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combustion analysis

drhvacdrhvac Posts: 189Member
In the market for a combustion test meter. These things are expensive. Is anyone familiar with the fieldpiece SOX2? Its much cheaper than alot of the meters and seems to do what I need it to do.


  • icesailoricesailor Posts: 7,265Member
    Combustion Analyzers:

    You get what you pay for.

    If you buy a cheap analyzer, you may get cheap results.

    I never heard of the one that you are contemplating.

    Bacharach is having a deal now Testo may also be having one Wholer never seems to have one.

    Cheap tools go with cheap jobs.
  • SpeyFitterSpeyFitter Posts: 421Member
    Do NOT

    Cheap out on a combustion analyzer. If you're a contractor (assuming you are) you should be billing for everytime you use the analyzer - something along the lines of an instrumentation or combustion analysis fees. Not only to help you recouple some of the investment into these precision devices, but also to help pay for future calibrations and repairs.  I've used a cheap analyzer in the past and I got what my company paid for. Spend a bit more and you'll get more.
    Class 'A' Gas Fitter - Certified Hydronic Systems Designer - Journeyman Plumber
  • drhvacdrhvac Posts: 189Member
    which one?

    Ok, that's what I thought, you get what you pay for. What models do you recommend? How is the Testo 360? And how do you guys incorporate higher fees? When doing a routine cleaning, you give the customer the option to have the combustion test for an extra cost?
  • tim smithtim smith Posts: 2,275Member
    Re: analyzers and options for clients

    It is not an option because it is part of a safety check besides energy efficiency. You have to incorporate the costs into you hrly fee.  Make sure to count on probably 300 - 500 yr for maintenance repair.  I just sent 3 in for service, 500 each for repair. Thanks T....o       Tim
  • Jean-David BeyerJean-David Beyer Posts: 2,620Member
    As a homeowner, it seems to me

    that for a routine annual service, the combustion analysis should not be

    optional: it should be included in the fee for that service. I do not like it hidden in the hourly rate, though. I think the fee for a routine annual service should be $xxx, where xxx may be different for different systems. For a first-time call, this should probably have to be time and materials (including overhead and profit) because the contractor would not know what is required until he has seen it. But I have never run a service business, and do not know the psychological realities of dealing with customers.
  • drhvacdrhvac Posts: 189Member
    not that easy

    I strictly work on gas units. When I look in the local advertisements, all I see is my competitors advertising furnace services between $35 - $89. And in there advertisement the home owner gets a 21 point tune up, its all a bunch of bs, check belt, check t-stat, check this, check that. None mention combustion analysis, because none of them do it. Its hard being the one guy going in there and saying your going to service there furnace for $200 - $300 when all they see is the prices above. And homeowners all say how they will pay the extra money to have it done right, but most of them are looking at the bottom line which is the price.
  • clammyclammy Posts: 2,217Member
    ombustion anz

    drhvac,i fully understand where you are coming from,i work on oil,gas and some LP and it is tough .I also see the ads you speak of .i took the plunge about 3 or 4 years ago and brought a e instruments CA .Each year i take a service contract cost about 500 bucks but gets it certified and fixes what ever is broken.I also understand that it is a tough sale with HO's being your the only guy talking about testing while every body else blows it off.The field piece unit is pretty much junk and in my view in not even close to any real CA a waste of money in the long term .If you don't want to spend a whole lot take a look at TIF they make a couple .I have a buddy who's company uses them and they are happy with them but i do believe that they are not cert, but the sensors are field replacable a plus.I gave up charging for CA testing got tried of the yelling and screaming over the extra charge so  i just charge more on jobs where i will be performing a combustion testing like increasing my rate .As whole my CA has not been a money maker more like a expense at least around here being different and talking about combustion testing on gas equiptment is a albatrose there are only 1 or 2 guys i know who do it and even fewer who would buy one and that includes most of the bigger companies they all state that it done at the factory and is unneccesary for field testing or adjustment .Very touchy and funny subject espically amoung those who blow big buks on flyers ,mailer and yellow pages adds and nothing on test equiptment or read glasses .Sorry for the rant but it burns my bottom.Peace and good luck clammy PS keep fighting the good fight and stick to your guns espically on testing .I know i sleep good each nite
    R.A. Calmbacher L.L.C. HVAC
    NJ Master HVAC Lic.
    Mahwah, NJ
    Specializing in steam and hydronic heating
  • Jean-David BeyerJean-David Beyer Posts: 2,620Member
    I have seen those adds too.

    When I get them in the mail, they go straight to the trash.

