New Steam Boiler Installed, Water Hammer, Prematurely Turns Off, Frustrated

What Ed says above. And I'll bet there's still lots of cleaning and skimming that has to be done to that boiler and piping.

The purpose of the right angle swing joints circled above in red by 109A_5 is to allow expansion and contraction of the boiler. If bridled by a header without the ability to expand and contract, the sections can pry apart, causing leaks and premature boiler failure.

This is why the manufacturer recommends swing joints on the header.

One other item on the piping — which looks minor but may not be. The steam takeoff to the mains exits from the side, not the top, of the header. Nope. That is almost guaranteed to get water up into the steam mains which will cause water hammer — even if all else is good.

The temperature difference with the thermostat is a bit odd. If you app is still showing a call for heat, you need to find out what is causing the boiler to shut off. Something is…

is there a skim port on the other side or are they removing the plug to skim?

There are no header offsets, swing joints or expansion joints shown in the photo of the boiler piping.

Is there a vent on top of this pipe ?

the pressure needed for it to heat is venting. pressure can cause hammer in some system designs but from what i can see of yours I don't think you have those things going on but there could be things i can't see.

the building of pressure could be venting or that the boiler is too big. you won't know until you measure the size and type of the radiators and figure the area of equivalent direct radiation in the system and compare it to the output of the boiler.

the hammer is probably boiler water quality or pitch that got changed with the new boiler install. that pipe to the main on the right needs to slope toward the header or it will hold condensate and hammer.

the boiler needs swing joints as mentioned to protect it from the expansion of the piping with temp.

Steam boilers should be sized to match their load, the radiators. The contractor should have measured all the radiators, calculated the total EDR (Equivalent Direct Radiation). Then sized the new boiler by picking the boiler that best matches the total system EDR to the boiler's Square Foot rating. Oversized boilers typically build unneeded pressure and cost more, neither helps you.

They probably should have inspected the whole system for any deficiencies like poor main venting. With poor main venting it takes longer to fill the steam mains than it needs to. So you may be burning fuel fighting a restriction that does not need to be there. Also filling the mains as fast as possible helps more evenly heat the structure.

When they were done with your system, if it worked better than it did with the old boiler you would probably be happy. Instead you are not happy and for good reason.

Poor piping practices that equalizer piping is something to behold . Zero swing joints ,sorry to say there ain't nothing there that someone some experience installing steam boiler would have done in such a manner. The side take off main is not helping a thing . Being you have 2 dry returns they should have been separated and each had a main vent added ad then dropped into the wet return . The lack of swing joints as other have said is a real deal breaker being anyone who has read the instructions and has any mech aptitude surely should no better. Over time it shall surely shorten the boilers block and stress it out .

You have a two pipe system so each and every trap should be check to ensure they are working properly ,i believe that any steam system that is 2 pipe when the boiler is being replaced that the customer should be advised that there traps may need new elements or new traps being nothing last forever and this way you aint doing them for free.

From the looks of the piping they did not a vast amount of experience or knowledge on proper steam piping nor following instruction . I guess now they should come back and install properly and do everything that a real steam installer would do like figure the edr of the radiators before just putting the same as was there and hoping the last guy was right ,not the smartest practice or one i would dare practice.

I really hate to say but i have rarely seen hvac companies do steam correctly maybe a few instances but at large i wish they would stick to the tin and leave the steel piping to those who have experience and knowledge being not every job is easy and brings money to the bank at least not when there issues and return visits . These type of mis piped job never happen w those who know exactly what they are doing and usually never by owner /operator 1 man companies being we cannot make mistakes at least not on something like piping a steam boiler correctly it truly is not hard not a giant brain required . This happens when there's only braves and no chiefs and by those who are more about $ then really doing top end quality work and as seen they cannot have to much steam smarts being there plenty of low hanging fruit that either they where un knowelable of but still got the job and did not do correctly .

If it was price shopping well you may have gotten a bargain but your left w a steam system which does not operate correctly and unless they come back and correct you have pooh and most likely have to find some one else to correct . I would not release a final payment for sure .

peace and good luck clammy

These installers need more schooling.

They don't need to know how to install a steam boiler they are not even at that stage yet.

They need to learn how to read

Oh, this is 2 pipe. I thought it was 1 pipe from the boiler piping.

The vent(s) on the returns and the traps on the radiators need to both be working for the air to vent and the radiators to heat properly. In addition to either the traps or the vents being failed closed, traps failed open can let steam in to the returns and keep other radiators from heating by either closing the vent on the return or heating traps from the return and causing them to close. There should be no steam in the returns.

33% is more pickup factor than most systems have. the piping in most systems is more like 10% or less. the edr(ibr net square ft or something like that) number on the boiler ratings plate already has 33% subtracted so the output of the boiler is 33% more than the square foot rating. if your calculations are correct the boiler might be slightly undersized for the connected radiation but it is very close. with 2 pipe steam that really isn't a problem if the system is working properly.

A crossover trap connects a steam main to its corresponding dry return, and allows air from the main to get into the dry return. The air in the dry return is vented at or very near the boiler, so a crossover trap functions as a main vent — a very large one, in fact. Proved of course that the dry returns are vented — which they must be anyway.

Condensate from the steam main is handled in one of three ways. If it is a counterflow main, it trickles back to the boiler. Rarely it is handled by a water seal (a loop of pipe from the main to the floor, and then back up to the dry return). Most commonly there is also a wet return associated with the mains, and it just drips into that.

I suspect the dry return keeps going away from the camera's point of view beyond the point of the crossover trap and parallels the steam main around that part of the structure, providing a return for those radiators. More pictures of the piping and the main vent would help us understand your system better.

If the old boiler (before it failed) basically heated the building sufficiently, the new one of the same size should work relatively the same. However if it (the new boiler) is surging or other dysfunction because of poor piping and water quality and needs further attention the steam may not be getting to the radiators properly. If the steam can't get to the radiators properly they can't dissipate the heat properly and the pressure will rise.

If the venting is inadequate and the steam can't properly push the air out of the system so the steam can get to the radiators to dissipate its heat into the living space the pressure will rise.

I suspect there is multiple issues going on here. The new boiler install just kind of aggravated things to the point that you noticed.

@superdave17

Make it easy on yourself no need to go through the calculations.

Just add up the EDR for all the radiation. When you get that right. Compare it to your boiler rating in Sq feet of steam. Your boiler is rated for 571 square feet. That already includes the PU factor. No need to convert to BTUs and back and forth its just more confusion.

EDR=Sq feet of steam