Steam boiler equalizer

ordellrobbie · October 29

Burnham keeps saying that on their residential steam boilers that the equalizer needs to be smaller than the header. I have never heard of this until they started saying it. I think the first time I heard about it was maybe five years ago. I have been installing steam boilers the same way for the past 25 years, which is on a 2 inch header, I will drop down to the equalizer and keep it 2 inch. On boilers with 2 risers and 3” header I will drop down and reduce to 2”. They explained why it needs to be reduced and I don’t even remember and didn’t even understand the explanation that they gave. Something to do with pressures. My thought is that the bigger the equalizer is the easier it is drain the water. We continue to do it this way even after they say that it needs to be reduced and we never have any issues. I’m just wondering how they came up with this all of a sudden or have I been missing it all these years and does it really make a difference? Thanks

ethicalpaul · October 29

No, there's no reason it needs to be reduced.

And there's no need to not reduce it. Yes, you see no issues by not reducing it just like you'd see no issues by enlarging it to 6" pipe. But that doesn't mean it's doing anything.

If the water quality is where it should be (clean with no oil) the equalizer won't see hardly more than a couple tablespoons of water ever.

I don't know specifically what's on Burnham's mind, but every boiler installation manual from every manufacturer has it reduced. Now that I've said that, someone will post an installation manual proving me wrong.

But here's Peerless:

Jamie Hall · October 29

Is there a Burnham rep. on The Wall? I'd love to hear their logic on that…

An equalizer does serve a couple of useful functions, but none of them involve gas flow although it can, in some installations, carry a fair amount of condensate. So as long as the diameter is big enough to handle the condensate flow, it will be big enough.

ordellrobbie · October 29

All the manuals that I’ve seen have the equalizer as a minimum size. It doesn’t say that it can’t be bigger. Burnham was the same up until recently as far as I can remember. We always run 2 inch because it’s easier to not switch sizes for such a small amount of pipe.

ChrisJ · October 29

https://forum.heatinghelp.com/discussion/comment/1869890#Comment_1869890

All I see in their Independence manual is 1 1/2" minimum, no comments on a maximum equalizer size?

dandub1960 · October 29

Reviewing my copy of LASH recently i see the admonition to never go below 1 1/2 inch. Based on old-timer experience more than anything else. Dan seems to like big ... equalizers.

Jamie Hall · October 29

https://forum.heatinghelp.com/discussion/comment/1869914#Comment_1869914

The idea being to ensure free drainage of condensate and any initial carryover from the header…

EBEBRATT-Ed · October 29

The way you are doing it is fine. The equalizer has pressure on both ends so there is little flo. Steam can't move through it as the bottom is trapped by water. The only flow is condensate from the header and supply pipe………unless the boiler is throwing massive amounts of water up……then you have other issues.

I agree with your method switching pipe sizes for a few feet of pipe is a waste of time and money.

ethicalpaul · October 29

https://forum.heatinghelp.com/discussion/comment/1869917#Comment_1869917

You sure don't need 1-1/2" pipes to carry that tiny amount of water.

So you guys would rather run a 2-12" or 3" header all the way down to the Hartford loop? Suit yourselves, but I sure liked cutting, threading, and fitting smaller pipes rather than larger ones in my admittedly limited experience.

dandub1960 · October 29

https://forum.heatinghelp.com/discussion/comment/1869917#Comment_1869917

While there is no net gas flow in the equalizer obviously, I wonder if the bigger pipe is better at damping out water level oscillations which would create pressure oscillations in that connection. Serve as a big mushy spring instead a skinny hard one? Makes me want a 2 inch equalizer on my new boiler instead of the 1 1/2 Peerless shows in their piping diagram.

mattmia2 · October 29

If the pipe is smaller the surface of the water at the hartford loop is smaller if steam finds its way down there but that can really only happen on 2 pipe systems.

ethicalpaul · October 29

https://forum.heatinghelp.com/discussion/comment/1869946#Comment_1869946

no, a bigger pipe will not dampen water level oscillations in the boiler

Jamie Hall · October 29

From the standpoint of pressure equalization, a quarter inch tube would work just fine. But… consider plubming drains. Maybe there isn't all that much carry over or condensate in the header, but… maybe there is, and you want it to drain. I'd want at least inch and a half…

ethicalpaul · October 29

sorry to bring this up but surely you remember when I showed that a closed valve does the same job of pressure equalization as a pipe does 🙂

A quarter inch isn’t necessary.

For the drain feature, each manufacturer publishes its requirement. Pipe what lets you sleep at night I guess!

EBEBRATT-Ed · October 29

@ethicalpaul

The op was saying (I think) if he has 2" risers and a 2" header, he might do the equalizer in 2" even if 1 1/2" is large enough. Same thing with 2" risers and a 3" header.

