Keystoker 90, Not burning hot enough

We have a Keystoker 90,000 direct vent, this is our 5th season heating with it, we use it in our addition and it usually keeps the whole house warm. We use the Coal Trol had everything set up the same as previous years but this year the coal is not burning hot enough to maintain the temp, the thermostat is set to 80 degrees both day and night and the stove is barely keeping the room at 72 degrees. We cleaned the stove at the end of last season and again checked it at the beginning of the season, cleaned the grates and cemented. I started with the coal trol as I thought the problem might be there, I increased the max setting on the unit, I had to go all the way to 99 to get the 2" of ash on the end and it is still at a feed rate of 99 because the unit is still calling for heat. I thought for sure I would be pushing hot coals off the end with this max this high. I am beginning to wonder now if I have an issue getting air to the coal, maybe with the grates? My flames are low and it seems to be burning slow. Anything else I should be checking? The vent pipe is not hot, just warm to touch. I did open the combustion motor inlet a bit from the factory setting, which we have never had to do. With the price of fuel oil I would like to get this figured out, right now I have to supplement with my furnace. Thanks.

You oiled combustion motor? Vacuum ed under the grate? Cleaned out the holes in the grates? Checked to make sure feed mechanism is not jambed/free moving?

You shut down and checked the entire exhaust path through the vent? Made sure nothing plugged vent outside?

We vacuumed and cleaned everything out, oiled the motor, we had to replace a piece of the piping this year so everything is cleared to the outside. I will re-check the feed mechanism. Thanks for your reply.

Just trying to methodically rule out problems. Hope you find it.

5 years has probably seen many tons of coal…

Power vent fan blade cleaned and that motor oiled??
Sorry if I messed this being already reported.

Did maybe replacing that piece of pipe let crud drop down near power vent. Partial blocking of the exhaust path makes for a weak fire.

I have a Keystoker 105 BTU stove. I have the same issue. I've been running the stove since about 2005. The stove is currently not putting out enough heat for the house. I have the coaltrol thermostat firing rate MAX set at 99. On the stove, the coal feed nut at the back of the stoker is all the way in. According to Keystoker, hot coals should be falling off of the grate. Instead, 6" of ash is at the end of the grate and the fire is low. I wonder if the thermostat module could be to blame? Is the speed of the stoker motor controlled by the Coaltrol module? Could something else be going on? It seems clear that the coal feed rate needs to increase.

D Rock wrote: ↑

Wed. Nov. 23, 2022 7:36 am

I have a Keystoker 105 BTU stove. I have the same issue. I've been running the stove since about 2005. The stove is currently not putting out enough heat for the house. I have the coaltrol thermostat firing rate MAX set at 99. On the stove, the coal feed nut at the back of the stoker is all the way in. According to Keystoker, hot coals should be falling off of the grate. Instead, 6" of ash is at the end of the grate and the fire is low. I wonder if the thermostat module could be to blame? Is the speed of the stoker motor controlled by the Coaltrol module? Could something else be going on? It seems clear that the coal feed rate needs to increase.

Check the suggestions in the thread you started.