Just had a tech out today. Gas pressure was up way higher than it should have been so he reduced it (he said it was a 7 something and it should've been 3.4?). CO detectors not going off but they are the ones that only detect above 30ppm.
Oddities: Noticed that the burners will ignite fine and run until goal temp is reached. Then the flames go off but the fan etc still runs. It does this for another 5 or so minutes before the flames turn back on and the furnace continues to run for an additional few minutes. Then everything shuts off. By this time it has reached 1 degree above goal temp.
After tech left I noticed a humming sound coming from it when the furnace is not running. Called back and they said it sounds like the transformer but it was otherwise quiet before tech was out.
Is it okay to leave it as is and monitor or should I be looking to replace ASAP?I really wanted to get through 1 more winter before replacing it as I have other structural home repairs that need addressed as well.
If it's okay to monitor - what temp should I set it to to try and slow down further cracking? (If that's even possible)