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Help with Lochinvar Boiler

ThunderThunder Member Posts: 8
I am one frustrated Lochinvar Owner. I had a new boiler installed last December. I now do not believe that the installer actually was 100% up to speed on how to do the install. First problem was they did some of the piping wrong and I had water going into my floor at 160 and rising. Got that squared away within a couple days thank goodness.

However, I did call in a more experienced contractor that I wish I had just used from the start. He explained that he still not that some of it wasn't piped the way they would have, but it seems to be working. Lochinvar also sent a tech over and clarified that although not exactly piped the way they would recommend, it's working.

Well, is it? I get a weird "hhumpf" sound upon start up. This happened almost immediately and was getting louder. The new contractor came in and checked combustion and got everything zeroed in. Still did not take noise away. Lochinvar says bad gas valve. Replace. Did that. Things sounded good for a couple months. And then the noise is back. This time Lochinvar says replace gas valve again, although strange that two would go bad and also change control board. Did both. Things sounded good....for a couple months.

Then again today. The "hhhumpf" noise is back upon start up. I am so frustrated. I have already poured thousands above and beyond into this stupid boiler.

Does anyone else have any ideas? Other things that would cause this gas valve to work fine upon installation and then begin making this noise? What else should they check? Literally the entire boiler has been checked and double checked. Combustion rates are right on. It does a good job heating the house. It heats two floors, and also a plenum in the furnace to heat the upstairs.

Could it be that something in the plumbing is wrong and maybe not actually "working" ? And to top it off, it doesn't happen EVERY time it starts up.


  • hot_rodhot_rod Member Posts: 14,384
    Gas or LP?
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    The magic is in hydronics, and hydronics is in me
  • ThunderThunder Member Posts: 8
  • BillyOBillyO Member Posts: 245
    had the same problem with a HTP boiler 3 years ago. I drilled a couple of holes in the combustion air piping above the boiler and it solved the problem, go figure
  • GWGW Member Posts: 3,903
    Any rhyme or reason on outdoor temps? I’ve seen LP regulator issues. The guy checked it when it thumps? No other gas appliances running when this happens? 
    Gary Wilson
    Wilson Services, Inc
    Northampton, MA
    [email protected]
  • ThunderThunder Member Posts: 8
    Outdoor air temp doesn't seem to be an issue in my opinion. It's been a pretty mild and steady winter. I don't believe the outside regulator has been checked. But the original installer made a comment about needing to adjust the regulator based on outdoor temps and the more experienced contractor said that shouldn't be so because you would need someone to be adjusting it all year long. (am I understanding your question?)

    As far as other appliances I did sort of think it happens more when the side arm water heater calls for heat but today now I have heard it with the basement floor heat and the furnace plenum kicking on (not at the same time) 
  • EBEBRATT-EdEBEBRATT-Ed Member Posts: 7,994
    The piping has nothing to do with the noise your getting. What you have is an ignition/combustion problem.

    I would suspect a sticking LP regulator. Sometimes LP tanks can have moisture in them. The LP leaving the tank acts just like a refrigerant (in fact it is used as a refrigerant) and if there is a little moisture in the LP or in the regulator it can freeze and cause gas pressure issues.

    Talk with you LP supplier. They will probably check the regulators and they treat the inside of the tanks with basically "LP antifreeze"
  • ThunderThunder Member Posts: 8
    I appreciate the responses so far. Since I seem to have found a forum where people KNOW some things. Another issue this boiler has had from soon after installation is a popping noise as it's increasing in run percentage (I don't know the words for that). Basically it will fire up and then as it's getting up to temp, you can hear a knocking or a popping. They have tested all they know to test and can't confirm what is causing it. They don't feel it's doing any harm. They were hopeful upon getting it all dialed in that it would subside, but instead it used to pop around 60% and now it pops all the way up to 100% flame.

    They sort of thought this may be sediment/hard water as that can sometimes cause this. But this was a brand new boiler and was supposedly filled using the correct PH etc. They have not cleaned out the heat exchanger (is that the right term?)

