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Corrosion on Peerless Boiler- Need a new boiler or not?

SFbird
SFbird Member Posts: 106
We had conflicting opinions from two plumbers. One says the corrosion on this leaking Peerless Boiler (steam heat, 12 unit building, on year-round) is too far gone and the boiler (12-13 yrs old, poor maintenance) needs to be ditched. Another says: Grind off the plate and replace it and the gasket, no problem. Look at the photo and give me feedback please!!!

Comments

  • meplumber
    meplumber Member Posts: 678
    Like most things. It depends.

    In my experience, replacing the plate and gasket is a 50/50 scenario. Sometimes it works, sometimes it don't. When the bolts break, then you have to try and use an EZOut to get them out. Then you have to re-tap the hole and all the while hope that you don't crack the cast iron.



    I don't do it unless the homeowner just can't afford to replace the boiler. Even if the tech is successful at replacing the plate and gasket, you are still on borrowed time with that boiler.



    This is caused by poor maintenance. If this was being properly maintained, then the technician could have replaced the gasket before the leak caused this much damage.



    Hope it works out, but I would say that it is time for you to plan for a replacement.



    Good Luck.
  • SFbird
    SFbird Member Posts: 106
    Sounds about right...

    Thanks so much! We also think CA is going to require low emission boilers on smaller multi unit buildings soon so we would be facing replacement in a few years anyway.



     Our old plumber who was doing our yearly inspections was not doing regular maintenance/blow downs on the system so this is what we have now....
  • SFbird
    SFbird Member Posts: 106
    another couple shots

    you can see into the tank.....arghh
  • nicholas bonham-carter
    nicholas bonham-carter Member Posts: 8,565
    peerless corrosion

    replacement sections could be available, which would save the burners and frame.

    when you repair or replace, try to find the cause of this corrosion. most likely, there is a steam or condensate leak, which has been masked by an auto-fill device on the boiler, which together with over-pressure may have caused the boiler to fill with a soup of carbonic acid.

    i doubt if pre-existing gas boilers will have to be changed out solely because of emissions, which are the same regardless of basic efficiency as a mod-con [if the burner is properly maintained].

    if it is 2-pipe, don't think you can convert to hot-water without re-piping and radiator replacement.--nbc
  • BobC
    BobC Member Posts: 5,317
    water consumption

    No matter if you replace or repair that boiler I would install a auto water feeder that gives you a readout of boiler water use. If I lived in the building I would go with a manual water feed and keep a log of water added (ex: 1/2" water added - per sight glass). Boilers really should be observed several time a week so problems can be detected EARLY.



    Bob
    Smith G8-3 with EZ Gas @ 90,000 BTU, Single pipe steam
    Vaporstat with a 12oz cut-out and 4oz cut-in
    3PSI gauge
  • Mark Eatherton
    Mark Eatherton Member Posts: 5,839
    Thats no small hole...

    I am surprised you are even able to generate ANY pressure. Must be kinda hot and steamy in your mechanical room during the winter eh...



    Can you repair it? As others have said, Maybe... but IF it DOESN'T work, then you are out that money PLUS now you've GOT to replace it. If it were me, I'd replace it, and be done with it. You also need to start and maintain a comprehensive maintenance program for this system, whether it is you, or someone else doing the work.



    High efficiency steam boiler eh... From 80 to 84 or 85%. I honestly don't know if they exist. Use to be a Canadian mod con steam boiler on the market, but haven't seen hide nor hair of it in a LONG time.



    ME
    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.
  • Greg Maxwell
    Greg Maxwell Member Posts: 212
    Coil Plate

    I agree completely with Mark, and meplumber. The problem is, the cast is probably too far gone to get a good seal on a new plate. And, I would advise against trying to replace a section, as it would run into the thousands, and you will still have to use the old burner, controls, etc. It used to be common to see sections replaced, but I doubt that you will find a contractor that would be willing to take the job these days.
  • nicholas bonham-carter
    nicholas bonham-carter Member Posts: 8,565
    Replacing sections

    When I mentioned that possibility, I meant all the sections would have to be replaced at once. As I said it can save the frame, and burner (if they are any good). It can also grandfather you in on certain code restrictions.

