Harman 3000 not getting enough air?

Hi another winter coming I fired up on sunday and my Harmon wont burn rite the coal is burning all the way to the end of the grate but not making heat? It took 4 hours to get water to 160 I dont think it is getting enough air i have messed with thev flap in the end of the blower and it doesnt seem to change so i turned up my extra fan and it burned better but set off my co2 detector? The stove worked fine when i tore it down for summer help im lost . Blower is running and not making any noise like bad bearings.

Have you checked under the grates to see if there is a buildup of fines? Any chance the grates aren't sealed properly and the air is not going through the coal bed?

Thanks for reply stove was clean . I tore it down in april for the summer . I think im going to call and have draft in chimney checked might have bird nest or who knows what . Since 1st post co2 alarm went off again so i put fire out.

It is hard in this warm weather to get a good draft going, especially in a tight house. Did you try cracking a window near the appliance?

I know it seems clean but did you look under the grate to see if there is any build up? Did you pass a drill through each and every air hole in the grate? Checked all exhaust pipes for ash build up? Looked inside the squirrel cage of the blower to see if the fins are clogged with lint? If you put a mirror in the clean out of the chimney & look up, can you see sky? If you do not have an anemometer, it's time to think about getting one. It's the only way of knowing what your draft is.

Thanks everyone problem is fixed. I think I will blame it on the earthquake. On the bottom of Harman firebox there is a slider to remove flyash when the stove is running. I put the shopvac in before putting grates back in but never looked under from ash pit. When I dumped ashes this am the plate was in the ashes. This was my air leak and pushing down instead of up through grates. So I have to say the earthquake must of made the bolt fall out and plate fall into ash bin over the summer. At least thats my story