    I am just concerned that by not figuring it out, it's going to lead to a shorter life on this brand new boiler.
  • HomerJSmithHomerJSmith Member Posts: 1,073
    Well, Lochinvar is a good boiler. LP,huh. Did anyone check the regulator at the house or tank, depending which regulator that you have for about 11" of W/C? As part of commissioning, I always check input pressures and for LP the regulator pressure, too.

    You're LP provider will check the outside regulator pressure for you at no cost.

    Regardless of what the manufacture says about one pump doing it all, I most always pipe the sys in a primary-secondary configuration.

    It is highly unlikely that several gas valves would exhibit the same issues and be defective.

    Pics of your piping would help.
  • kalex1114kalex1114 Member Posts: 104
    can you record the sounds?
  • ThunderThunder Member Posts: 8
    I tried to upload some photos. I have two recordings of the main gas valve noise but I don't know how to load it.

    Update from today was the LP company and my tech both agreed it was a good chance it was the regulator. The LP company came out and replaced the one on the tank and the one on the house. Adding a 2 pound regulator on the house. He also added a couple of adjustment things in the house, you can see one next to the furnace in the picture and one is on top next to the boiler. He also added a test valve because it didn't have one. He said he had the pressure outside set to 13 and when the boiler is running it tests at 11 to 11.5 He also said this spring he needs to come back and trench a bigger line from the tank to the house. We were hopeful that would take care of the noise, BUT no such luck. Noise as present now as ever.

    Something is NOT right. How can we go through 3 gas valves? And how can they work for a short time and then start this noise again.

    I would also like to know why it sounds like popping when it runs at 100% because they say that happens from scale. Why would a new boiler have scale?

    I am beyond frustrated because other than starting completely over, what more they can possibly do? If it's not the piping, and it's not the boiler itself and now it's not the gas line, what can it be?

    When Lochinvar rep came out to my house, he said although the installer did not install it per manual instructions, it works? Well, sure it heats my house, but I paid alot of money for something to make these noises that just aren't right.

    I also included a picture of my exhaust. The bigger pipes are the boiler. The smaller ones are the furnace. That never runs because we run the boiler through the coil in the furnace. How do you like the large icicle on the ground under it?

    I am not even working with the original installer because I do not have faith he knows anything about it. He made alot of mistakes and many have already been corrected, but if the whole things has issues, how many more need correcting? I have spent a couple thousand in labor now over and above the original install.
  • JUGHNEJUGHNE Member Posts: 7,861
    So the outside house 2 PSI regulator is set at 13" and then you have reg at each inside unit.
    It seems the outside reg should give you 2 PSI and then the inside unit reg drops to 13" and then the appliance gas valve reg sets it to what the input WC is required.

    Any problems with the forced air furnace firing?
  • ThunderThunder Member Posts: 8
    That sounds right...I just know he installed a new 2 pound regulator on the house. He said the pipe from the LP tank to the regulator is too small but can't replace at this time of year. He said he had it set to 13 and then when running the boiler the gas line tested at 11 - 11.5

    He put one on before the furnace too and said he wasn't worried in the least about that one. I don't run the furnace with gas because it heats the house through the coil that is heated by the boiler. We haven't tested the furnace itself since September, but it ran fine then.
  • IronmanIronman Member Posts: 6,142
    The boiler MUST be piped primary/secondary when used in multiple zones like you have - it's not. This probably accounts for the popping noise as it ramps up. The heat exchange is not getting proper flow through it which is crucial to ANY mod/con, not just the Loch. That's totally on your installer, not the manufacturer. Their diagrams are very clear in th installation manual which came with the boiler.
    Bob Boan
    You can choose to do what you want, but you cannot choose the consequences.
  • JUGHNEJUGHNE Member Posts: 7,861
    What is the btuh size of your boiler and also the furnace?

    Usually the first stage reg at the tank is set for 10 PSI. With that a 100' run of 3/8" OD copper will carry 161,000 btuh @ 1 PSI drop or 220,000 @ 2 PSI drop.
    So depending upon the length of pipe from tank to house and size of pipe (3/8" OD copper seems to be the smallest possible).

