The "equalizer" is mis-named. It does nothing to equalize anything.

hot_rod

https://forum.heatinghelp.com/discussion/comment/1743629#Comment_1743629

it is a centrifugal circulator pump, although aka booster in earlyB&G speak

ethicalpaul

He's trying to make a joke at my expense, @hot_rod I guess because I dared to say the Equalizer is mis-named?

ChrisJ

Some do not like things being questioned.

PMJ

https://forum.heatinghelp.com/discussion/comment/1743651#Comment_1743651

True experts never mind questions. In fact true experts welcome them from any source honestly seeking better understanding.

I think the disconnect here is contractors experiencing these questions as a judgement that some of us think that they should be doing something different. They should not think that. It should be well understood by all that contractors have no choice but to install equipment to existing specifications, whatever they are. There is no business reason to question the specs or investigate the theory behind them. They receive no income for science projects. Timely, efficient execution of installation and repair based on specifications proven over time to work is logically the complete focus of their efforts, and rightly so.

ethicalpaul

Thanks PMJ. I agree, I am not judging any installation choices in this exercise. I would still pipe this drip, it has good reasons to exist.

PMJ

https://forum.heatinghelp.com/discussion/comment/1743665#Comment_1743665

It seemed clear enough to me you weren't judging anyone. Thank you for the exercise. It took me to a place I hadn't been before. I always appreciate that. I will look forward to more.

dko

I'm here to learn about steam and a little late in the discussion I suppose. Few questions..

The argument that the equalizer is mis-named is because it does nothing to equalize. But is that because it does nothing only in this scenario?

But given you do state, "That pressure is somewhat reduced of course by the flow of steam to the radiators, and that's why the water level at the end of the wet return rises a little, but not a lot." Does it not mean it does do something? Just negligible in your situation.

What about systems that exacerbate that exact situation and the pressure differential is greater due to more complexities such as two pipe steam and introductions of traps such as the main F&T. Or simply larger systems that the time it takes to equalize causes water level in the boiler to drop severely?

Where does the water come from that the water level in return rises? Out of the boiler correct?

Isn't that what equalizer is trying to prevent? It replaced the check valve used prior to the equalizer being developed to solve that exact problem.

So if it does provide an equal opposite force to the return to create equilibrium and prevent boiler water flowing out, is it not aptly named?

Following the boiler near piping manual, it wants you to install the equalizer regardless of your specific situation. Is it not because it wants to accomodate a number of potentially different scenarios that will still function and provide no downsides? Not every small low pressure system, properly installed and sized, would need the equalizer. Nor would any modern system need the hartford loop. But is it a negative if you did install one? But if you were to install an equalizer, simply adding a tee and close nipple at certain point between the equalizer and return inlet creates a hartford loop, so why not just do it as well? An additional safety factor doesn't hurt. Does adding an equalizer hurt the small efficient system? So creating a near piping manual with it included doesn't hurt anything.

Am I missing something here? Are all the systems worked on by everyone including Dan Holohan's with boiler water flowing out of the return a pipe dream?

Maybe i'm just not grasping something, I was just creating scenarios in my head for hours.

ethicalpaul

That's a lot of questions, @dko but I'll give it a try 😅 (although the new quoting system of the forum doesn't make it easy I'm afraid)

The argument that the equalizer is mis-named is because it does nothing to equalize. But is that because it does nothing only in this scenario?

But given you do state, "That pressure is somewhat reduced of course by the flow of steam to the radiators, and that's why the water level at the end of the wet return rises a little, but not a lot." Does it not mean it does do something? Just negligible in your situation.

No, I don't think so. I can see no operating scenario where it equalizes any pressure. Here is the original quote that I am refuting from my first post in this thread:

so they developed the equalizer pipe to replace the check valve. 

Whatever pressure appears inside the boiler will appear inside the equalizer pipe

 — if you size the pipe properly. The two forces balance each other and the water stays in the boiler.

If you look at my other thread with the video, you will see that it proved that the equalizer doesn't affect how much water gets pushed out of the boiler. I don't think it has any such effect in two-pipe systems either, although someone else will have to do that experiment if they wish to prove me wrong.

Where does the water come from that the water level in return rises? Out of the boiler correct? 

Isn't that what equalizer is trying to prevent? It replaced the check valve used prior to the equalizer being developed to solve that exact problem.

So if it does provide an equal opposite force to the return to create equilibrium and prevent boiler water flowing out, is it not aptly named?

Yes, the water from any rise in the end-of-main drip comes from the boiler. I can't speak to what the equalizer is trying to prevent, I can only tell you that it doesn't affect that water height (see my drawings in this thread or my video in the other thread).

