Replacement battery for stairmaster 4400pt - Stairmaster Exercise & Fitness

Replacement Parts for Fitness Exercise Equipment at SPORTSMITH

This sounds like you have a stuck key on your keypad. A new overlay keypad should correct your issue. The following link will show the some options for replacement.

Stairmaster Stepper 4400PT Parts Chain Pedal Arm Fastener SPORTSMITH net

This sounds typical of a faulty keypad. It sounds like you have a stuck key. The normal step to alleviate this is to replace the overlay and keypad. Replacement Parts for Fitness Exercise Equipment at SPORTSMITH

Stairmaster Stepper 4400PT Parts Chain Pedal Arm Fastener SPORTSMITH net

Stairmaster Stepper 4400PT Parts Chain Pedal Arm Fastener SPORTSMITH net

Click on the manuals tab in the middle of the screen. You will have access to the owners and service manuals.

Resistance Troubleshooting Video for Stairmaster Stepper 4400CL 4600CL...

Power Supply Kit with Plastic Output Connector Domestic Stairmaster...

We offer several different options for the 4400PT.

The instructions and more information on your machine can be found in the owners manual.
http://www.sportsmith.net/images/product_support%5Cstairmaster%5CManuals%5C42-44-4600PT-CL_Red-LED_Display_Freeclimber_Manual.pdf

Stairmaster Stepper 4400PT Parts Chain Pedal Arm Fastener SPORTSMITH net

I would suggest checking the voltage output from your power supply. You should be getting between 12-19 volts dc. Repair Parts for Stairmaster Equipment Batteries Springs Belts Chains...

Video about Multimeter Testing

Replacement Parts for Fitness Exercise Equipment at SPORTSMITH

You can take the covers off and see if it is indeed the chain that is slipping, but in most cases, the drive sprocket is actually what is failing. The following link will take you the item that should rectify your issue.

Drive Hub for Stairmaster Steppers 4000PT 4400CL 4600CL 4400PT 4600PT...

Replacement Parts for Fitness Exercise Equipment at SPORTSMITH

This sounds like either an alternator issue or the brushes in the alternator. I am going to attach some troubleshooting videos.
Stairmaster Stepper 4400PT Parts Chain Pedal Arm Fastener SPORTSMITH net

This could be the hub assembly slipping I would replace this assembly and the pedal chains call National Gym Supply @ 800-496-7278 and get pricing for the hub assembly and step chain ( L & R )