Accentra draft issue?

[DGerks]

New to the site but have been nosing around here for a couple of years on and off to cleaning tips etc. I have a Harman Accentra that quit working out of the blue. I would have called the company that we purchased the stove through for assitance but they are no longer in business.

One morning the stove was off when we got up. I had only burned 15-20 bags of pellets in it before this happened. I cleaned the stove thinking maybe it was due to a change in pellets but that was not the case. I going through the wiring diagram of the stove it was determined that we lost power post pressure switch. I purchased a new one and guess what, nothing changed. In reading through some posts on here and the troubleshooting section it sounds like pressure switches do not normally fail.

If I apply some suction via a piece of vac hose to the switch all it well and the stove works fine. I cleaned the filter in the hopper and made sure the hose from the filter to hopper did not have anything clogging it. I also looked at the hopper seal and it is intact and seems to seal well. The door seal also appears to be just fine. I did check the low draft voltage set screw and it is turned up to the highest setting. The stove is vented through the roof in our sunroom and is using room air for combustion.

Yesterday afternoon for the heck of it I got up on the roof and pulled the chimney cap just to see if a bird had possibly tried making a nest in there and the pipe is clear of any obstructions. Anyone got any ideas?

Thanks!

 

[DGerks]

Forgot to mention that if I install a jumper to remove the pressure switch from the circuit the stove works fine.

 

[SmokeyTheBear]

The entire combustion air path must be clean and all gaskets good.

Have you done a full cleaning lately and tested your gaskets?

 

[kinsmanstoves]

The air switch can go bad but I will say that there is a blockage in the exhaust. start at the stove and go all the way up. Pull the pipe apart if you have too.

Eric

 

[DGerks]

The stove was cleaned at the begining of the season and we used it a short time before it quit on us. I did a cleaning and tried it again thinking it might be due to a pellet change. The vent pipe was cleaned all the way up to about a foot from the chimney as that is as far as my brush reaches. When I took the chimney off to check for blockage such as a birds nest I could see all the way to the bottom( 12 feet in lenght give or take) and it is very clean inside. I was thinking a blockage also and could not find anything.

None of the gaskets appear to have any damage and seem to be in good shape. How would you go about testing them? The hopper I could see possibly putting a little bit of water on to ensure a good seal for test purposes but what about the rope seal around the door?

 

[kinsmanstoves]

did you check the cap?

 

[kinsmanstoves]

Does this unit have the hopper lid switch?

 

[DGerks]

Cap on the drop leg? If so the thing is crazy tight but I will see if I can turn it a little more.

No switch on the hopper lid.

 

[DGerks]

Forgot to mention no blikling lights on the control board either.

 

[kinsmanstoves]

Forgot to mention no blikling lights on the control board either.

You will not get a blinking light for an air flow issue.

 

[kinsmanstoves]

Cap on the drop leg? If so the thing is crazy tight but I will see if I can turn it a little more.

No switch on the hopper lid.

Make sure the yellow plastic defuser is not blocked with fines and the lid is shut tight.

"Drop leg"? That is the tee cap I think you are talking about. If you have not removed that, I will bet you $5 that is where it is clogged.

Eric

 

[DGerks]

Cleaned the back of the stove also and have thrown a jumper in to bypass the pressure switch and everything works fine. The tee is what I callled the drop leg. When I clean the stove I always pull the cap and clean up as far as I can in the vent pipe. In looking in the front of the stove with a flashlight at the bottom of the tee there is nothing clogged. I think I am going to give the stove anotehr once over to see if I am missing something. So far it seems like I was on the right path for the most part.

 

[kinsmanstoves]

Bypassing the pressure switch will be the same as it running under normal conditions. It just might be a bad switch but I would look else where like to the hopper lid not sealing.

Eric

 

[DGerks]

FIgured as much but thought I should note that. This is the second switch I have tried and with a section of hose connected to it and a slight amount of suction by me on the hose the switch will close and operate as it should. I have checked both switches, original and once recently purchased, with a meter and both seem to be working. As far as the hopper lid goes with the stove only being a few years old could the seal have gone bad already? I just took a look at it again and it appears to be intact with no damage. I will try a little water dabbed on it to see if I can get a better seal on it and will report back.