You pretty much have to buy pipe in at least 10' pieces. You don't want to buy 3" 2" and 1 1/2" plus lug all the different size fittings, different dies etc.

He was just saying keep it 2" to make things simple and I agree with that. It would also depend on how many boiler you install. A HO may do it the simple way keep it all one size. Someone in business who can use up the extra pipe and fittings would probably do different.

Burnham saying the equalizer needs to be reduced??????……..you know what I think of Burnham. Any mfg that dose that just shows how dumb they are

Jamie Hall · October 29

There is one situation in which pressure equalization is helpful — if not mandatory. It is in the functioning of the Hartford (or Gifford) loop. Not to equalize the pressure on the two sides, no. What it does, though, is in the event of a wet return leak is to act as a vacuum breaker. If the equalizer weren't there the Hartford Loop would be a siphon, and would quite happily drain the boiler down to the boiler inlet fitting, rather than stopping the loss at the elevation of the loop.

ordellrobbie · October 30

Smaller boilers I use single 2” riser, 2” header, and 2” equalizer. Anything that requires 2 risers and 3” or 4” header I would use the minimum size required (usually 2”). It’s faster. The difference between 1 1/2 to 2” is insignificant to me in cost vs time savings. 2” to 2 1/2 , 3”, or 4” on the other hand is significant and takes longer to cut and thread than 2” which is why I don’t pipe those full size. My question was whether there is any upside to reducing the equalizer on the smaller boilers or down side to keeping it full size other than cost of 1 1/2 vs 2” which is insignificant in my opinion for a couple fittings and nipples and maybe 2’ of pipe.

EBEBRATT-Ed · October 30

@ordellrobbie I think wat your doing is fine. I think Burnham is off base.

ethicalpaul · October 30

https://forum.heatinghelp.com/discussion/comment/1869990#Comment_1869990

The loss doesn't stop there…the rest boils out as steam, then the LWCO does its job.

@ordellrobbie again, there is no reason to reduce it if you don't want to.

Do you have a reference of where Burnham said you must reduce it?

Jamie Hall · October 30

True enough on the LWO — but it should be noted that the primary (auto reset) LWCO shouldn't be much below the Hartford Lopp level…

ordellrobbie · October 30

https://forum.heatinghelp.com/discussion/comment/1870013#Comment_1870013

They’ve said it in their steam classes and more recently we had to have a rep come out fir an issue with a boiler and he told us that we did a really nice job piping the boiler but the one thing that was wrong was the equalizer needs to be reduced in size. I have heard it several times over the past 3 or 4 years.

ethicalpaul · October 30

well they are just making stuff up 😂

Did you ask them why they still offer the clearly deficient IN series? That’s what I’d like to ask them

STEAM DOCTOR · October 30

https://forum.heatinghelp.com/discussion/comment/1870055#Comment_1870055

I have not read the entire thread, so this may have been mentioned before. Only thing that I can think of is that they're worried about steam bubbles going up The equalizer, and entering the header from the back end. By reducing the size of the equalizer, they are creating a pressure differential which will allow the front end of The header to overpower the steam coming up to the back end.

ethicalpaul · October 30

How would steam bubbles rise from the water in the equalizer/hartford loop area?

How would a reduction in pipe size create a pressure differential in a pipe when there is no flow of air or steam? Recall that the pressure is equal at both ends of the equalizer (even if the equalizer has a closed valve in the middle)

EBEBRATT-Ed · October 30

The whole thing sounds like BS to me. Will have to download a Burnham manual (yuk) and read it.

ChrisJ · October 30

https://forum.heatinghelp.com/discussion/comment/1870152#Comment_1870152

Similar to demonstrating a boiler by letting it build pressure and then dumping the supply valve wide open so it produces excessive carryover and telling everyone it's what is really going on inside the pipes?

The difference there is, I guess that was to kind of exaggerate the problem and get people to actually pipe them correctly. But still.

ethicalpaul · October 30

Everything in their manual says "Minimum"

If I had to really guess, I'd almost say they are misstating the rule that IF an equalizer pipe is reduced from the size of the header, then the reducer MUST be a reducing elbow, or MUST be a reducing bushing on the vertical pipe and SHALL NOT be a reducer on the horizontal header.

But really can you blame them? So many licensed plumbers/HVAC installers are completely clueless about steam, doesn't it follow that even some steam boiler manufacturer's actual employees might have a few wrong ideas too?

ethicalpaul · October 30

https://forum.heatinghelp.com/discussion/comment/1870153#Comment_1870153

I've grown to hate that video because it has become clear that many people who watched it think that's how boiler near boiling piping behaves all the time.