My Roper dryer, model RED4100sq0, will tumble but not dry. Also, the timer does not run so the dryer runs continously after starting. There is no heat from the element. Both of these problems started at the same time.

bad timer moter. replace timer

How old is this machine and are the clothes dry and still running.? Is there a moisture sensor on this model ? Does the timer indicator move around the dial, if not timer is bad.

Your machine may have a feature called wrinkle guard or wrinkle shield, which basically keeps tumbling the clothes without heat to prevent wrinkles from setting in. Turn that feature off and see if that does the trick.

Is it gas or elec?
Have you checked the breakers?
Does the outlet have power?
Model# ?
Try setting timer in a different cycle.
Make sure door is completely closed.
Push door switch in manually does it click?
Please update lat me know what else I can do to help.
Ken

If you are experiencing longer dry times and/or poor drying efficiency, the following link can give you some tihings to check before assuming there is a malfunction with your dryer:

http://www.fixya.com/support/r3578821-dryer_takes_too_long_to_dry

The number one cause of dryer heat related problems is poor exhaust ventilation. If not vented properly, a dryer will not dry efficiently, will take longer than required to dry, and will cause the heating circuits to overheat to the point of failure. The dryer will actually seem hotter as the heating circuits begin to overheat. This is also the source of many fire hazards if not resolved. Read through the link provided and review some of the potential causes. Hopefully, this may save you a service call. If you check everything and still have poor heating issues, please let me know. You may have an internal bias or hi-limit thermostat malfunctioning.

Have you checked the entire duct run. When dryer vents should feel like a hair dryer on high blowing outside

 If your unit has a standing pilot, is the pilot lit?  If not, push the Basso control button and light it according to the instruction sticker.
Next, the main thing you should suspect is the capillary tube.  This thin tube runs from a hollow bolt on the gas control to the gas burner. If defective, it will not allow the unit to light off further.  Remove the tube, take it to the hardware store and get a replacement and install.  If these two items don't fix the unit, get professional help.

Dryer will run forever if it doesnt heat up, Dryer has to heat up and thermostat has to get hot and open to start the timer. Odds are rally great, it is your heating element.

hi i think the motor is unstable so the drying ability is decresing check and service it

Sounds like a timer problem let me know I can help you..