    When they cold call me, I hang up. I do not read the throw-away newspapers where their ads seem to appear.

    I have read the annual service requirements on my boiler and estimate it would take me half a day, if I had the proper equipment. I have watched two different contractors do mine. The first one refused to do most of the steps required and said he was only allowed 15 minutes to service a gas boiler. That is why I dropped that contractor and went to the second.  They send a technician and a helper. It takes them between 1 1/2 and 2 hours depending on what they find. They come prepared with a new igniter, a full gasket set, plus the usual stuff on the truck. I do have to be firm with them to get them to bring the combustion analyzer, and show them where the access to the exhaust stack is to insert the probe.
  • Jean-David BeyerJean-David Beyer Posts: 2,620Member
    The money some save by skipping combustion analysis

    should be spent on increasing their liability insurance. There could be quite a large judgement against the person servicing the equipment and killing the homeowner and his family because of CO poisoning. 
  • kcoppkcopp Posts: 3,324Member
    I have a Wohler 335...

    petty good unit, although I am told that it is discontinued because it does not work on Biofuel oil... not a problem for you. It is in line w/ what other have said about cost and annual service. I have had it about 2 years. I can't imagine not having one now. I just used it to set up my first conversion burner and I would have been completely screwed w/o it. Use that to your advantage... advertise that if they don't do the combustion test they put their customers @ risk.
  • tim smithtim smith Posts: 2,275Member
    Re: analyzer fee and hourly rate

    I never implied it would be buried in hourly fee it is just part of the makeup of hourly expense as all expenses in our buisiness are. Insurance is x, office expense x, vehicles etc etc etc.  That is what makes up our hrly charges.
  • SteamheadSteamhead Posts: 12,933Member
    Without an analyzer and the know-how to use it

    you're naked in that boiler room. That's not a pretty sight :-0

    And this is the usual result:
    All Steamed Up, Inc.
    "Reducing our country's energy consumption, one system at a time"
    Steam, Vapor & Hot-Water Heating Specialists
    Oil & Gas Burner Service
    Baltimore, MD (USA) and consulting anywhere.
  • icesailoricesailor Posts: 7,265Member
    Combustion analyzers/Liability:

    Where I work, there is an oil company. No one in the past, ever used Combustion analysis (CA) ever, except me, and my old Bacharach wet oil kit. A friend had an old Lynn kit I could use but every time I went to use it, it was broken and needed to be sent to Lynn. That's why I bought my Wet Kit.

    Today, this oil company does a large percentage of the oil servicing. When they started doing it a few years ago, they bought CA's for every truck and spares for when being serviced. The insurance company told them that if they didn't have proof positive from an electronic instrument that showed that when they left after servicing the equipment, and there was a freeze up or soot up, they would be on their own. Hence, the CA's. They leave a print-out of the combustion analysis results, stapled to the card of what they did. And a copy in their files for confirmation. Strong incentive to buy a CA. The LP suppliers, only one does service and repair, have no CA's.

    I bought my Bacharach "Insight" recently because I have so many customers now with LP gas. And never been tested. I drained a customers house Thursday and found the 2004 vintage HTP Munchkin 140 locked out on F10, going out more than 4 times in one run cycle, I've never serviced this boiler, I didn't install it. I did the indirect and plumbing, a "Heater" did the boiler and air handlers. I reset it and the vapor coming out of the exhaust had an odd color. I put my "Stick" in the outlet and had 380+ PPM of CO. The boiler came as Nat. Gas and had no conversion sticker on it. It had black electrical tape covering the air inlet to increase suction through the orifice that was too big. Someone found this as a solution I am told. Another project.

    When you take your vehicle to the dealer, the first thing they do is hook up the computer to do a diagnostic. They won't even consider working on the vehicle without the diagnostic test. And they charge you for it. First thing on the bill. No one complains.

    Those pictures that Steamhead posted, some of those are "Cold Start" oil boilers, but all either not serviced regularly, or else the "Brush And Buff" crowd was servicing them. "They did such a nice job, they even wiped the dust off the transformer." So says the customer.

    It takes a lot of time to clean and service this equipment. And gas is just as bad. You just can't see how bad it is. unless you CA it.

    My "Insight" has all field replaceable sensors that are already calibrated from the factory. A program to replace them, and you can re-calibrate them yourself with your laptop. If it works as advertised, it is one cool tool.

    Nice representative photos Steamhead. Thanks for posting.

    I've spent four or five hours cleaning up a mess like that where the unit had been serviced in an hour for years "by others".