Yes we are told it replaced a check valve, but frankly I can't think of what the check valve was supposed to prevent either. It is the end of the main itself which provides the equalizing pressure to prevent that water from being pushed out of the boiler.

It doesn't provide an equal opposite force, it provides no force and provides no equalization that wasn't already there, so no, I don't think it's aptly named.

But is it a negative if you did install one? (and additional similar points and questions)

Nope, it has other good reasons to exist and you'll note that nowhere in this long thread did I ever even hint that it shouldn't be installed. But you aren't the first to imagine that I did 😅

What I did do is to question if it actually performed any equalization, and especially if it does anything to prevent water from getting pushed out of the boiler in normal operation.

Am I missing something here? Are all the systems worked on by everyone including Dan Holohan's with boiler water flowing out of the return a pipe dream?

I wouldn't say it's a pipe dream. I would call it a mistaken understanding about the equalizer's ability or need to prevent water level rise at the far end of the main.

dko

Without the equalizer, you can call that zero force. You introduce the pipe from the header into a point on the return that was not there before. You just introduced a previously non-existent force at that location. In both scenarios, the force already exists at the end of the wet return, the equalizer merely introduced another one at the beginning of it. Just because the origin of the force is the same, does not cancel out it's existence at a new location.

Imo, it is not nothing. In your scenario it does nothing to equalize the system as a whole, but separating that specific area from the whole- it is introducing an equal force to create equilbrium at that point alone.

"Yes we are told it replaced a check valve, but frankly I can't think of what the check valve was supposed to prevent either. It is the end of the main itself which provides the equalizing pressure to prevent that water from being pushed out of the boiler."

So I think the entire argument is just this portion. I can't grasp how in every single system the end of the main will provide the same equalizing pressure. I do not think this is possible in the real world for every single configuration and system. I do not think you should use your system as a guide line for all systems, it only serves a portion of residential systems.

Those here have experience on the numerous different installed systems, undersized, oversized, improperly piped, inefficiently running… or all correct but complex, large, and with numerous other devices in the system such as system feeders, vacuum pumps.. I cannot see these systems agreeing with you on the main being able to equalize everything.

"I wouldn't say it's a pipe dream. I would call it a mistaken understanding about the equalizer's ability or need to prevent water level rise at the far end of the main."

This comment opens another can of worms?

Final question:

If every single system currently in operation had a ball valve to disconnect the equalizer from the return, are you saying there would be no problem with any of them if they were to turn the valve?

STEAM DOCTOR

Might be missing something, so please correct me if I am wrong. Equalizers were introduced in the coal era. There were no pressuretrolls and the boiler was running, nonstop, for 12-18 hours (?). Unless someone went downstairs to adjust the air shutters and reduce the flame size. Despite the 2 PSI mandate, I would assume that often, the boiler ran at significantly higher pressures. Subsequently, the "A" or "B" , were inadequate and water did end up in the main and there probably was banging. And people were probably OK with that. Was certainly better then the previous generations, who had a fireplace or two if they were lucky. In those scenarios, were there steam main, would not or could not function as the "equalizer", and water was not returning properly, the boiler equalizer was crucial, to prevent the boiler water from being pushed out of the boiler.

ethicalpaul

@dko it seems like you might not have watched my video where I showed quite plainly that that the equalizer had no observable effect at all on the pressure at the end of the main, nor at the boiler. Relatedly, it had no effect on the water levels. In short, it had no effect. If you think my experiment was flawed, please let me know how. You can see the video link here:

https://forum.heatinghelp.com/discussion/192055/equalizer-disabled-experiment-video

If every single system currently in operation had a ball valve to disconnect the equalizer from the return, are you saying there would be no problem with any of them if they were to turn the valve?

Yes I'm saying that, at least for residental steam systems. What I don't know about commercial and process steam could fill volumes.

nde

Check the WM steam vids with their demo boiler with full glass piping to see the function of the equalizer. It is most important for the first few minutes of full steam boil to equalize surging water that then settles down as steam production begins to ramp up.

ethicalpaul

https://forum.heatinghelp.com/discussion/comment/1743687#Comment_1743687

Hi Steam Doctor-
I think that's a great question. My answer is that according to my thinking and now my experiment (see my video linked in the reply above), it doesn't matter how high the pressure goes in the boiler. The water level won't rise significantly (if at all) in the return because the end of the main (which has that same high pressure) pushes down on the far end of the wet-return with the same PSI that the boiler pushes on the boiler side of the wet return (with equalizer in place or not).

dko

https://forum.heatinghelp.com/discussion/comment/1743688#Comment_1743688

I did, but it was mentioned several times that it had no observable effect on just your system and agree it should not on similarly simple systems.