 

[kinsmanstoves]

FIgured as much but thought I should note that. This is the second switch I have tried and with a section of hose connected to it and a slight amount of suction by me on the hose the switch will close and operate as it should. I have checked both switches, original and once recently purchased, with a meter and both seem to be working. As far as the hopper lid goes with the stove only being a few years old could the seal have gone bad already? I just took a look at it again and it appears to be intact with no damage. I will try a little water dabbed on it to see if I can get a better seal on it and will report back.

Inside the hopper there will be a little plastic defuser, usually yellow or orange. make sure that is clear.

 

[SmokeyTheBear]

The stove was cleaned at the begining of the season and we used it a short time before it quit on us. I did a cleaning and tried it again thinking it might be due to a pellet change. The vent pipe was cleaned all the way up to about a foot from the chimney as that is as far as my brush reaches. When I took the chimney off to check for blockage such as a birds nest I could see all the way to the bottom( 12 feet in lenght give or take) and it is very clean inside. I was thinking a blockage also and could not find anything.

None of the gaskets appear to have any damage and seem to be in good shape. How would you go about testing them? The hopper I could see possibly putting a little bit of water on to ensure a good seal for test purposes but what about the rope seal around the door?

Use a piece of paper about the size of a dollar bill, place it between the door and gasket at two separated points on each side of the door close the door on the paper.

Pull on the paper it should come out but present resistance at every single test point, if any point doesn't present resistance, you need to find out if the door can be adjusted and then do so followed by a retest.

If you can't get the test to pass at every point, you replace the gasket.

 

[DGerks]

Ok so after putting water on the hopper lid seal and holding it down by pushing down on it we started running again. I put some painters tape around the hopper lid as a temp test to see if we would stay operational. That was short lived as the auger did not seem to feeding enough. The stove seems to have draft and then will lose it for some reason. Tried the water on the hopper gasket ane pushing down on it again with no luck. Tried the painters tape and still not luck. Everything seemed to be running fine there for just long enought to get the temp probe hot enough to get the distribution blower going again. I am back to square one here and can make the pressure switch operate by putting a little vac to it it with a piece of hose. I can also "hotwire" it as I did before and it will run fine.

 

[SmokeyTheBear]

There is more than that hooper lid gasket for gaskets on that stove.

 

[kinsmanstoves]

There is more than that hooper lid gasket for gaskets on that stove.

There are a couple screws that hold that top down. Remove them and check that seal. You know where the problem is and you have to fix it. Do not hotwire the neg pressure switch.

Eric

 

[DGerks]

I think I am going to replace the hopper seal and the screw seals. I wetted down the hopper seal again and did the painters tape over the screws and around the hopper and the stove is "working" for the time being. It will run for a while and then it seems to run out pellets and then will flash a code 6 on the control. If you turn the feed knob to test and the stove to off it will start feeding pellets again the the status light stops blinking. It will run a while before this happens again but it is "working" as I said. I am going to shut it down before we turn in for the night and order up a seal from Eric tomorrow. More to follow after I have the hopper seal replaced.

 

[DGerks]

Still need to replace the hopper seals there is something else going on with the stove. The stove did not seem to be getting enough pellets and output was low so I spent some time watching its operation again this morning. There are times when the feed light comes on but the feed motor does not run. There are times when the light is on when there is no voltage output from the control board. Other times it works fine and the feed will run. There are also some times when it will only make a revolution or two and then power output from the board will drop out again. Sounds like a control board issue to me.

 

[SmokeyTheBear]

Well, did you check the other gaskets?

That vacuum switch can change state several times thereby sometimes allowing the feed to take palace and then not.

Then again it could be a bad control board.

Where are you measuring the voltage from the control board?

 

[DGerks]

Door and glass gaskets all appear to be good. If I need to check any other gaskets I am going to have to tear the stove down to do so unless there is another one you suggest. I can consistently get the unit to lose draft if I remove the painters tape from around the hopper. As far as the feed motor voltage goes I was checking it at the leads that supply the motor closest to it.There are two wires one blue and one black. The black wire comes from the control board and is the positve voltage. When the feed light comes on I am getting around 117 volts to the black wire.

 

[kinsmanstoves]

. As far as the feed motor voltage goes I was checking it at the leads that supply the motor closest to it.There are two wires one blue and one black. The black wire comes from the control board and is the positve voltage. When the feed light comes on I am getting around 117 volts to the black wire.

The pressure switch blocks that voltage prior to it hitting the feed motor. Look at the schematic.

 

[DGerks]

I figured when initially looking at the schematic I would see power on the blue wire and I am getting it on the black when the control calls for feed.