    High efficiency steam boilers are those which are correctly piped, and maintained, running on ounces of pressure, with ample main air vents, allowing the air to escape, at a back-pressure of a couple of ounces. Also with no leaks in the system, fresh water with excess oxygen is not being added to the boiler corroding it away.

    Check your boiler room for anything containing chlorides as well to prevent early failure.--nbc
  • SFbird
    SFbird Member Posts: 106
    Replacement Sections

    Okay, I just had two more contractors out here this morning, one says they have had luck with replacing the plate and gasket but at most that might just buy us a year or two and we are not really interested in that. We are leaning towards replacing it.

    The last guy who showed up is an old school, been in business in SF for 65 yrs kind of guy. He says, let's open it up, see how the inside looks and we could just replace that one section (of ten) if the rest looks okay and that with the proper maintenance, the thing could last for ten+ years. This is the first I have heard of section replacement from anyone who has been out here. Is it worth paying the guy for 3 hrs labor to just pull it apart and look inside and then decide?
  • SFbird
    SFbird Member Posts: 106
    Fresh Water

    Also,  Old School Plumber thinks the whole problem started because the gasket went, the thing was leaking and all the fresh replacement water caused the corrosion. Also, the goober who was doing our yearly inspections was failing to spot anything or do recommended maintenance.
  • SFbird
    SFbird Member Posts: 106
    Original Plumber Shows Up at our Door...

    Wants to make good by slapping a new plate on there. Told him we were not real happy with his oversight of our boiler so far. Said he would pull off the plate so we can look and see how far gone the tank is inside. Letting him do that much right now and that's it. Will post pics later so maybe you all can help me again....much appreciated. - maria
  • nicholas bonham-carter
    nicholas bonham-carter Member Posts: 8,565
    edited September 2011
    worth 3 hrs labor?

    whoever will replace the sections, or even install a new boiler will have to dismantle the present boiler first, so why not let him open it up for an inspection.

    do you know if the boiler capacity matches the radiation [edr]?

    while doing this, compare the supply piping and return piping with peerless's instructions--it must follow them at a minimum!

    assuming the piping, and the burner are correct, and in good condition, then i would replace all the sections, and let the rusty sheet metal stay as a grim reminder of the dangers of lack of maintenance, and the presence of an auto-fill left to it's own unsupervised devices.

    when you fire up the new one, disconnect the auto-fill, as it will hide any other leaks in the system in the first few months of operation!--nbc
  • SFbird
    SFbird Member Posts: 106
    Plumber Replaced Plate and Gasket

    He first pulled the old plate off and we assessed the tank. The opening showed it's original smooth edges so no apparent corrosion inside but I am not an expert so it just looked like a big old rusty hunk of metal to me but not "eaten away" rusty, if that makes sense. Plumber assured us that this repair would be good for two years and that he was going to stand behind his work. It really should have never gotten to this point, last annual inspection was done by him almost exactly a year ago this week and he knew this was a common issue with this series of boiler. Now we are left trying to decide how many years have been taken off it's life due to lack of maintenance for 12 years ( no monthly blow downs, no quarterly flushing or whatever else it needed).

    We have been told that we could go smaller. Current boiler is approx. 350,000 btu and with our radiator count we are told by one guy that we could go to 250,000 or even 220,000.



    If the current unit is maintained from now on, do you think it has some life left in it or should we still consider replacement?
  • magic repair

    only time will tell whether you will get the full 2 year life out of the boiler repair. after seeing your pictures, i am surprised that the area was clean enough to accept a new plate. luckily the weather is your area is not so severe as to give the plumbing a hard freeze, when the boiler fails.

    start planning now for the replacement, as far as calculating the size of the replacement, which apparently may be smaller than the present one. if this is one-pipe steam, make sure your main [not rad] venting is ample.--nbc
  • SFbird
    SFbird Member Posts: 106
    edited September 2011
    Pricing Out New Unit Now...