But we are generalizing here and your theory it does nothing should apply to all scenarios no matter how complex. I agree for your system, as did most for low pressure straightforward residental systems.

The only thing that should be answered here is why the check valve was needed back in the day and why the equalizer was a functional replacement for it.

Your argument is that it was not functional and was pointless as it did nothing.

This is the portion I am very keen on understanding and learning about.

ethicalpaul

I really don't know anything about what they were thinking when they installed the check valve. It could have just been one dude's wrong idea.

It's interesting to note that one of Dan's sources of steam info, Frank Gerity, had this to say about such check-valves in his book, How to Get the Best from One-Pipe Steam:

If I had to guess about why the equalizer was thought to be a replacement for the check-valves I would say someone just had the wrong idea, or misunderstood something as told by someone else, and that got passed along as accepted fact and not questioned very much. That's just conjecture on my part. But I'm not the first to question it, Henry Gifford did some years ago as I recently found out.

STEAM DOCTOR

@ethicalpaul. Just thinking out loud. Just throwing out some random numbers. Pressure at the end of the main is always less than the pressure at the boiler. Because of the friction loss of the main. Let's say for argument's sake the boiler is at 2 PSI and the end of the main is one PSI. The steam will lose 1 lb of pressure due to friction in the main. That is compensated by the a dimension in a one pipe system. But let's say for argument's sake, the boiler is running at 5 PSI. Will there be four PSI at the end of the main or will the main which was never size for that type of pressure, cause greater friction loss? Maybe the main causes higher pressure loss at higher pressures. 5 PSI in the boiler might mean three PSI at the end of the main, rendering the a dimension inadequate. The equalizer would come into play in such a situation. Again I am just thinking out loud, and what I'm saying may make zero sense. Shoot away!!

ethicalpaul

I think the friction loss in the main of any home and probably many buildings is too small to be a noticeable factor. But yes, any difference in pressure between the boiler chamber and the end of the main will result in a corresponding rise in the water level at the drop to the wet return for sure.

When pressure rises, the velocity of the steam is slowed, so the pressure loss to friction will be reduced. I think when my or any system gets to 5psi, it's 5psi everywhere because the steam is not moving very fast.

In my video experiment in the other thread, and in all my time looking at my sight glass on that drop, I have never seen the water level move in any real way under normal operation, including when I force my pressure to the 4psi range. The pressure at the boiler and at the end of the main are always very close to each other.

Finally, you said "The equalizer would come into play in such a situation." My experiment proved this false. The equalizer just does not change any pressures in the system. Have a look at the video in the other thread, I know it's too long but I think it's pretty good. At the end I force a pressure differential in the main that does raise the level of the far side of the wet return.

dko

One question I have about this experiment is that they say the pipe size of the equalizer is very important.
When you forced the pressure differential by closing the valve a little, does that not change the sizing balance of everything afterwards as you are imitating a smaller riser to increase velocity.

If your headers and equalizers are piped to recommended sizes, is there a way you can force the large differential without altering anything that could throw those calculations off?

A shut-off valve above the wet return sight glass instead? to see if water level still rises

STEAM DOCTOR

@ethicalpaul. Did not have chance to watch video. Maybe later today

EdTheHeaterMan

https://forum.heatinghelp.com/discussion/comment/1743632#Comment_1743632

And we are off

to page 3 !

I love these little interactions that draw the pleasant IRE of so many! And to what end?

EdTheHeaterMan

https://forum.heatinghelp.com/discussion/comment/1743634#Comment_1743634

…and How Expensive is this Joke. I Hope we are still friends?

The Equalizer may be poorly named. I guess that when Mr. Spense taught that class, I took him at his word. Now I can see that what he was teaching is only what he was told. But it made sense at the time. I could even see the explaination in my minds eye. The pressure pushing the water level down, I have even witnessed it in a real boiler when the water dropped to the bottom of a guage glass. In my mminds eye I thought of Mr. Spense's diagram o the blackboard. the water is pushed down to the bottom of that close nipple. then the pressure icrease would not push the water any lower that that point. any higher pressure would just push the water down the return. but the water line was the samew in the boiler as the water line in the hartford loop close nipple. The water line was the same as the close nipple (Notice the I refrained from saying the "the water line was equal to the close nipple line") allowing the higher pressure to act independantly (or I might say unequally) to push water lower than the safe low point within the boiler. .

ethicalpaul

You've always been very kind and good-natured here, that's a great friend to have! I hope you liked the video!

