Jensen air flow issue

[Dfmihm]

Hey everyone! New guy here, not so much new to boilers but it’s been a while.

Long story short, re-plumbed in an old Jensen boiler that was in the house for decades. Everything working well even with the floor heat, but only with wood. Burning coal has not been great. I have noticed I’m not getting much air flow from the fan up through the grates. Now I haven’t torn much apart but just looking through it I wonder if something is just plugged up. When I first started, I did vacuum it out and change the door gasket material. All in all it worked well, but just noticing also when the fan kicks on, I really don’t see much change in the fire box like I remember seeing this furnace do when I was younger. Any ideas where maybe to start?

Also, yes the blower does run pretty quiet. Attaching some pics for reference.

Thanks everyone

 

[LogCabinFever]

Welcome! I’m a Jensen user as well, although forced air. They use a lot of wood/coal, but they are super simple.

If the blower is fine and everything is sealed, all I can think of is maybe your draft isn’t good. Maybe coal requires a better draft than wood? How’s your chimney? When was the last time it was cleaned? I find that to be crucial.