    Thanks for all of your feedback. We are going ahead and obtaining proposals for a new unit. The homeowners here are not opposed to spending the money, especially if we can get better efficiency with a smaller boiler and avoid a more severe failure.  Meanwhile, we are keeping a watchful eye on this repair as we are have our concerns.
  • sizing the boiler

    don't forget that the size of the boiler must match the radiator total [edr], as you don't want to be too big or too small. don't assume the previous boiler was correctly selected.--nbc
  • SFbird
    SFbird Member Posts: 106
    Boiler Sizing

    We have 27 radiators in the whole building. There are 12 condos, each about 1050 SQ. FT  with the same floor plan. No radiators in common areas (lobby, hallways). Each unit started out with 3 radiators, but over time (building built in 1929) some were removed. Most units now have 2, Only 4 still have 3 radiators and 1 has only 1 left. All units have one in the living room, column type, sized 26" H, 9 sections, single pipe. Dining room and bedroom radiators are all 26"H, 7 sections. Boiler runs all year but most people seldom use all their radiators, except maybe on a few super cold Northern Ca. days in Jan.-Feb. Boiler currently on timer,  starts up 2x a day, runs about 6:30 am-10am and again 4:30-10:30PM. Thermostat has a sensor in the lobby which is fairly useless as there is no radiator there, and one outside, near window of boiler room where it is sensing warm air blowing out from the boiler- obviously a pretty stupid set-up there!



    One plumber says we can go smaller but a different one says this (from their email, verbatim):

    "We did a radiator count and we

    size for the maximum load on the building.  If you undersize the boiler you

    will place more load on it.  If everyone had their radiators open on a cold day

    and then closed them with the system running you could flood the boiler.  The

    new boilers have less water content than the old boilers.  This could then lead

    to banging in the building.  I will speak with Al and get back to you."



    This contractor sent us a bid for installing a 399,000 Btu Peerless 64-08 steam boiler with an IBR rating of 1,010 sq ft of steam, for about 22,000 bucks.



    What do you think?







     
  • what to think

    either his communication skills or steam knowledge is lacking, so do you have another choice of installer? the boiler sizing is fairly scientifically exact. the edr for all the radiators are added up, so that the boiler can be matched exactly to the requirements.

    what sort of steam system is in the building--one-pipe or two-pipe? generally the valves should not be opened and closed whenever the occupants need heat. you really need a different control system, as it seems the system is overheating when on, and perhaps lagging behind at other times..--nbc
  • Mark Eatherton
    Mark Eatherton Member Posts: 5,839
    What I think....

    I think that there is a standing policy here at the Wall of not discussing pricing. Please observe that policy. With that said, we can't comment (legally) on the price without seeing a very detailed bid, and no one here really wants to see that.



    As NBC pointed out, sizing a boiler is a science, and it entails more than "counting" radiators. Radiators are rated in E.D.R. (Equivalent Developed Radiation in Square Feet of surface area) I'd suggest your HOA spend a few bucks and become very educated. Go to http://www.heatinghelp.com/products/Hot-Water-Heating-Books/26/80/E-D-R-Ratings-for-Every-Darn-Radiator-and-convector-youll-probably-ever-see and purchase the EDR book.



    Then also purchase "We Got Steam", and give yourself, your B.O.D., and possibly your residents an education about what it is that you have and how it is SUPPOSED to work...



    http://www.heatinghelp.com/products/Super-Deals/14/132/We-Got-Steam-Heat-PRO-PACK



    We here at The Wall are quite willing to help educate, but it would be a lot easier and you'd be much farther ahead by going through the process of education. This will allow you to reach a logical decision and allow you to generate a document telling the contractors what it is that you want/need.



    It is also recommended that you do an individual heat loss calculation (room by room) to make sure you have adequate radiation in place to counter the heating loads when it gets cold outside. If there is inadequate radiation, you might want to consider oversizing the boiler to handle the removed radiators just in case someone decides to put the radiators back on line. (doubtful, but possible)



    The reason for not commenting on pricing is numerous fold, the worst of which is a thing called "price fixing". No one wants to go there... The other reason is, that this site is frequented by people from all over the country (WORLD) and what happens in S.F. may not necessary be the same thing that happens in N.Y.C..



    Thank you for respecting the price rule.



