King Stove Pulsating Blower

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gibbons8085

New Member
Dec 19, 2021
9
Valve9463
So here is my issue, the stupid combustion blower pulsating is making it exceptionally hard to keep a nice consistent hot fire. It goes from lazy orange dark tips to a nice hot white fire with fast tips. Has anyone found anything that helps?
 
Have you unplugged it for a few min and plugged it back in? Are you using a surge protector? Do you have an outside air kit hooked up and when was it cleaned last and how deep of a clean? Leaf blower trick is always recommended
 
BLOWER MOTORS
Clean the air holes on the motors of both the exhaust and distribution blowers annually. Remove the exhaust blower from the exhaust duct and clean out the internal fan blades as part of your fall start-up. If you have indoor pets your power motors should be inspected monthly to make sure they are free of animal hair build up. Animal hair build up in blowers can result in poor performance or unforeseen safety hazards.

Your manual has a decent troubleshooting guide as well, unless you’ve tried these already

 
ya the combustion blower pulsates from that factory by design. IT SUCKS
Ok, just thought I’d try and help however I could, most problems are caused from neglect, starting with lack of proper maintenance and or cleaning.
 
Ok, just thought I’d try and help however I could, most problems are caused from neglect, starting with lack of proper maintenance and or cleaning.

A good cleaning is always my first go to and a good idea.

In this case, however, the draft motor pulses by design. I have a Ussc 6500 and it does the same thing. I have read where some people say it is supposed to do it until the stove comes up to temp, but mine never stops. Others say it always does it.

For the OP, I look at the flame on mine but I also watch the pellets in the burn pot to see how well they are combusting. It is slowing overfilling etc. also, if you have a glass door, how long until it gets dirty?
 
Out of my 2 stoves, the glass on my ussc gets dirty faster but it burns the pellets well
So it seems if I run it at 2lb/hr which to me seems more like 2.5 I get a nice hot fire that burns the pellets well. If i run it it anything lower I lose my flame intermittently on the ramp up of the combustion blower. If I lower the blower settings then my pot starts filling up and will spill over in less than 24 hrs. Stove is literally less than a week old
 
So it seems if I run it at 2lb/hr which to me seems more like 2.5 I get a nice hot fire that burns the pellets well. If i run it it anything lower I lose my flame intermittently on the ramp up of the combustion blower. If I lower the blower settings then my pot starts filling up and will spill over in less than 24 hrs. Stove is literally less than a week old

Mine also pulls the flame down quite a bit when the motor pulses.

You mentioned setting it at 2pph. Can you elaborate on how you set this?

Also, how many heat levels does yours have? Mine has 3. When adjusting the PPH feed rate on mine, the process is to set the low (PR1 feed rate) and then set the high (PR3 for me) feed rate. Then the levels in between are figured by the board. I have mine set for 1.6pph on PR1 and 5pph on PR3.

An overflowing fire pot does point to an air flow issue. Have you made any adjustments to the draft low and high settings?

I also have mine set to run off a room thermostat. This means I try to set my PR1 pph/draft setting very low so it is almost just a pilot lite. Then when the thermostat calls for heat the stove kicks up to PR2 or PR3 depending on where I have it set at.

If I was not using a thermostat I would probably set my PR1 heat output slightly higher so it would be more usable.

Have you looked at the USSC Troubleshooting sticky thread at the top. In that thread there are a lot of Technical manuals available that help explain all the different settings that you can adjust and tell how to do it.
 
Mine also pulls the flame down quite a bit when the motor pulses.

You mentioned setting it at 2pph. Can you elaborate on how you set this?

Also, how many heat levels does yours have? Mine has 3. When adjusting the PPH feed rate on mine, the process is to set the low (PR1 feed rate) and then set the high (PR3 for me) feed rate. Then the levels in between are figured by the board. I have mine set for 1.6pph on PR1 and 5pph on PR3.

An overflowing fire pot does point to an air flow issue. Have you made any adjustments to the draft low and high settings?