    I've seen "Cold Starts" that do that in a year, no matter what you do to it. I've seen "Warm Starts" go five years and look not a lot different than when it was cleaned the first time.
  • croydoncorgicroydoncorgi Posts: 83Member
    edited December 2011
    Essential for H/E gas boilers

    A CA / Flue Gas Analyzer is essential for the great majority of existing high-efficiency gas burners (except the very few with automatic adjustment - and even those shoud be double checked with a separate instrument).

    If you don't get the gas / air mix spot-on, efficiency will go down and / or boiler life will be shortened due to excessive solid combustion products, hot-spots etc.

    And often a combustion quality check is a valid alternative to stripping down the burner assembly on most machines much of the time.  If it ain't broke don't fix it.  With reasonable gas quality and the burner set up right, a burner should be able to go 2 or even 3 years with no need for cleaning.

    Reading here about (eg.) Viessmann heat exchangers needing frequent cleaning with heavy duty chemicals sounds worrying.  Are they in fact set up right?  Or is piped gas in the US full of sulfur or whatever?
  • drhvacdrhvac Posts: 189Member

    You guys convinced me. I'm looking in to the Testo 327, anybody familiar? Question. If I had a 95% efficient gas furnace and hooked one of these meters to it, and found that numbers were off and it had to be adjusted. How do you make the adjustments. The fresh air is fixed because it is coming from the outside. The only thing that is adjustable is the gas pressure, right? What else is adjustable on these units to change the co2 and o2 numbers should they need adjusting?
  • Tim McElwainTim McElwain Posts: 4,231Member
    Before you start testing

    you need training on gas/oil combustion and how to properly use the analyzer. As for adjusting gas Mod/Con boilers and furnaces you need training on each manufacturer's unit as they are somewhat different. These are not your grandfathers old equipment anymore. 
  • billtwocasebilltwocase Posts: 2,385Member
    Testo 327

    Can't beat em. Like any other necessary tool relevant to your trade, you can't try to bill separate. The tester is checking your work and adjustments. It is a necessary evil, and should come out of your mounting profit account. i have seen guys charge new tools to an install, and that is just not right in my eyes. If tou are charging a customer for something, then it should be left there for their future use.
  • icesailoricesailor Posts: 7,265Member
    Tool Charge:

    If you need to chop up a floor, and you don't own a $1.000.00 rotary hammer, and you go to the local tool rental place and rent one for the day for $100.00, do you eat the $100.00 or do you charge for the tool rental. If you bought the $1,000 drill so you didn't need to go rent one, and the good one was out and the junk one was available as usually happens when you rent, don't you think you should get paid for the tool?

    When you go to the auto dealer, you don't expect them to give you the $2,500 analyzer that they charged you $100.00 to diagnose why your "Check Engine Light" is on.

    Anyone that says that they can do it without instruments and do it by eye, is lying to you and themselves.
  • billtwocasebilltwocase Posts: 2,385Member
    tool rental

    If you need to rent a tool or something for that particular job, that is a charge that you pass on to the customer. If you buy it, and will use it on countless other jobs, I personally wouldn't charge for that. I own my own jack hammer/drill, and I need it to make money. Without it, they will hire someone who does. It's like charging to use your screwdriver on a job. It's part of your labor charge
  • icesailoricesailor Posts: 7,265Member

    That's the point.

    If you rent it, you charge for it. If you own it, you give it away. What's wrong with this picture?
  • Jean-David BeyerJean-David Beyer Posts: 2,620Member
    I do not know about gas furnaces, but for my gas boiler...

    I read the installation manual, and it tells me what to do. I would not diddle with the gas pressure because that is the regulator on the gas meter, and I believe the adjustment screw there is sealed. On the boiler, the gas comes in and goes to the gas valve connected to a venturi that mixes the gas with he air. The gas valve is set so if there is no air flow, no gas comes out, and the more flow, the more gas you get. In other words, it runs like an old fashoned gasoline carburettor. There is a little blower in there that pulls in the air; the speed of that blower is controlled by the system electronics board that considers outdoor air temperature, boiler supply water temperature, and g.o.k. what else. There is a mixture screw that can be used for adjusting the thing. Perhaps it is like an idle screw.