    Pictures will tell a million words. These guys need to see the front, sides, back and top of the near boiler piping. Also, are there "issues" with the system (Hammering, hissing, clanking). If yes, these are not normal, and it sounds as if the contractor has just enough experience with steam to tell you to expect problems ( "This could then lead

    to banging in the building. I will speak with Al and get back to you"). He's been there, experienced that, and it is not the norm. They also may not know what needs to be done to resolve these issues. Once you've read We Got Steam, and some of the other books available here, you too will be able to reasonably make decisions.



    Lastly, if you take this issue over to the Steam section, you might get some better responses. Some of the folks who read the Steam section rarely wander over here to The Wall.



    ME
    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.
  • SFbird
    SFbird Member Posts: 106
    edited September 2011
    Sorry!

    Hey, sorry about the mention of pricing; I did not delve too deeply into the posting guidelines as I sort of stumbled upon this forum while in sheer panic mode when we first discovered the corroded boiler plate. I will do some reading as you suggested (okay?) as I admit I am fairly clueless and I can only go on what the contractors who have been out here tell me. I will post more pictures too.



    Yes, it is a single pipe system and, yes, we had had clanging noises in the area close to the boiler room when the boiler starts up. It stops after the thing is fully running. The reason we discovered the corrosion was because we had hired a new heating guy to do maintenance, re-grade some return pipes that we think got moved around during a seismic retrofit about 6 years ago and a few other things that he recommended. This all began as an effort to resolve the water hammer. He suspected we had a leak on the boiler vessel and he found the hole.
  • SFbird
    SFbird Member Posts: 106
    P.S.

    The guy that discovered the corrosion is not the same contractor who sent me that email I quoted. He is actually still working on getting us the boiler size requirements according to what (I think) is more like the formula you have suggested.
  • Mark Eatherton
    Mark Eatherton Member Posts: 5,839
    No problem...

    We're here to help, but as contractors have to be careful what we say about pricing.



    Thanks for understanding.



    An educated consumer is a smart and good consumer in my book.



    ME
    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.
  • bill_105
    bill_105 Member Posts: 429
    Steamless in San Francisco?

    Sounds like a movie. Steam is a different animal. Bay area steam specialists must be few and far between. Funny how you ended up on the best site for your opera.

    BTW- where in SF is it- grew up in Millbrae.
  • SFbird
    SFbird Member Posts: 106
    SF Steam Drama

    Marina District, here! I might try digging through the old association documents to see how they settled on the current boiler size.....it was replaced before we bought our condo.

    I can post the findings of the evaluation we had done that made us decide to bring the new guy out to do the work in the first place ( the guy who found the leak), if that might help shed any light on this? His report was on dealing with the noise issue; now we have this whole new drama.
  • SFbird
    SFbird Member Posts: 106
    Other options are under consideration....

    Yes, nbc, we are waiting on three other proposals. I am leaning towards the guy who found the leak to begin with.



    That email I quoted earlier is from a "general manager"  (which might mean just front office staff, not the technician Al who was out here) so maybe she was not the best person to ask? They are a well-established, reputable company and are listed on the Peerless website for installation/service.  The reason it raised a red flag with me is that the size they recommend is larger than the current one. We never had a problem with units being too cold here. The water hammer thing seemed to start after we had construction going on in the garage.



    The guy who found the leak seems to have his **** together, based on his evaluation of our water hammer problems. He is currently working on figuring out the new boiler sizing. Hope to have more info after the holiday weekend is over. I resorted to going online because we got such differing opinions on the corroded plate and I had no idea who to trust and I guess I found a great resource!
  • Mark Eatherton
    Mark Eatherton Member Posts: 5,839
    I got blown up in Millbrae....once.

    Got called out to a hotel chain I use to do crisis management for.



    Seems they had a 3.5 mill Ajax boiler that was "lighting off hard". The boiler was in a remote building. As we approached it, I could see heat coming out of the stack, and knew it was lit. The Chief Engineer and his assistant were with me, and I heard the kid say "It's lit, its OK to go in..." As we approached the mechanical room door, I noted that the spot welds were all broken lose on the steel door and rust had not yet formed. "That's new", the chief said.