I also have mine set to run off a room thermostat. This means I try to set my PR1 pph/draft setting very low so it is almost just a pilot lite. Then when the thermostat calls for heat the stove kicks up to PR2 or PR3 depending on where I have it set at.

If I was not using a thermostat I would probably set my PR1 heat output slightly higher so it would be more usable.

Have you looked at the USSC Troubleshooting sticky thread at the top. In that thread there are a lot of Technical manuals available that help explain all the different settings that you can adjust and tell how to do it.
I have five heat levels. You set high and low and the middle three are figured linearly. US Stove states that I need to have a 3’ vertical rise to have this stove vent properly
 
I have five heat levels. You set high and low and the middle three are figured linearly. US Stove states that I need to have a 3’ vertical rise to have this stove vent properly

Okay. That is the same as mine. Have you made any adjustments to the draft fan settings? On mine they follow the same principle....set the low and high and the inbetween are figured by the board.
 
I have five heat levels. You set high and low and the middle three are figured linearly. US Stove states that I need to have a 3’ vertical rise to have this stove vent properly
Re-read. looks like you have messed with the draft speed.

I will say that my flame is sucked down considerably when the draft motor pulses on and on my pilot light setting (PR1) the flame can be very low when the draft pulls.

On PR1 my flame can also vary drastically as the agitator turns. Sometimes it can simply look like a bed of red coals temporarily until the agitator turns some more.
 
The more I messed with the settings on mine the worse it got. I did a reset to factory settings and it works fine. It really heats well. I leave draft and room fans set on "A" (automatic)Yes the fan pulses and takes some getting use to. It does burn a little rich on setting 1 but not on on 2. I've never had the need to go above 2. I tried the wall thermostat and it didn't work well for me.
 
Re-read. looks like you have messed with the draft speed.

I will say that my flame is sucked down considerably when the draft motor pulses on and on my pilot light setting (PR1) the flame can be very low when the draft pulls.

On PR1 my flame can also vary drastically as the agitator turns. Sometimes it can simply look like a bed of red coals temporarily until the agitator turns some more.
So your saying you set your low as basically a pilot until the thermo calls for heat then it ramps and work better?
 
The more I messed with the settings on mine the worse it got. I did a reset to factory settings and it works fine. It really heats well. I leave draft and room fans set on "A" (automatic)Yes the fan pulses and takes some getting use to. It does burn a little rich on setting 1 but not on on 2. I've never had the need to go above 2. I tried the wall thermostat and it didn't work well for me.

Did you switch them to manual and then adjust, or did you leave them on auto and then go in to the program settings and adjust the parameters? Just curious
 
So your saying you set your low as basically a pilot until the thermo calls for heat then it ramps and work better?

I would say it works better for me and my situation. Hooking up a thermostat doesn't fix a burning issue (feed rate or airflow/draft issue). It makes the stove able to regulate and maintain room temperature better.

You are correct about the way it behaves when hooked up to a thermostat. I put the heat setting on PR2 or PR3. When the thermostat is not calling for heat the stove burns at the lowest PR1 setting (which I have set to be as low as it will maintain a flame). When the thermostat calls for heat the stove ramps up to whatever heat setting I have it on (PR2 or PR3). Once the thermostat is satisfied the stove ramps back down to PR1 and waits. This works well for me because during the day if it is 35-40* at PR1 is enough. At night or when the temp drops into the 20s or below I need PR2 in order to maintain temp, but I don't need PR2 running solid.......only occasionally.

My USSC does not have an ignitor. I light it with a handful of lighting pellets.

On my other PP130 it has an ignitor and if it were hooked up to a thermostat it has the ability to completely shut down and then re-ignite when the thermostat calls for heat (if I set it to do it).

If yours has an ignitor, you will want to research and see if it will re-ignite or not. Either way, the basic principle is the same.
 


Here is a video of the flame on mine. Set on PR1. You can see it suck way down when the draft motor pulses.

Also, this is a large flame for PR1 for mine. 30 seconds later after the agitator stirred it some it looked like there was almost no flame at all. Then it came back after a couple of pellets were dropped and the agitator spun again.