.
- Set Auto Shut-Off Timer: Press the 'TIMER' button to cycle through the auto shut-off options, from 1 to 12 hours. The selected duration will be displayed. The pad will automatically turn off after the set time.
- Dual Control (Queen and Larger Sizes): For Queen and larger sizes, two independent controllers are provided. Each controller operates one side of the mattress pad, allowing individual temperature and timer settings for each user.
Important Safety Note: Do not leave the controller covered by bedding or other materials when in use to prevent overheating.

Image: Close-up view of two Serta Heated Mattress Pad controllers, illustrating the LCD display, 10 heat setting levels, and adjustable 1-12 hour auto shut-off timer. The image also indicates an 11ft controller cord for easy reach.
Maintenance
Proper care ensures the longevity and performance of your Serta Heated Mattress Pad. Always disconnect the power cord(s) from the wall outlet and the controller(s) from the mattress pad before cleaning.
Washing Instructions:
- Wash by hand or use a delicate cycle in a washing machine.
- Use cold water and minimal detergent.
- Remove immediately after the spin cycle to prevent creasing.
- Do not bleach.
Drying Instructions:
- Tumble dry on low or medium heat for 5 minutes.
- Remove damp bedding from the dryer, gently stretch, and hang to finish drying.
- Hang dry to preserve quality; do not use clothespins on the wired areas.
- Do not iron.
- Periodically check and straighten any bent or twisted wires to preserve shape and functionality.

Image: Detailed infographic illustrating the washing and drying process for the Serta Heated Mattress Pad, including instructions for hand wash/delicate cycle, cold water, minimal detergent, immediate removal after spin, tumble dry low/medium for 5 minutes, hang drying, and warnings against clothespins and ironing.
Troubleshooting
Refer to the following common issues and solutions:
- My light is blinking: Unplug and reconnect the controller to the mattress pad and the wall outlet. If the issue persists, contact customer support.
- Controller feels warm to the touch: It is normal for the control to feel warm. This indicates minimal electricity cycling through, which can make the controller warm.
- How should I store this at the end of the season? To prolong the life of your electric blanket, we recommend rolling the mattress rather than folding it. When storing, do not compress it or put anything on top of it. Doing so can cause damage to the wires which could affect functionality.
- I heard a pop and/or smell smoke: This is not a dangerous situation, but it can affect the functionality of the product. This most likely means that the fuse in the controller has blown for safety reasons and the product has been disabled. Please contact us for assistance.
- Can I plug it into a power strip, extension cord, or splitter? We do not recommend using a power strip, extension cord, or splitter with this product. Plug directly into a wall outlet.

Image: A visual representation of frequently asked questions and their answers regarding the Serta Heated Mattress Pad, including troubleshooting for blinking lights, warm controllers, storage recommendations, handling unusual sounds or smells, and advice against using power strips.
Specifications
| Feature | Detail |
|---|---|
| Brand | Serta |
| Model Name | Heated Mattress Pad |
| Model Number | ST55-0072 |
| Size | King (78"W x 80"L plus 15"D) |
| Fabric Type | 80% Polyester/ 20% Cotton |
| Special Feature | Washable, Waterproof |
| Product Care Instructions | Machine Wash |
| Water Resistance Level | Waterproof |
| Material | Polyester |
| Thread Count | 360 |
| Number of Items | 1 |
| Product Dimensions | 80 x 78 x 0.8 inches |
| Item Weight | 6.87 pounds |
| Included Components | 1 Heated Mattress Pad |
| Heat Settings | 10 Levels |
| Auto Shut-Off Timer | 1-12 hours (in 1-hour increments) |
| Power Cord Length | 6 ft |
| Controller Cord Length | 11 ft |
| Input Voltage | 120V / 60Hz |
Warranty and Support
This Serta Heated Mattress Pad comes with a 5-year limited warranty. For warranty claims, product support, or any questions not covered in this manual, please contact Serta customer service. Refer to the product packaging or the official Serta website for the most current contact information.
When contacting support, please have your model number (ST55-0072) and proof of purchase available.




