Heating Help

straighting out a system ,what to do?

@ February 3, 2012 7:55 AM in straighting out a system ,what to do?

I was asked to take a look at a radiant/ heating  system which was not performing when temps reached about 10 f and could not hold temp.There is 4 radiant zones 2 hi temp base and a idwh.2 zones are staple up with extruded plates and  2 in a slab.The staple up [late system that i was able to see did not seem to be installed correctly plates where 4 inch wide and screwed tightly to the sub floor except right next to the beams and did not run the length of the  bay ,they had left a 3 inch air gap and used r19 foil insulation and did not insulate rim or the end of the bays .The radiant in the slab was only insulated with bubble wrap and the back side of the home is a walk out .The staple up will not meet the lose and it seems while there that even after the slab is heated to about 78 and the boiler is running hi temp 180 when the slab is then turned on the boilers water temp drops to about 140 and will not recover no matter how long it runs but if i shut the slab zone and crank every thing up the boiler will get right up to 180 .Could the slab be sucking that much heat due to no insulation and causing the whole system to under perform .I did do a heat lose and the boiler is sized correctly but with the slab not being properly insulated the system under performs .Other reasons this system does not perform properly after 2 repipes by supposed pros is it still is not piped properly .Its a weil mclean ultra mod con 105 .The primary secondary was not piped correctly ,no outdoor reset nor indirect sensor .All radiant is done with fixed mixing valves and a pump piping arrangment that left us wondering who the hell did this they installed a pump on the mix port pumping away and another pump on the hot port pumping into the valve both wired to run at the same time .They had also installed the pumps for the hi temp pumping into the return while all the rest of the pumps are on the supplies and it seems when the radiant zones anre running the hi temps get no circulation until you shut off the radiant .All the piping is 1 inch and looks like a fool with no idea did  it even though these where supposly pro .I kinda feel that maybe the radiant can be used for floor warming but it will not heat the place when the femps drop to about 20  and we are planning to just load the place with either baseboard or panel rads.It seems from a couple of heat loses program sceanairos that the slab could be soaking away up to about 50mbtu to the earth what a waste. Am i on the right track or is there any better thoughts on this job it very sad that installer do not follow instruction nor take the time to install sysytems properly and of couse they have no answers or do they return  calls but they did i get paid and cash that check.What a sad state of afairs .Peace and good luck clammy 

circ on boiler on constant 180

@ January 29, 2012 10:55 AM in Ideas on indoor temp control opions

yeah ,the tekmar outdoor reset would curb some waste and as for the indoor sensor it would be hard to find one spot to locate it being some areas are radiant with baseboard and it;s stat and zone valve still in place. The  1 st floor is pretty open except for a few bedrooms and mid floor music rooms strange floor plan with alot of custom  details like floating rooms   .I fiqured by putting  2 or 3 wireless t stat or better yet wireless remore sensors to a temperturing averaging thermostat i could use that to cycle the boiler and the tekmar to control temperture .I would really like to do some thing with the pump also like resize it to the proper sized pump and use a wet rotor but the way it is piped there is a consideable amount of head needed due to the system design and the 30 or so mono flow tees and zone valves it must over come .The way the mechincals are i could spend at least 3 weeks to straighten it out ,they need a total re do of there mechincals including a pool heater doing a outdoor jacuzzci 175mbtu ,2  100 gallon hot water heater  a crown 320 mbtu all tied into a 8 x8 chimmey  and all tied (hacked)into the chimmey with a single  8 flue pipe.Also the burmham 100mbtu direct vent boiler doing the  radiant and vented with 1  2 ft piece of stainless safety vent and the other 12 ft done  in standard galv flue pipe.The burmham doing the radiant cycles so often it is just way to funny like every 8 to 12 minutes even funnier is the 2 old one siting in the corner dead from flue gas condensation the same fate the new one shall face being the way it is piped .Could make a good buck there and install a system which would drasticlly reduce gas comsumpition and increase comfort   except like many super wealthy they will pass this hog pog of nothing onto the next owner in lieu of spending and improving there investiment and reducing comfort and realibity of there system .The ulitimate bull is having to go through this home room to room to bleed the baseboard with a bucket and a hose with custom wood work and carpets   what ajack ass set up and potental promblem first time the wall panels get muddy water on them .A side note is the boiler water lookes like chocalet milk yet worse .Again sorry for the rant peace and good luck clammy

