Triac Circuit Issues

[DonFL]

Very cool. Tbone nailed it being one of those two. I would agree it is is likely the cap, rather than the resistor, that is your issue.

As far as resistor testing, you typically need to check them out of circuit so you're measuring just the resistor, and not everything else that is in parallel with it.

You can check the cap with an ohmmeter to see if it is shorted, but if open, you won't know for sure if checking with just an ohmmeter.

[tbone321]

Glad to hear that you got it working.  You should be able to pick up both of those parts at the Shack.  They are not worth all that much anymore but they still seem to have some of the basic stuff.  The resistor may be tricky (low value) but they should have the cap.  Unless the resistor cracked during removal, you should be able to clean it back up and reuse it provided you have enough lead length but I would toss and replace the cap.