    We opened the double door and walked in. The boiler was purring along just fine (laundry hot water load was keeping it running). Shortly thereafter, it shut down on high limit, and the chief and his assistant started moving towards to door. I was asking them what had transpired, and heard the stories about who'd been in and done what to it when it went for another trial for ignition. I automatically start counting in my head, and if I don't hear ignition in 5 seconds, I start looking for shelter or an exit. As I turned to go out the door, dumb and dumber are standing with their mouth agape in the exit door. I said RUN. As the three of us hit the door, the boiler finally lit, and there was fire coming out of every orifice of the boiler, including the draft hood and the roof vent. The concussive explosion threw the three of us out of the boiler room and into the parking lot in a heap of humanity. As we were lying on the ground, I heard the assistant say "It's lit. It's OK"....



    Come to find out that the gas valve was a 2 stage valve, and the first stage had failed. Someone bypassed the first stage, so the boiler was trying to light off on the second stage. Only problem was, the pilot assembly was connected to the first stage, so the combustion chamber would fill completely with gas before it would "light off HARD".



    I dropped a new gas valve into place, and undid the knuckleheading to the wiring, and things got back to normal. Was back in Denver before 9:00 PM that night...



    Some peoples kids, I'm telling ya...



    ME
    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.
  • SFbird
    SFbird Member Posts: 106
    new pics of repair job

    When I read stories of boilers exploding, I wonder how long our patch job is going to hold. My husband tells me that it won't "explode" if it failed, we would just have a giant steam geyser.



    Still waiting on proposals. Couple of plumbers are basing the size of the new unit on the number of radiators that the building was built with "in case" some owner wants to replace one that is missing now. Not very likely.
  • band-aid for boiler

    the piping is nicely insulated, but maybe not correct in the lack of a hartford loop, which could void the warranty.--nbc
  • bill_105
    bill_105 Member Posts: 429
    Maria

    Keep searching for a good steam guy. Replace it. There has to be one in the bay area. Maybe  A.F. could weigh in. With my luck it's the guy's ex-wife trying to get back at him!
  • SFbird
    SFbird Member Posts: 106
    NEW BOILER INSTALLED

    Hi again! Well we just had our replacement boiler installed last week (Peerless 64/65 Series). Can you all take a look at the near boiler piping ( new ) and see if it looks "kosher" to you?



    We are getting lots of steam hammer happening in the radiators now. We had some with the old boiler but it is now pinging all the way through the heating cycle, except when it is at the very end. All steam vents are new, valves replaced within last 4 years....

    The last pic shows a return pipe that I am confused about ( sorry I have no clue about plumbing!) isn't this supposed to be pitched down toward the boiler? As it stands, it runs through our garage nearly flat in some areas and then up a little and down again....or does that not matter if it is below the boilers water line the whole way?

     

    Do you guys recommend flushing all the risers and even blowing out the individual radiators when you do a boiler replacement?
  • SFbird
    SFbird Member Posts: 106
    Also, does this look like a Hartford Loop to you?

    I am comparing our piping to the Peerless diagrams trying to figure out what is what here and I am getting brain damage. Any feedback would be appreciated.
  • Rod
    Rod Posts: 2,067
    New Boiler Problems

    Hi Maria-

    Congratulations getting the new boiler!  Usually you don't have to clean the steam piping as it was constantly being "steam cleaned". However sometimes the lower piping "Wet Return" needs to be replaced.  You boiler piping doesn't look too bad though due to the insulation being in place it is hard to tell if the piping is the correct size.



    A couple of questions: 

    1. What is the maximum pressure that the system runs now?  (It should be less that 2 PSI and a lot of systems run far lower)

    2, When the boiler is making steam does the waterline in the sight glass bounce a lot?

        if so, how much?   (A bit of bouncing -1/4 inch up, 1/4 inch down is normal)

    3. When the boiler is operating, does water condense on the inside of the sight glass above the waterline?



    I would question whether your boiler has been skimmed as it doesn't look like the skim port has been opened. (see attached picture and  Page 45 in the Installation manual) Normally a short pipe nipple and a pipe cap are attached to this boiler port to facilitate skimming. New boilers need to be "skimmed". This is usually performed just after the boiler has been installed. Skimming needs to be done as otherwise the boiler maybe producing what is called "Wet Steam" which can cause the problems you describe.