Ideas on indoor temp control opions

@ January 29, 2012 9:28 AM in Ideas on indoor temp control opions

Well the set up goes like this .9000 sq ft home ,all baseboard with each room having a thermostat and a taco zone valve with a purge valve under the baseboard cover(haydon baseboard nothing speical and excellent to bleed) There are no end switch tie in to the boiler.The system piping is a 2 inch supply with mono flow  tees it is not a single loop there are 2  1 1/2  and 1  11/4 returns .There is a single 3/4 hp b&g series 60 pump .The boiler and pump run off a honeywell outdoor sensor which turns it on at 70 degrees and the whole shebang runs balls out till it is over 70 and then shes off,cool set up .Being the whole basement is finished aside from the boiler room area.I was thinking of installing some wireless remote thermostats and have them cycle the boiler instead of running straight out .Running wires off the existing remote zone valves would be a huge PIA and a mess.The boiler is piped straight through and could use a major piping up grade like a outdoor reset /primary secondary piping  and possiblable another boiler and staging controls.It is totally amazing this is in a very hi end developement  and these home go for about 10 mil and up  the workmanship was a train wreak i could not believe the mechincal room .I know the guys gas bill must be about 1500 bucks a month in mild weather and the boiler room is  a sauna.Sorry for the rant but whats the thoughts on wireless stats for my purpose .Peace and good luck clammy  

Ideas on indoor temp control opions

@ January 29, 2012 9:28 AM in Ideas on indoor temp control opions

Well the set up goes like this .9000 sq ft home ,all baseboard with each room having a thermostat and a taco zone valve with a purge valve under the baseboard cover(haydon baseboard nothing speical and excellent to bleed) There are no end switch tie in to the boiler.The system piping is a 2 inch supply with mono flow  tees it is not a single loop there are 2  1 1/2  and 1  11/4 returns .There is a single 3/4 hp b&g series 60 pump .The boiler and pump run off a honeywell outdoor sensor which turns it on at 70 degrees and the whole shebang runs balls out till it is over 70 and then shes off,cool set up .Being the whole basement is finished aside from the boiler room area.I was thinking of installing some wireless remote thermostats and have them cycle the boiler instead of running straight out .Running wires off the existing remote zone valves would be a huge PIA and a mess.The boiler is piped straight through and could use a major piping up grade like a outdoor reset /primary secondary piping  and possiblable another boiler and staging controls.It is totally amazing this is in a very hi end developement  and these home go for about 10 mil and up  the workmanship was a train wreak i could not believe the mechincal room .I know the guys gas bill must be about 1500 bucks a month in mild weather and the boiler room is  a sauna.Sorry for the rant but whats the thoughts on wireless stats for my purpose .Peace and good luck clammy  

sorry non condensimg

@ January 15, 2012 12:35 PM in looking for a replacement direct vent boilers

Sorry this is a application  for a non condensing unit There are no trapped fixtures;laundry rooms etc any where in the area to get rid of the condensate  and cutting into a stack 40 feet away and cutting a y in and the  required  trap primer and such is out of the question and all would have to go through  the condo association   .The other reason being this is a hi temp system where they did not install enough baseboard in a lot of areas and all those areas are non accessibility's i doubt it would be in the condensing mode even early in the season to justify it .If i where to do a mod con it would probably be a peerless pure fire being i have a more reliable source in case of service issues as for triangle tube i have installed a few and they are nice  but the supplier that sells them in my area or i would get it from  does not stock parts which to me is a issue i mean any body can sell any thing but if you don't stock any parts what good is it for the guy installing and servicing them and what about the customer .Peace and good luck clammy

looking for a replacement direct vent boilers

@ January 15, 2012 7:47 AM in looking for a replacement direct vent boilers

Again looking  at a job to replace a 30 year old hydrotherm wall hung celtic promblem being my local supply house which had carried and stocked parts  has dropped baxi completly and have also returned all service parts in stock.There are a few larger supply houses around which will get them and embassy wall hungs also  but do not stock squat and from past experences have always dropped the ball when it comes to just about everything so i usually do not deal with them knowing that they stock no service parts for any wall hung or condensing boilers that they sell and the local rep truely sucks ,I was thinking about using a peerless PSC2 seal combustion boiler but am worried about power vent noise being the first floor tenant is ranting about the noise from the existing celtic .On another note the water chemestery is awful super hard and the original piping is terrible 2 zones with one 3/4 feed unit is a 2nd /3rd floor unit heat lose about 55mbtu .If any one has used the peerless psc2 did you think it was quite as say compared to a slantfin direct vent which in my book is as load as a bolt in a hub cap .peace and good luck clammy

