Harman Super Magnum Stoker Issue

I bought the Harman Magnum coal stoker 4 years ago and had it professionally installed in my 3000 plus sq. ft old stone farmhouse. I havent had to use the oil baseboard heat in 4 years. I noticed when the temp outside is below 20 the stove doesnt seem to throw the heat that it used to. My feed rate is steadfast at 1.5 wether I have the stove temp set at 2 or all the way to 7. I currently have the stove temp set 7 and it doesnt seem to throw the heat. I average between 5-7 tons of rice coal per year. anyone else with similar issues and are there any recommendations? Thanks in advance

Whats your cleaning regimen like ?
Hows your draft ?
Different Coal ?

I am not too familiar with the controls on the super mag other than it uses both a temp sensor and an exhaust sensor to come up with feed rate and combustion air for the appropriate burn. What are your flue temps and do you have a manometer to measure draft? if so what is the reading? What was the feed rate in the past when it was throwing a lot of heat? Do you have a co monitor?

Some ideas to look at until a super mag owner checks in...
Is the restrictor plate on the combustion fan open the same amount as it was before?

Are the holes in the grates cleaned out?

Flue pipe cleaned out?

Have you cleaned out the ash under the grates lately?

How high are the flames in the firebox?

Is the exhaust sensor probe connected properly to the controller?

Is the coal unusually wet or does it contain a lot of fines?

Like I posted many times here mine has been working flawless since October. It is brand new I will confess. And I do have a manometer. My feed rate is 2. The fan is set to just above low as the stove will increase it when needed. I use the room temp probe. You can extend it as it will only change the setting numbers but not the function. Example is the control panels setting for room temp (not stove temp) might read 75 deg but the room up stairs and many feet away might read 70 deg. But the probe will keep it within a couple of degrees steady for sure. When the heat is at high output my manometer reads .07 to .08 which is what Harman wants.
I assume you work the rod in and out in the hopper for cleaning the ex-changer. Also check to make sure the clean out for under the grate is closed. # 5 in the bottom of the photo.
Why don't you try using the temp probe instead.

I may have found the problem. Just discovered the left grate burned through. This is the second time in 4 years. Not happy!

Bruno wrote:I may have found the problem. Just discovered the left grate burned through. This is the second time in 4 years. Not happy!

Really?! My stove is two generations older than that one (and about 20+ years older) and has the original grates. What do they look like when they burn through? I wouldn't be happy, either. It's not like Harman didn't know how hot they would get, or they didn't ever manufacture a stove before. That's amazing.

Bruno wrote:I may have found the problem. Just discovered the left grate burned through. This is the second time in 4 years. Not happy!

That is incredible. Please post pics of the grates.

Yeah, since those are probably the same as in the boiler you and I have Coalkirk.

Kevin

I just replaced mine after 10 years and they were really still very usable.

Might I ask why? And what did you observe about them, or what was worn out?

Kevin

The burned coal was fused together and an inconsistent glow of flame. I looked closer after ashes dropped and noticed the hole in the left grate. I turned the stove off and waiting for the ashes to cool to inspect. Im doing renovations in the 1st floor of hose and now I have the kerosene stove to keep warm. I pray that the Harman dealer has them in stock when I go tomorrow. I cleaned the stoe about 1 month ago and the grates were in perfect condition- no warping and cleaned.

Let us know how much these grates cost, imagine the two of them should be replaced together?

Bruno wrote:The burned coal was fused together and an inconsistent glow of flame. I looked closer after ashes dropped and noticed the hole in the left grate. I turned the stove off and waiting for the ashes to cool to inspect. Im doing renovations in the 1st floor of hose and now I have the kerosene stove to keep warm. I pray that the Harman dealer has them in stock when I go tomorrow. I cleaned the stoe about 1 month ago and the grates were in perfect condition- no warping and cleaned.

Most Harman dealers in my experience do not stock these. They are about $85.00 and usually take a week to get them.

KLook wrote:Might I ask why? And what did you observe about them, or what was worn out?

Kevin

No warping but they were showing wear. I am keeping them as spares. I decided to buy them when I saw Harman had discontinued the vf3000.

After the stove cooled I was able to inspect and found the grate did not burn through it was completely missing. Apprarently coal pushed it off and into the ashes and I did not know it. I had cleaned the stove and inserted the grates about a month ago without issue. The stove was working flawless until the extreme cold weather set in. I figured the way the coal fused together was related to the damper settings. I did not find the grate in the ashes and Harman is backordered. I went to the dealer and they had them , unfortunately they charged me $92.00 for the two. He suggested sanding the grates smooth. I did and the stove is working perfect again. Thanks for the input.