    Then from reading in the "Rego" and "Fisher Control" LP manuals they both state that any regulator installed inside the house must be vented to the outdoors with 3/4" pipe (Rego book) or 3/8 OD copper (Fisher book).

    Usually just a reg is installed outside the house and then pipe size as needed is installed to appliances.
    This might be 3/4" pipe size for those 2 appliances (and you may have more than 2?) from the outside reg to boiler as needed.
  • psb75psb75 Member Posts: 309
    I had similar very frustrating venting noises with a brand new Lochinv. Noble 80 install. The boiler was "fog-horning" upon start up and also when modulating down. I dealt with a lot of the same suggestions about incoming gas pressures, boiler gas valve adjustments etc. etc. All to no avail. I was dealing w/ tech support much of the time. Eventually the Loch. area regional rep was sent. He couldn't solve it when on site. Eventually Loch. had me change out two different motherboards that had been 'tweaked' by the regional rep and then sent to me. It had something to do with adj. fan speed during modulation to 'skip over' a particular speed where resonance was occurring. Eventually the problem was solved. The boiler was heating DHW and CH fine the whole time. Just making 'un-liveable' noise upon start up and shut down. Motherboards were provided by Loch. I was not compensated for my time--to make the homeowners happy. Many hours on the ph. w/ tech. support and onsite diagnostics on my part. I was not happy doing R and D for Loch. uncompensated. I moved on to another brand of boiler.
    The popping noise you are describing in the heat exchanger sounds troublesome as well. I like the suggestion to switch the plumbing to primary-secondary as Ironman and the install manual suggests.
  • HomerJSmithHomerJSmith Member Posts: 1,073
    edited January 15
    Ed, said that it sound like an ignition- combustion problem.

    I guess I should ask has anyone done a combustion analysis on the boiler? This is a stupid question, but today is my stupid day so I will ask--it's not an LP running with a Nat gas setup? gasp

    I don't see a place where a CO meter probe was inserted into the exhaust, so maybe it wasn't done.

    Also, I don't like to take a fitting off the exhaust of the boiler. I want at least 1' of vertical pipe before a fitting changes the direction of the exhaust piping.
  • ThunderThunder Member Posts: 8
    According to the new guy I am using it IS plumbed primary/secondary BUT NOT like it should be according to lochinvar, hence when lochinvar came out and said they would stand behind it because it's working BUT not done according to their specs. So far all they have stood behind are warranty parts that haven't fixed a thing. Honestly it the original installers mistakes and he's the one who should be paying to make it right. But instead I bypassed him because I don't think he has the knowledge so I've put out alot of money for labor. I was supposed to be getting a letter and a lochinvar contact BUT that's also going on a year and nothing yet. I don't want to slam lochinvar. I'm sure they are good boilers but I go a raw deal

    And yes combustion has been done several times. Once with the NEW guy (installer never did one). And then again after each gas valve replacement. It was off at first but dialed in right to the book easily and has stayed there even after new gas valve. Didn't need any tweaking

    There's a little red plug on the exhaust above boiler
  • IronmanIronman Member Posts: 6,142
    I can assure you that what's done there is not proper p/s piping, in fact, it bears no semblance of it.
    Bob Boan
    You can choose to do what you want, but you cannot choose the consequences.
  • HomerJSmithHomerJSmith Member Posts: 1,073
    The only red plug I see is in the flue above the Amana.
  • ThunderThunder Member Posts: 8
    Sorry. I went back down to check and it's actually up on the black part of exhaust. You can't see it from my angle of the picture. Its actually a little screw cap
  • tim smithtim smith Member Posts: 2,344
    I agree not primary secondary, not much work to correct. Have rep give you a simple line drawing for mods to correct and have original installer fix on his nickel. If he's any sort of stand up contractor he will correct. Sometimes you have to pay to play. He will learn what not to do when it costs money. 
  • tim smithtim smith Member Posts: 2,344
    Has anyone pulled blower and burner, check for loose burner screws or bad gasket. Any build up in heat x. Make sure igniter has not warped a bit? Have tech on site set up phone call with one of Lochinvar tech support supervisors, have him call b4 coming and arrange a time hopefully. Once they get to a lead tech it will go smoother.

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