NX all the way

@ January 4, 2012 5:02 PM in Buderus

I also have put a few g115 w nx burner and have had no issue with that set up .I would also have your chimmney checked out a liner kit may be in order being they do run a low stack temp and i personally would rather get a good stainless liner installed rather then try to raise the stack temp it kinda defeats the purpose of the boiler eff.Great 3 pass boiler and do yourself a favore and install a tiger loop on the burner.This is the normal set up that you would see in germany .I use one on all my buderus oil fired boiler with the higher pump pressure and smaller noz it makes good sense also use a regular general filter and also a spin on gerber small nozzles and hi pump pressure can clog a small noz very easy ,hope this helps peace and good luck clammy

re pipe / vaporstat

@ December 29, 2011 10:38 AM in fixing a webster type r vapor system

From the looks of that header it should be repiped and that system should be operating at less then 1 lb of pressure .For starters i would have a vaporstat installed and lower the operating pressure to ounces instead of pounds and  see how she runs i would also look for non working traps and non working cross over traps and water seals on the ends of the mains and dry return drips which should be  vented seperatly and tie together well below the water level of the boiler giving you a good seal and perventing steam from reaching through to the dry returns  .I would also check your systems air vents on the dry returns to make sure they are working if not replace them .It is kinda funny that guys still replace steam boilers and forget all the details and then add extra expense to the HO.I usually check all these things and include them in my propasal and let the HO know excatly what has to be done for there system to operate properly .This of course cost more money up front but usually always pays off in comfort and fuel usuage and it usually always is cheaper then guessing and more bills from the contractor because it was not including .Do yourself a favor and become a educated comsumer and get some of dans book including the lost art of steam heating and you will be able to realize weather your contractor knows what he is doing or weather he is just giving you the bussiness and learning at your expense .Personally i always tell the truth about what i see and the action to take to correct it .It is always easier to remenber the truth over lies so i alway tell it like it is that way i do not have to remenber a lie .PS i don't like candy coating it neither .Peace and good luck clammy  .On a closing note if they did not get it right the first time i highly doubt they will get it right the second or thrid time either but they will make the bill out correctly thats for sure in my experence. 

air flow / velocity meter

@ December 29, 2011 9:51 AM in air flow / velocity meter

wondering whats the general thoughts on them .I have a supco unit which i have used to check my unico installs and it seems fairly accurate .I have been asked to test a and balance a 100 % make up air system .we had nothing to do with the install besides order the unit from what they specified .I am wondering will this supco DAVM+ will be acceptable or weather we should fork up over a grand for a better unit which will be used once .These reading are being ordered by the mech engeeners for them to get a CO .Again we had nothing to do with any thing on the install ,duct sizing or cooling sizing .We already kinda know that it will be screaming due to the duct sizing but we are only to get the readings and balance it out there are also no dampers any where and this was a union tin job wrapped with bubble wrap .Any input to as weather this meter will be accaptable would be great.Peace and good luck  clammy

water seal

@ December 15, 2011 12:19 PM in Two pipe question

Sounds like this sytem either at one time had a wet return which the steam main dripped into or a u bend water seal at the end of the main which dropped down and looped back up into and  then tied into the dry retun .I have ran into and seen this piping orangement  .If it is a 2 pipe system those 2 x 3/4 tees most likly had cross over trap instead of air vents but i have seen it both ways  .If you build a water seal please install a vapor stat other wise you will push the water out of the seal unless you make your loop over 30 inches mimiun and remenber to fill the seal loop prior to starting the boiler other wise steam will get into that dry return ,If you install a f and t at the end of the main make sure you do not have any steam pressure in the dry return other wise it might start stacking up condensate and other issues will arise.Other thing to take alook at is does each dry return tie together above or below the water line .I always seperate them add a tee for  air vents and drop them seperatly into a wet return .Even though in some older system it would have tied into a single main air elimator but these system where usually originally coal fired and fired for many hours unlike modern day equiptment which is electronically controlled by thermostats and pressuretrolls.Dans lost art has all this stuff in it if you don't own a copy or two get one well worth the price a hunderd times over peace and good luck clammy