    Peerless gives skimming instructions on page 33 and 34 of the IO&M manual which you can get at this link if you don't already have a copy.

    http://www.peerlessboilers.com/Products/CommercialBoilers/Series64/tabid/122/Default.aspx#dnn_relateddocuments



     I've also attached a write up on skimming for you.

    - Rod
  • SFbird
    SFbird Member Posts: 106
    Cleaned but maybe not Skimmed...

    Thanks so much Rod! I am going to check on the items you asked about and get you some answers later. 



     I had heard about the skimming process but I will ask our contractor again and read what you sent. We do have the Peerless literature here. I know he flushed out the vessel and used some sort of soap flake stuff to clean out the manufacturing oils but I don't know the actual "process" he used (only that we had an interesting odor coming through the steam vents for a while). He did this before the thing was really running for any meaningful length of time so I don't know if it needs to be skimmed again now. It has been running for two days at this point ( kicks on twice a day for about 4 hours).
  • bill_105
    bill_105 Member Posts: 429
    How about this?

    Doesn't the relief valve need to be vertical, even with a steamer?

    Well she's from S.F. so I had to say something!
  • SFbird
    SFbird Member Posts: 106
    edited September 2012
    More Information + Observations

    So I was just downstairs observing while the unit was going through a few cycles. Seemed to be firing up every 4-5 minutes.

    I took photos of the gauges since I am (of course) somewhat confused as to what they are all. Anyhoo....this is what I can tell you:



    "Cut In" set to just below 2

    "Internal Syphon" reads 5PSI when burner is fired, drops to 2.5 after it goes off

    "Main Pressuretrol" is set to about 8PSI (is that the cut-off pressure level?)



    The sight glass water drops way down when the burner is lit, lots of bubbles fill the empty space. Water stays pretty low (fluctuates a little) and then when the burner goes off it rises, eventually filling ALL the way to the top after the burner goes off .



    Thermostatic controls are reading "E2" on two out of three.



    We are getting pinging and clanging pretty much every cycle. Radiator in my unit, third floor sounds like a surge of steam hits it and then some jangling/ pinging sounds. My other two are turned off but still getting noise near the connection in the floor.

    Sorry I can't figure out how to rotate these pictures so they are easier to see:
  • nicholas bonham-carter
    nicholas bonham-carter Member Posts: 8,565
    edited September 2012
    San Francisco boiler problems

    From what you say, it seems that the pressure is much too high. My system of 60+ radiators, with a boiler of 1,050,000 btu operates in the 2- 8 ounce pressure range, and heats up the building very well. The system has lots of main vents, which remove the air so the steam c an enter the pipes, and radiators. There must be adequate main vents (usually on the dry return coming back to the boiler). My system has 18 of the biggest vents available, so you need more. Your system was originally designed to be quiet, even, and economical, so the task is to return it to something close to its original state of operation. A vaporstat, and good low-pressure gauge will be needed to keep the pressure down in the ounces, verified by the gauge ( my gauge is 0-15 ounces!)--NBC
  • SFbird
    SFbird Member Posts: 106
    edited September 2012
    Thanks Nicholas!

    Do you think I should post in the Steam section as well for more feedback?

    Our contractor  said something to my husband about "water in the lines" that was there because some had flattened out from their original pitch due to an earthquake retrofit we did about 7 years ago. His rational for operating at this pressure level was to drive the steam through in spite of any water that was hanging out in the lines. All this sounds sort of idiotic to me ( although I am not a plumber so maybe I shouldn't be so harsh) and not really a good solution. Obviously opening up all the walls to check every line is not optimal either. I am going to ask him to run the unit at a much lower pressure and see what happens. Do you have a starting point given what you can see from the pics of our system? How low can we go with these gauges?
  • Where to post

    Yes, please do post on the steam section for any other questions, and there will be even more answers to your questions!--NBC
  • JStar
    JStar Member Posts: 2,752
    Pressure

    Steam should never "force" anything. I needs to be a very gentle process.



    Set the Cut In pressure at 0.5 and th differential wheel at 1 psi. That will be a good start.
This discussion has been closed.