Bedrock1,
Ok, lots of comments above, lots of good advice. Time for us to take a break and for you to troubleshoot in a methodical way, and you’ll have to do the work on that.
Based on the above comments, do the following and answer each of the following questions so that we have solid information to go on:
-Take the covers off the Tundra’s blower box.
-Take the covers off the unused 8” outlets on the top of the furnace.
-Temporarily close your 6 registers to the house. Use dampers, tape over the registers, whatever is effective.
-Use a thermometer to measure your basement temperature.
-Open a window 1/4 inch. Open the door to the basement.
-Make a typical fire. Keep the damper open unless you think you are overheating.
Questions:
1. Does the blower eventually come on? How long did it take for the blower to energize after you started your fire?
2. Within 20 minutes of starting the fire, is the blower staying on? If not, is there hot air rising from the top outlets? Use a thermometer—what is the temperature of the air coming from the outlets?
3. After the blower has been running for 10 continuous minutes, is there a strong and fast airflow coming from the uncovered outlets? Is the air warm? Use a thermometer—what is the air temperature?
4. Keep the fire going strong for 4 hours (without overheating). After 4 hours, has your basement heated up? What is the temperature after 4 hours, in the same location as your initial measurement?
5. What is the outdoor temperature? Is it windy?
6. Did you notice the damper close by itself at any time in the four hours when you had the damper switch on “open”?
7. Are you reporting temperature in Celsius?
Do the procedure above, and report back with detailed results to all of the above questions. The results should help quickly narrow down the cause(s) of your problems, which could be any of the many things suggested. We’ve all offered a lot of possible causes in 3 or 4 threads for you to consider, now it’s up to you to do the work to troubleshoot before our help can be effective. I understand if you don’t want to do the troubleshooting. No problem, then call in the HVAC technician and we’ll move on to a different topic.
And also remember to replace your Tundra covers and open your registers when you’re done with the above experiment.