max velocity

@ December 12, 2011 3:22 PM in Max velocity

Dan does have the formula in the lost art ,I usually always try to get it down to below 12 fps and have never had a issue with any boiler that i have installed usually peerless.weil.utica and a few others.You will find that usually when wanting to obtain lower exiting velocities below 12fps you will be using both tapping and have a miniun of a 3 inch header this is a usually for below about 150 mbtu over that it's usually 3 inch risers into a 4 inch header.Also alot depends on how many risers you are conecting to the header over 2 risers connected to the header then think of up sizing like 3 to 4.The slower the exiting velocty the dryer the steam .I in the past have also posted question concerning this subject and did not get much reaction .So i myself started doing the math and came to my own conculsions and use that approach when i install steam boilesr and never have issues with carry over steam or wet steam or issues realted to improper near boiler piping.This of course always increases the price of the job and usually puts my price higher then others but it is cheaper to do it once then doing itthe second time  for free or to have the HO just live with it which is what alot do cause the contractors says thats the way steam operates .As always the best place to start when installing a new steam boiler is to take a look at the manafactures installation and operation instructions and there requirements for the near boiler piping and always remenber that there piping dimensionsare the minuin and when it comes to residental low pressure steam heating systems bigger near boiler piping is better  Peace and good luck clammy   

A few more tib bits

@ December 2, 2011 3:52 PM in Opinions of dianoges

This HO contact our host many many  years ago and was finally given some ones number ,who had came out and did some repairs that really needed to be done and she was not happy with it a few hours later.What i think i may do is just give her a number to a insulation company and have them insulate it and then give her a list of repairs to be done and she can get who ever to do it but not me .And gordo thanks for your insight i also am a gut feeling guy plus a buddy did work there and got stiffed the HO stated he was the best plumber that she ever had in her home but he would not return her calls .I asked him about her and he  barely remenber the job but it came back to him ,it seems i forget his rule which is if you stiff me i don'tpick up your calls nor does he return them.but  as i say like a small fish that to small to keep i toss them back to the sea and let them deal with some quick talking and  more knuckleheading  just what they deserve .Thanks  peace and good luck clammy

ombustion anz

@ December 2, 2011 3:34 PM in combustion analysis

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

Opinions of dianoges

@ December 1, 2011 7:19 AM in Opinions of dianoges

Recently looked at a steam system ,2 pipe what was a webster but the return trap was removed and a menorah of gortons where installed and most of the cross over traps where replaed except for a hidden one that was by pass and was hidden .The HO is unhappy with the systems performace of 2 large rads which are located in a sun porch .Of course these rads are on the longer of the mains  and do heat up after a good long cyle but HO is not happy.Aside from the 1 bad crossover trap none of the mains nor the dry returns or near boiler piping is insulated.The boiler is piped in dwv copper fittings  and no where near proper and the main take offs are 2.5 but only tied in from the boiler with 2 copper.Alot of knuckle heading has gone on including 2 recessed rads repiped in 1/2 copper with no traps and plently of raditor valves have been changed from orifice type to standard rad valves .Ho stated last year some 1 hour service co came and had  add to a stop leak to the system because the boiler was leaking steam .The HO seems to think that they will sell the home with this boiler still there in 5 years or so .She has also stated that 2 pros have come and done work on her system but she  was not happy with there results after they left because the rads did not heat to her likens .Aside from the mis piping ,bad crossover trap ,no insulation my one issue is that there is no loop seal on where the 2 dry returns are there tie togetherand drop as a single pipe instead of dropping below the watre line and then tieing together am i just being anal or am i right in my thoughts .Do any think that the HO may be asking to much from her system for what she wants to pay stating each contractor charges to much and each ripped her off she has stated she has been through at least 50 plumbers .I susrly know what the system needs except i do not want to get stuck with a no pay or a HO that excepts mircales from a few hours work on a system that has been knuckle headed for years .Also the original boiler watre line was about 43 inches the 25 year old peerless is about 24 alot of the old wet return is a bit above the boilers water line very funny stuff .What the feeling about balancing it out of heating the sun room .Peace and good luck clammy PS i was referred by a local supply house who she tryed to get there boiler steam guru guy there .

