Biomass 60 lower door heat shield attachment

[MarkW]

I'm out of town but heard from my GF that the lower door heat shield has partly detached. How are these held on? I'd like to be somewhat prepared for what I find when I get home.

 

[woodsmaster]

there are screws on the sides of the door that hold the skin on. Take the skin off and there are two bolts that hold the shield on. Probably have to cut the bolts to get them out. You will probably need a new shield as the old one may crumble. Ive been running mine without the shield for over a year now. the door itself is also filled with refractory. I have a new one to put on but not to worried about it.

 

[MarkW]

what holds them to the shield? threads inserts or cast in place studs?
I would hope it wouldnt crumble the first year.

 

[Tennman]

Ditto. Been a while... maybe ~3-4 years ago. As I recall the lower door had two layers of ceramic brick. First one broke/fell off long time ago and having the one against door has been working fine. Those door firebrick studs are located at about the ugliest, hottest location where the blast makes the turn to the rear exit. I can't image either getting the nut off or a new nut on to replace the door brick. When that day comes I'll probably remove the door and weld new studs on. I'm assuming their welded to the metal door cover. Maybe JT's had his apart.

BTW... I recommend getting some of that silicone door gasket from NH and keeping it on hand. I blew thru several lower door gaskets this season for some reason. Spring cleaning will include replacing ALL door seals, top and bottom. Hope he didn't change material or suppliers on that stuff. Not sure why it didn't last as long. Maybe due to running higher pressures (100% fan) this season.

BTW #2... my 3/16" nozzle shield worked well to protect my nozzle opening...BUT it potato chipped (warped) during the season. Gonna go thicker next year... but the mild steel, plasma cut nozzle guard held up well. Little to no erosion on the opening. Also this year I tried to leave some ash to protect the nozzle edge.

Best season yet running the BioMass... good thing... worst temps ever in this home. I'll bet we saved $5-6K in propane since November! Next season Storage!

 

[MarkW]

My 5/16 304 nozzle shield didnt last a week before it warped and allowed the air to flow under causing bridging.

If its nuts on studs mounted to the door then its a recipe for failure. Not going to last long in that location.

 

[woodsmaster]

I haven't had mine apart, but from what Zenon told me after the cover is off the bolts are easily replaceable.

 

[woodsmaster]

If the refractory is bad it will be covered under warranty.

 

[evamaxx]

If the refractory is bad it will be covered under warranty.

I have bio 60 and gasket went bad but it was because piece of refactory damage it and I tried to close door hard it was gassing big time had to get door close fast I pushed damper open to take heat away from bottom to look at it any way after replacing gasket it still leaked bad I though door was sprung but it was not it called nh and zennon went through the trouble shooting list but no fix so I run 3 weeks in cold with leaking bad and not much heat output I called him again and this time we figured it out when I cleaned out boiler I didn't clean the side passages in lower chamber count see them and I forgot what it looked like in the beginning so all clean no leak working great again in md we had a cccold winter than in past long time broke some records hope some of my mesakes helps someone else out mark oh I have my 60 in an outbuilding so smoke was not an problem if some one asks

 

[MarkW]

I took a peek last night when I got home. The outer, smaller diameter section is free. There is a metal plate with 2 studs that is still mounted to the larger section, though loosely. The nuts are gone but the threads appeared ok, from what I could tell without getting too involved. I didn't want to do too much as I needed it running with the cold snap we have for yesterday and today. Supposed to warm up some tomorrow and Saturday so I can shut it down and see what's going on. The refractory seemed soft but I'll have to get it apart to be certain. I'll approach the warranty issue based on what I find, then.

 

[Tennman]

Maxx & Mark... I presume you've also removed the lower aft access door to clean ash from the bottom chamber. I was slow in checking mine this season because with well seasoned wood and my new fan/vent settings the ash in the lower chamber was quite a bit less than what I experienced in previous years. About a month ago after ~3 months of burning checked the ash in the lower aft chamber and it was very full. That also blocks/chokes flow from the lower chamber significantly hurting boiler output.

Probably a name for that chamber below the tubes, but I don't know what it is.

Mark, my memory is weak on this but as I recall there was like a counter bore in the lower door ceramic that broke/fell off my door. I forgot to look how the remaining ceramic block is being held to the door. Except that it's those two studs. Anyway, I've proven that two ceramic blocks on the lower door is unnecessary.

 

[MarkW]

I've cleaned my lower turb chamber 3x so far. The first time there was a fair bit on each side from a longer time running but not so much on the successive occasions. My output has generally been quite good. I did pull the upper cover off once but there wasn't anything to speak of on top of the tubes.

 

[ElkRiverFJ]

We're talking about the ceramic mounted to the inside of the door facing the lower chamber, correct? After just a few months of operation I opened the door one day and found one of the nuts with a piece of the threaded bolt fallen off with the washer and laying on the floor. I'm waiting for the other one to break as well. So far the refractory has stayed in place pretty well (this is on a BioMass 25).

 

[MarkW]

Yes, Elk. That's exactly what we are talking about. I have not checked for the remains of the hardware, yet. Both nuts have gone on mine, however and the plate drops off the studs when the door is opened.

 

[Tennman]

From my experience the double ceramic plate on the lower door was overkill and obviously the attachment was poorly designed. About my only gripe on the design.

This season with it being so cold I've left the fan at 100% and it's been the best season yet since demand reduced idling. Totally dispelling my attempts/advice I posted in the early years of choking the vents and using 60% fan to get long burns. When you Google "school of hard knocks" my picture pops up. But next year it ALL comes together with 1000 gals and the Laddomat. That will make shoulder season heating practical.

 

[MarkW]

I run it pretty well wide open with fan at 100% but my current 450g storage hasn't been enough to carry us over with the current winter fun we've had this season. Hopefully, 1500g next year and 0 idle times (crossing fingers for new house).

 

[evamaxx]

I run it pretty well wide open with fan at 100% but my current 450g storage hasn't been enough to carry us over with the current winter fun we've had this season. Hopefully, 1500g next year and 0 idle times (crossing fingers for new house).

after the first failure I replaced the bolts with hi- temp stainless steel and put a big glob of refactory cement on parts that stuck out been 6 mo no problem this spring ill chip it off and take a look but it looks ok now

 

[MarkW]

I was thinking about doing something similar.