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Slant/Fin Liberty L-20 observation door repair

DanRegienusDanRegienus Posts: 23Member
I recently had my boiler inspected and in the process the service tech broke off the observation door on the front burner plate. I'm not sure if he did something wrong (he seemed to be in a rush to get my inspection done) or if the door was just in bad shape and it was inevitable, but regardless the door has been broken off the front burner mounting plate. He did not go into detail as far as what happened but I believe he had said something to the effect "the bolts broke off". I was not around to witness the damage myself, but when I got home I found he had placed a length of metal strapping from the left side to the right side of the boiler screwed in with sheet metal screws across the face of the observation door caked in furnace cement. With all the furnace cement caked on the door it is impossible to see anything (I can't see the condition of the door or the location of broken bolts). I have to remove the burner and front burner mounting plate this week in order to replace the firebox insulation (rear target wall, front refractory, floor blanket) so I was wondering if anyone could shed some light on the repair procedure I'm in for. I have gone ahead and ordered a new door kit which consists of 3 new bolts, the door, and what looks to be a gasket of some sorts. I would like to know what to expect as far as repairing this problem goes because I obviously can't have the boiler inoperable for very long since it's winter time here in MA. I'm guessing it will involve me trying to drill out some broken bolts but I'm not 100% sure. If anyone could help point me in the right direction i would certainly appreciate it. I was also looking for any info/tips/tricks on the burner removal procedure (how to remove burner, fuel lines, and any possible electrical connections). Once again I would greatly appreciate any information, suggestions, or step by step directions anyone might have. Thanks, Dan


  • DanRegienusDanRegienus Posts: 23Member
  • EBEBRATT-EdEBEBRATT-Ed Posts: 5,621Member
    If it's just the round observation door leave it until spring. You can get an observation door from a supply house that sells slant fin. You should be able to drill out the old bolts and re tap the holes. Sometimes you can drill and tap 1 size larger if need be.

    The front of the boiler looks like it has been overheating. Should have the draft checked and make sure the boiler is not overfired.

    Did they leave you a combustion test results
  • DanRegienusDanRegienus Posts: 23Member
    EBEBRATT-ed I'm just curious about the comment you left, what do you see that might indicate the boiler has been overheated? As to your other suggestions, i have already ordered a new door assembly with bolts and a gasket that should be here tomorrow. I figured that since I had to open up the firebox this week to replace the insulation i would also tackle the broken door, I just wanted to get an idea as to what i was getting myself into. If it's just some broken bolts that need to be drilled out i can take care of that without too much trouble. I don't have the combustion results on hand but what ever the results were led the tech to open the observation door and check the condition of the insulation and refractory panels. They were all completely broken down and laying on the bottom of the boiler in chunks. He vacuumed them all out and left me with a 5 gallon bucket full of disintegrated refractory panels and chunks of insulation. Thanks again for the insight.
  • EBEBRATT-EdEBEBRATT-Ed Posts: 5,621Member
    Maybe it's just the picture which doesn't show that much I was looking at the area above the boiler/burner plate to the left and right of the on off switch looks a different color.
  • STEVEusaPASTEVEusaPA Posts: 2,818Member
    edited March 4
    Why do you have to fix it and not the tech who broke it?
    So a 'tech' came out for an inspection and you have to fix the door and replace the chamber?
    Who’s doing the combustion analysis when it’s finished?
  • DanRegienusDanRegienus Posts: 23Member
    I had a local company come over to do an inspection on the boiler because it seemed to be burning more fuel than normal and during the inspection the service tech tried removing the observation door to inspect the firebox chamber and broke it. Once the observation door was off he looked inside and saw the insulation was crumbling and deteriorated and had fallen to the bottom floor so he vacuumed it out and told me it needed to be replaced. As far as the door, he said he did not have one and wouldn't be able to get one for a few days so he put that strap and furnace cement on for the time being. He then wrote me up an estimate to replace the insulation for $470.77 (includes parts) and gave me a ballpark estimate of $250 (includes parts) to replace the observation door. I don't have a ton of extra cash lying around so I went online and ordered a new insulation kit (Lynn 1087) and a new door kit from Slant/Fin for $130 for both parts and will install them myself. Then I have a friend who will redo the combustion test.
  • HVACNUTHVACNUT Posts: 2,031Member
    The inspection door bolt was seized. He tried to loosen it to check the chamber and the bolt snapped. Cant really fault the tech on that.
    Spray WD or penetrating oil on the door bolts now so hopefully they wont be an issue.

    Now, the price given was not for parts. It was for a repair.
    What happens if say, you remove the burner from the door (needs a new burner flange gasket now) and the air tube is cooked and warped?
    Or you trip over something and kink the oil line? Things just went seriously sideways.
    My point is, everything goes according to plan until it doesn't. Then what?
    Do you have a soot vac? Say goodbye to your wet/dry vac if you plan on using it. Its little things like that that will absolutely ruin your weekend. And you'll be mumbling to yourself the whole time, "Shoulda had the guy do it. Shoulda had the guy do it."
  • DanRegienusDanRegienus Posts: 23Member
    I understand your point but I would not consider doing the job unless I had all bases covered. I do have a proper soot vac and when I ordered my replacement observation door parts i also ordered a New Carlin burner gasket along with new studs/nuts should something go sideways. I always run over the worst case scenario in my head for each step of the repair and plan/equip myself accordingly. I make sure I have the replacement parts on hand in case I need them. I even have a new filter, new bleeder valve and 30 feet of oil line with various fittings should I need it. Also the prices i was given did include parts and labour.
  • DanRegienusDanRegienus Posts: 23Member
    Just to be clear, I don't blame the service tech for what happened, I'm sure it was inevitable that the bolt would break. It's just one of those things that happens.
  • STEVEusaPASTEVEusaPA Posts: 2,818Member
    edited March 5
    I've broken/fixed enough bolts, but I never broken a bolt unless on purpose.
    Meaning, if that bolt wouldn't easily come out, I would've sprayed, did something else, try the bolt. Repeating a few times. If that or my other tricks didn't work I would explain to the homeowner that I have to get this bolt out and it's going to break, necessitating a drill/tap repair.
    If this guy broke the bolt by super wrenching on it and cracked the door, it's his fault for not being more careful.
    That's just my opinion.
  • DanRegienusDanRegienus Posts: 23Member
    Just to clear things up, the boiler listed above and the boiler listed on another thread with a cracked door are not the same boiler. They are the same make and model but one is in my house and the other is in my tenants house. After posting this thread about the boiler with the broken observation door i went next door to look at my tenants boiler and discovered the crack in the burner mounting plate door. So the service tech that broke the bolt off the observation door on my boiler is not related to the cracked door on my tenants boiler.
  • STEVEusaPASTEVEusaPA Posts: 2,818Member
  • DanRegienusDanRegienus Posts: 23Member
    I found the remains of the bolt the service tech broke off and there was nothing left to it. It was a 1/4x20 bolt that rusted down to the thickness of pencil lead, maybe a little thicker. So I doubt he really had to reef on it very hard before it broke. The head of the bolt looked fine, there was no telling the shaft of the bolt had deteriorated that much, he probably barely touched the thing and it broke.
  • STEVEusaPASTEVEusaPA Posts: 2,818Member
    Should be easy enough to drill out/tap.
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