2 schools of thought

@ November 28, 2011 6:27 PM in Beckett AFG Oil Burner Issues

I personally like a standard general filter at least when you change the filter you get an idea of how much junk your filtering and the condition of your tank .While the spin on type do a great job and changing them is usually alot cleaner of a job because there is less of a chance of spillage but when a general is set up right it is no big deal .Also do yourself a favor and get a set of 3 flexable oil lines and some 1/4 fittings ,nipples ,coupling and 90 's it makes connections to the pump easy also install a tee with a plug in the supply line to the tiger loop this way if there is a issue you an throw a vacume gauge on it to see what your pulling .This was the way i used to do it when i worked the oil game 24/7 service and i like to solve the issue not just get you flame hate the call back and the ball busting when ya have one and every one has a call back once in a while .Thats how you learn but it should not be at the custermers expensine unless ther are other issues .As for filter at the tank or by the equiptment i take the filter by the equiptment .Hope this helped .peace and good luck clammy

tiger loop

@ November 28, 2011 7:13 AM in Beckett AFG Oil Burner Issues

Do yourself a favor ,replace the pump /solonoid and have a tiger loop installed .When ever i install any oil fired equiptment i install a tiger loop if the oil lines are set up as a 2 pipe .Look at most german oil fired equiptment and they usually always recommend a tiger loop .I always use them on any burner thats oil pump pressure is being boosted above 140 psi .A tiger loop will deairate the oil and cut pump vacume and in some cases hi vacume can cause nunance lock outs .The big issue i have with standard 2 pipe is you filter all the oil you pump in your case 18 gph and burn what 1 gallon per hour .Take a close look at  the peerless instruction it may even show a tiger loop in there oil piping diagrams ..high vacume in oil piping always causes issues .Peace and good luck clammy

Another note

@ November 26, 2011 4:33 PM in prestige lp issues what would JC do

I am familar with  mod cons but have only installed 2 other prestigesand did not have the manual with me when i went and looked at teh job  i mostly did HTPs and peerless and a few baxis .With out i and o manual i was unable to go througt the  installers parameters.The HO has stated that he was told the the unit does not require to be cleaned or need yearly maintance and has said that he has had issues from the start.peace and good luck clammy

prestige lp issues what would JC do

@ November 26, 2011 4:26 PM in prestige lp issues what would JC do

Just wondering what others would do .Was called to look at a prestige 250 that was installed about 3 or 4 years ago has some noise issues when running it was a barter job and i did not do it nor had any thing to do with it .Well to start off the piping was not up to snuff in my book reduced at the boiler from 1 1/4 to 1 inch and sort of ps piped but way short of the mark aside from only a 3/4 gas line and the LP  regulator about 8 ft away the inlet pressure was 11 w c and drop to about 9.5 when running .I really could not get a combustion reading due to the fact that the boiler would not run long enough 1 or 2 minutes and it would cyle off .It started off and ran fine with the outdoor reset wired in .I disconneted the sensor so it would run longer but it did not help and the burner then started to backfire upon start up .I re conneted the out door sensor and the start up rummbling stopped .I still did not get a combustion reading off of it .The boiler was piped as the primary loop  with the seondary being the system except the installer did not follow proper P/S distanes on the tees and jammed a st ell into the return tee of the secondary loop so the flow into and through the secondary loop is crap with a huge temperture drop .The HO has asked what i could do i suggested to repipe it corret the gas piping and flue piping which also a far from the manafactures specs but when all is done the boiler is still way over sized .The home is about 2400 sq ft with about 130 ft of slant fin 30 .Am i way off base in thinking of tossing this boiler and just put in a properly sized cast iron direct vent boiler.I already know that the baseboard was not over sized so in my book it would only be early and late season where it might condense and maybe te modulation might help but i feel it ain't gonna justify the cost .Last year he burner 1800 gallons of LP .He has had the installer and the  local rep they all say it is normal and its running fine i say it is BS at close to 90 btu sq ft they are cta.Also upon first starting there is alot of noise like boiler water is boiling and the boiler very quickly ramps down then a minute later the burner cyles off .The guy installed a taco 0010 as the boiler pump and of course the installation and operation books where not there .Thanks for any input peace and good luck clammy