    If I had a combustion analyzer, all I would have to do is set the boiler to high fire, and adjust the mixture to get the right levels of CO and CO2. Once I got that, I would set the boiler to low fire and check that I got the right levels of CO and CO2 there also. The only trouble is if I could not get the right levels at both high fire and low fire. Since I have a professional come in to handle this, I do not have to know. I wish the manual did tell me, so I could check on the professional.
  • drhvacdrhvac Posts: 189Member
    problem with 327

    I'm really getting to like my combustion meter, and you guys were right, it really gives you piece of mind when you leave the job knowing everything is working the way it should. I can't believe I went as long as I did without it. My meter was working fine until yesterday. The O2 reading is staying at 21% during the test and not budging. It was working the way it should by going down to around 8% after the burner fired and held. I checked the condensate drain plug for tightness, and I made sure the hoses were connected to the filters ok. I think the problem happened after I changed the order the display was in, but that shouldn't cause this problem I think. Anyone with the Testo 327 have any idea what it could be?The meter is only a week old.
  • furnacefigher15furnacefigher15 Posts: 508Member
    stuck at 21%

    Couple things

    1- hose connections( filter, probe, etc..)

    2- pump not running (maybe in hold or stop mode)
  • KCA_2KCA_2 Posts: 303Member
    What about...

    Using an analyzer on an atmospheric boiler?  What are you able to do?

    :-)  Kca
  • SteamheadSteamhead Posts: 12,933Member
    It will verify

    whether the burners are operating properly- in addition to checking gas pressures, clocking the meter etc.

    I once tested a recently-installed atmospheric gas steam boiler that had all the hallmarks of a hack job- copper header, no main vents etc etc. CO was about 600 PPM air-free. Turned out one of the burners had somehow gotten knocked out of alignment, and the flame was impinging on the cast-iron. I seated it properly and that solved the problem.

    If you don't test, you don't know!
    All Steamed Up, Inc.
    "Reducing our country's energy consumption, one system at a time"
    Steam, Vapor & Hot-Water Heating Specialists
    Oil & Gas Burner Service
    Baltimore, MD (USA) and consulting anywhere.
  • KCA_2KCA_2 Posts: 303Member
    I've got an atmospheric boiler

    that has a CO level of 2500....  Nothing to adjust...  Manifold is at 4....  Got me stumped..
  • drhvacdrhvac Posts: 189Member
    figured it out

    why my CA was staying at 21% even when blower came on. There are 2 settings on the meter, oxygen % & oxygen air %. I had it set on the Oxygen air setting which basically is reading the Oxygen in the surrounding air. The Oxygen % is the correct setting.
  • drhvacdrhvac Posts: 189Member

    KCA manifold at 4, I'm assuming your meaning the manifold pressure. Most manufacturers recommend 3.5, so that is 1 thing that would effect the CO. What about combustion air, alignment of the burners, or flue piping size?
  • icesailoricesailor Posts: 7,265Member
    Combustion Analysis-Gas Type:

    Are you using Natural Gas or LP? I see gas burners develop CO like this that come Nat. Gas that haven't been converted to LP.

    I found a Munchkin the other day that had never been converted to LP and was installed in 2004. No conversion stickers and inspected. It hasn't run properly since the install. I didn't install it.
  • KCA_2KCA_2 Posts: 303Member
    It's a Laars

    Boiler and they recommend 4" at the manifold for NG...  The draft is .01 and Combustion air..  is fine with (1) 7" high to the outside and (1) low to the outside..  The boiler is 160000BTU input..  I'm at 7000' ASL..  Alignment of the burners....  Seem factory set OK..            I have a Bacharach Fyrite Pro meter...  Measures Excess air..  CO2 etc..

      Any help is well appreciated...  :)
  • Mark EathertonMark Eatherton Posts: 5,844Member
    edited December 2011
    Start with the basics...

    Is it derated for the actual altitude of operation? It should be derated 4% per thousand foot above sea level .

    4" w.c IS the proper setting, assuming that the proper orifi are installed.

    Are the burners clean? You have to pull them completely out and brush and vacuum them to make certain they are properly aligned on reinstall.

    Also, the heat exchangers on this style of boiler is extremely susceptible to fouling and plugging,and although you may have the necessary draft at the vent hood, but not within the combustion chamber . Also watch for a lack of combustion air. Blocked or partially blocked HXers are usually also seen with a sign of rollout at the combustion air intake zone of the burners.

    The HXer can be clean insitu but may have to be pulled and taken for a ride to the car wash... Depending upon how much abuse it has seen (dryer lint is killer).

    Clock it at the gas meter to make sure it is properly derated, clean the burners and the heat exchanger and you should be good to go.

    Good luck Kenny and get back to us with the final results.