Matt_67

Nice video! I think you've done a nice job of showing that a typical simple steam system naturally self-equalizes due to low pressure drop through the steam line. I still do believe that the equalizer is vital to operation of the Hartford loop and does in fact equalize pressures after the water falls below the level of the tee. That of course is a a safety item, not operational and as you said would take an unlikely event to come into play. Although, when you work on these things regularly you do see unlikely events, which tends to make a person more cautious.

ethicalpaul

https://forum.heatinghelp.com/discussion/comment/1743706#Comment_1743706

Just for clarity for those reading, you are speaking of when I closed the only steam supply. First, I didn't close it just a little—I nearly had to close it completely before it started to cause a pressure difference. I roughly estimate I was down to about 10% open.

Yes, that was equivalent to a very small supply riser. Probably about 1" NPT. Manufacture spec on my boiler is a single 2" supply.

I don't understand your next question…the only way to force a differential that I can think of is to alter stuff dramatically, like that supply valve.

A shut off valve on the drop to the wet return would be very strange. It would prevent condensate from returning to the boiler, filling the main with water. I think it would affect the pressure in the system in ways that I can't quite work out. You'll have to try that on your boiler 😅

ethicalpaul

https://forum.heatinghelp.com/discussion/comment/1743722#Comment_1743722

Thanks Matt. The question of the equalizer supplying a pressure relief for the hartford loop is very interesting. Others mentioned it before too. It may be that Dan and others saw info about how the equalizer "keeps water in the boiler" which was meant to be in terms of when the water levels drops due to leak and/or failure of auto-fill, etc, and maybe they generalized it to think that it meant the equalizer keeps water in the boiler all the time.

Compare the following. This tech bulletin specifically mentions when the water level has dropped below the hartford loop (which several in this thread have mentioned):

Now compare that to Dan's words from an article online which are similar to what is in TLAOSH (and this seems to match what many on the forum think/thought, that the equalizer keeps water in the boiler generally). Especially note where he says "the slightest steam pressure would push water out of the boiler and into the return". This is what my experiment disproved I think. Maybe the information above got over-generalized to the ideas below:

It's kind of a safety fairy tale either way though (as I have said in previous discussions about the Hartford Loop), because even with the water not flowing past the hartford loop to the wet return, it will get there soon enough in the form of condensation.

Rich_49

https://forum.heatinghelp.com/discussion/comment/1743629#Comment_1743629

I disagree with you about the circulator . It is not a pump , it is in fact a pressure differential machine . How bout that ? LMAO .

EdTheHeaterMan

https://forum.heatinghelp.com/discussion/comment/1743760#Comment_1743760

We will have to Disagree to agree… or is that Agree to disagree. whatever! Water in the pipes mover thingie (WITPMT). Pronounced: Wît-púmt

hot_rod

one exception, in a drainback solar, the circulator does lift the water from the drainback tank to the top of the collector. Once the water starts flowing down, a siphon is established, now the circ just becomes a differential machine overcoming the friction in the loop.

EdTheHeaterMan

https://forum.heatinghelp.com/discussion/comment/1743779#Comment_1743779

Thank You Mr. Know It All🤣

109A_5

Ponder this…

In undesirable situations the Equalizer provides a path so water can spill back into the boiler via the header when the pressure is excessive limiting the height of the water in that part of the system. The Equalizer, Hartford loop, Wet Return now behaves much like an independent Manometer with only the differential pressure of the steam main to offset the water level in that section of the system. Thus limiting the height of the water in the vertical part of the return.

Also it may be simply be 'Best Practice' to specify an Equalizer (and its size) since the Boiler's manufacture has no idea what the type or condition the system is in that the Boiler is being installed into. And you need a Header drip or drain and a siphon break for the Hartford loop anyways.

Also maybe why you don't see too many install manuals with drop headers in them.

ethicalpaul

yep, no one is saying don't install it. I said it makes a great drip in my first post.

my only issue is the idea that it keeps water in the boiler during normal operation by equalizing any pressure.

During low water condition it does equalize the pressure in the Hartford loop only so that might have been the origin of the name but it's clear that at some point its influence was over-generalized. Thanks!

jumper

Suppose there is a primary circulator & some others somewhere. When those secondaries overwhelm that primary there can be a flow problem rather than a lift issue.

Rich_49Mar 21, 2023

https://forum.heatinghelp.com/discussion/comment/1743629#Comment_1743629

109A_5

Hello @ethicalpaul,

Did you notice on this post below, No header, No Hartford loop, No Equalizer, No check valve, but it does have a Expansion tank. And apparently no complaints about its operation. Maybe an Expansion tank is the ultimate fix, who knew.

https://forum.heatinghelp.com/discussion/192060/old-national-u-s-radiator-residential-boiler-question

ethicalpaul

I saw that one @109A_5 ! Any time any of us have differences of opinion, we should remember that there are always thinks out there that we can all agree are pretty crazy! Have a great week my friend