prestige lp issues what would JC do

@ November 26, 2011 4:26 PM in prestige lp issues what would JC do

Just wondering what others would do .Was called to look at a prestige 250 that was installed about 3 or 4 years ago has some noise issues when running it was a barter job and i did not do it nor had any thing to do with it .Well to start off the piping was not up to snuff in my book reduced at the boiler from 1 1/4 to 1 inch and sort of ps piped but way short of the mark aside from only a 3/4 gas line and the LP  regulator about 8 ft away the inlet pressure was 11 w c and drop to about 9.5 when running .I really could not get a combustion reading due to the fact that the boiler would not run long enough 1 or 2 minutes and it would cyle off .It started off and ran fine with the outdoor reset wired in .I disconneted the sensor so it would run longer but it did not help and the burner then started to backfire upon start up .I re conneted the out door sensor and the start up rummbling stopped .I still did not get a combustion reading off of it .The boiler was piped as the primary loop  with the seondary being the system except the installer did not follow proper P/S distanes on the tees and jammed a st ell into the return tee of the secondary loop so the flow into and through the secondary loop is crap with a huge temperture drop .The HO has asked what i could do i suggested to repipe it corret the gas piping and flue piping which also a far from the manafactures specs but when all is done the boiler is still way over sized .The home is about 2400 sq ft with about 130 ft of slant fin 30 .Am i way off base in thinking of tossing this boiler and just put in a properly sized cast iron direct vent boiler.I already know that the baseboard was not over sized so in my book it would only be early and late season where it might condense and maybe te modulation might help but i feel it ain't gonna justify the cost .Last year he burner 1800 gallons of LP .He has had the installer and the  local rep they all say it is normal and its running fine i say it is BS at close to 90 btu sq ft they are cta.Also upon first starting there is alot of noise like boiler water is boiling and the boiler very quickly ramps down then a minute later the burner cyles off .The guy installed a taco 0010 as the boiler pump and of course the installation and operation books where not there .Thanks for any input peace and good luck clammy

Reply to alfred e

@ November 15, 2011 10:25 PM in New Boiler going in!

Usually when piping the return tapping iuse the full size nipple say peerless 63 series 2 1/2  tapping .I do not reduce my return tapping and i usually do not drop my vertically ,i would go horizontally  to line up with my equilizer.I would use say a 2.5 x 2 tee the 2 inch for my equilizer ,One of the reasons i do this is to be able to wash out the bottom of the boiler i have some custom made wands for the job i like to wash out the bottom end between the sections after a few years of operation.This is just the way i do it to each there own peace and good luck clammy 

1 comment

@ November 13, 2011 11:41 AM in New Boiler going in!

Instead of a elbow on the return into the boiler you should put a full tee with a reducing bushing and then a full port ball valve and a adapter to a hose bib .this way you an drain the boiler quickly and flush out the bottom on the boiler  tomake it easy to remove any sediment.On another note how close is the wate line on the new boiler compared to either the one your replacing or the original .Make sure any main drips if you have them did not lose there water seals and also install a vaporstat ,trane systems where vapor systems and work best when using a vaporstat instead of pressuretrol that comes with the boiler  and make sure your main vents are sized properly and working  and if you have  cross over traps make sure they are working properly to .peace and good luck clammy

Check for water seal

@ November 10, 2011 9:05 AM in Vapor Vacumm system flooding

Check your boiler water line against where your drips and wet returns tie together ,make sure you have a water seal or that all these connection are well below the boilers water line .if they are not then this may be the issue ,i have ran into this a few times it is mostly due to a differene in boilers water level from the original boilers water line to the newer boiler.Usually the way to corret it is to fiqure the original water line and build a false water line to cover all those formerly wet returns and drips . Remove check valves from the returns and install a hartford loop make sure that your equilizer is properly sized and that the return lines are not  clogged.Last but least make sure your near boiler piping exceeds the manafactures specs most vapor systems perform best when the steam is dry .Hope this helps peace and good luck clammy