    It's not so much a case of "You got what you paid for", as it is a matter of "You DIDN'T get what you DIDN'T pay for, and you're NOT going to get what you thought you were in the way of comfort". Borrowed from Heatboy.
  • furnacefigher15furnacefigher15 Posts: 508Member
    teledyne co levels

    If this boiler was sooted at some point, there is a good chance the burners are warped, causing wild flame characteristics.

    Pull the burners and inspect. The warping is hard to see, but look at the slotted openings in the burner, they should all have same amount of gap and curvature, if they don't, that is the likely problem.

    Good luck
  • drhvacdrhvac Posts: 189Member
    back to original topic

    What effect does to much excess air have on the combustion process, and how would you lower it if you had to much? Does it ever get to the point where to much air could create CO?
  • Mark EathertonMark Eatherton Posts: 5,844Member
    You really should take a good class....

    From either TIm McElwain, or Jim Davis.

    Excess air will carry off the heat you are paying for, and can be adjusted in a number of ways, but will require significant modifications to the equipment in order to bring the draft under control.

    Excess air can quench the flame, which can produce excessive CO in the flue gas stream.

    The more I learn about the combustion/draft control process, the more I realize I have a LOT more to learn and apply in the field...

    Good for you for taking the right steps to learn the whole process. Owning an analyzer is only part of the job. Understanding, and interpreting the results and knowing what to do to change parameters is just, if not more, important.

    It's not so much a case of "You got what you paid for", as it is a matter of "You DIDN'T get what you DIDN'T pay for, and you're NOT going to get what you thought you were in the way of comfort". Borrowed from Heatboy.
  • Plumdog_2Plumdog_2 Posts: 873Member
    Sooted or clogged Heat Exchanger

    Is a likely cause. Sometimes inspecting the bottom of the Heat Exchanger with a mirror will lead you to believe that it is not too bad, but opening the top will reveal clogged flueways. It will likely "Roll Out" pretty soon. I would clean it, verify correct orifice size, manifold pressure, and primary air openings. Blow out or wash the burners. Lint buildup will throw off your burn. After a good cleaning the CO readings usually drop way below 100.
  • Kal RowKal Row Posts: 1,518Member
    love my Bacharach 24-8251 FYRITE INSIGHT

    i bought it on ebay - be careful - this one was actually sold to me by jonstone supply - all the big houses do this now to increase sales - (if u cant fight them join em)

    a quick search will show 1200 to be the going rate for the analyzer and printer (a must have) - i am very happy with the unit and - they have a good sensor replacement subscription program

    the next big diagnostic thing i absolutely need to have is an infrared thats gona cost me...
  • Kal RowKal Row Posts: 1,518Member
    love my Bacharach 24-8251 FYRITE INSIGHT

    i bought it on ebay - be careful - this one was actually sold to me by jonstone supply - all the big houses do this now to increase sales - (if u cant fight them join em)

    a quick search will show 1200 to be the going rate for the analyzer and printer (a must have) - i am very happy with the unit and - they have a good sensor replacement subscription program

    the next big diagnostic thing i absolutely need to have is an infrared thats gona cost me...
  • furnacefigher15furnacefigher15 Posts: 508Member
    like mark said

    Too much excess air can lower flame temperature resulting in less heat output per unit of fuel being burned.

    The primary object of combustion analysis is to prove safe operation of the burn, meaning acceptable CO production (ideally 0 ppm, but AGA accepts 400ppm max)

    Secondary purpose, and for me of almost equal importance is to get the burn as efficient as possible. And, the meter saying X% efficient is not what I mean. An efficient burn is one where the excess air is as low as possible w/o producing CO. Every burner will be different, but each type of burner has general targets to meet, if you don't have a spec provided by the manufacture.

    Adjusting excess air depends on what type of burner you have. The easiest to manipulate are power burners (like oil burners), and the most difficult are in-shot type (like on most modern gas forced air furnaces)

    Usually too much excess air will not create CO, but in certain situations, it can.

    CO is a byproduct of INCOMPLETE COMBUSTION. Incomplete combustion can occur for a variety of reasons.

    One of the most common causes of too high of excess air is excess draft. And causes of this will very dependent on type of appliance and category of vent.
  • icesailoricesailor Posts: 7,265Member

    I bought mine from my Wholesaler for the same price you got it from on E-bay. I hope that you don't have a problem with it because E-bay is a bummer on Warranty service.

    Mine came with the printer, the inlet hose. printer paper, filters, the program for transferring data to a laptop and a DVD on how to operate it. Including case.
  • KCA_2KCA_2 Posts: 303Member
    How about adjusting

    It on an Atmospheric Boiler?  There doesn't seem like there are a lot of adjustment options.. 

      :-)  Kca
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