Google your kenmore model and no heat in dryer and you will find your answer.

billp - Thanks for the suggestion. I did that but didn't come up with much info. specific to my model (76972).
One possibility suggested was the ignitor, but since I do have a very small amount of heat, I don't think that could be the problem. Another possibility is the heating element, although I wonder why I would be having less heat after having the vent cleaned than I did before. If it is the heating element, I would still like to know whether this is an expensive repair.
Hope others who had similar problems will share their experience.

76972 is not a full model number. The full model number is longer than that, starts with three digits, a period, and up to 8 more digits. Example: 110.20907990

A gas dryer does not have a heating element, it has a gas burner. The problem could be the gas valve or temperature thermistor. Post your full model number here and perhaps you'll get further assistance.

Thank you for the help, Dadoes
The full model number is:
110.76972502

This is a Whirlpool-sourced Kenmore model. Here's a link to a Tech Sheet at Whirlpool's service site which outlines some tests & service info for your model.
110.76972502 - 8545909

I don't have direct experience with gas dryers, but the only appreciable difference between gas and electric is a gas valve vs. an electric heating element. I'd suggest checking the thermistor for proper temp & resistance readings, the gas valve, and the electronic control board. See Page 6 of the Tech Sheet.

You've already contacted a service company ... but for your reference, parts can be found at various online sources such as SearsPartsDirect.com, PartsTap.com, AppliancePartsPros.com and RepairClinic.com.

sounds like a bad Gas Valve Coil.
They get sluggish when they get old.
common problem

$ 20 set

I agree with Regus, If I was the tech coming to your house I would have the coils in my hand when I knocked on your door.
Depending on usage they are generally good for 5 to 8 years. Many times when they start to fail they will allow the gas to come on once and then not work again until they cool off. This may be why you had low heat.
They're easy to change and usually only a 15 to 20 minute job for most dryers.

Thank you all for taking the time to offer suggestions. I appreciate all of your help.
I wanted to post a follow-up, just to let you know how things played out. The repairman came this morning and agreed that it was probably the gas valve coil. He replaced it, but the problem persisted. He worked very hard to diagnose the problem and spent a lot of time on the phone talking to coworkers getting their opinions about what could be causing the symptoms he was noticing. In the end, he came to the conclusion that there was still some sort of obstruction in the dryer vent, as the dryer heated fine when unhooked from the vent but would not heat as soon as he hooked it back up.
So - I put in another call to the guy who had "cleaned" the dryer vent two days ago. He came out a few hours later and recleaned it and was able to push out a fairly large clump of lint that he missed the first time (don't ask me how...) That must have been the problem, because the dryer is now heating well and works fine.

Even though I stated I would have carried the coils with me when I knocked on the door it amazes me that the tech put them in with-out first making sure the originals were bad. I mean there are just certain things you do before replacing parts and in this case checking for a good or lazy flame verifys if the vent is clear. This is really simple. Lazy flame with vent connected, remove vent test again if good flame you have a vent problem. Period !
Hopefully they didn't charge you for the part or more than 20 minutes labor for their poor quality of service.
The fact he had to talk to co-workers to determine a basic issue...

Jakvis - I appreciate your perspective on this. Now that I have had a couple of days to reflect, I agree that the technician could not have been too experienced. (The company got great feedback on AngiesList, but this guy may have been the exception.) I did mention the possibiity of bad coils as I explained the problem to him, so maybe I am partly to blame. But I would think he would have checked the flame with/without vent earlier in the service call. He was here close to 90 minutes, talking to a co-worker about the possibility of a bad motor, ignitor, etc. before he decided to check the vent. When he determined that it was a vent issue, he took out the new coils that he had installed and put my old ones back in. Seemed to me that he might have asked me first if I wanted to keep the new ones, but he didn't. And I was too frustrated at that point to even think about asking to keep them.
Fortunately, I was "only" charged for a service call - $69. At that point, I was just glad he wasn't charging by the hour...

Jakvis - I appreciate your perspective on this. Now that I have had a couple of days to reflect, I agree that the technician could not have been too experienced. (The company got great feedback on AngiesList, but this guy may have been the exception.) I did mention the possibiity of bad coils as I explained the problem to him, so maybe I am partly to blame. But I would think he would have checked the flame with/without vent earlier in the service call. He was here close to 90 minutes, talking to a co-worker about the possibility of a bad motor, ignitor, etc. before he decided to check the vent. When he determined that it was a vent issue, he took out the new coils that he had installed and put my old ones back in. Seemed to me that he might have asked me first if I wanted to keep the new ones, but he didn't. And I was too frustrated at that point to even think about asking to keep them.
Fortunately, I was "only" charged for a service call - $69. At that point, I was just glad he wasn't charging by the hour...

Sorry for the double post.

My gas dryer did the same thing, turned out to be the the thermister and therostat, quick cheap repair, no need to replace the dryer

gates1,
Did you fix it yourself??
My GE Harmony dryer said the thermister is not functioning properly along with the blower.
I wonder if it's worth fixing????

I have a hotpoint gas dryer that's not heating. I took it apart. I just don't know how to tell what to replace.

Teacher,

Determining the problem requires electrical testing (with a volt/ohm meter) of various components to pinpoint which is bad. Or you can be a PCM (parts changing monkey) and replace several items with the hope of including the correct one for the fix.