Equalizer disabled experiment video

Thanks Rusty!

Don't give me too much credit—that's the beauty of having a steam boiler in my house and working in a different industry, so when I get home I'm not sick of the topic 😅

Note that I don't think it doesn't have a function—it is a great drip from the header and there are edge cases where it will prevent the hartford loop from having an air bubble in it. I'm not sure when it got this name but apparently old books called it a "bleeder" or "drip".

What I hoped to show (and I think I have shown) is that it seems NOT to have any effect on the thing that the industry currently thinks is its most important function, to prevent the water from being pushed out of the boiler under normal operating conditions. Thanks again for your note.

Thanks for your note @Gsmith. I have never observed a partial vacuum in the main while the boiler was steaming. I've had that sight glass on my end-of-main drop for years, have observed it throughout many complete cycles, and have never seen the water level reach it except when I perform the very weird and unusual step of closing that supply valve as I did in the video explicitly to force the kind of pressure imbalance that the Equalizer was purpoted to prevent (but has no effect on as shown in my video).

I think the equalizer really does provide pressure equalization and prevents the water from leaving the boiler. 

Respectfully, I think I proved otherwise. I'll leave the valve closed for the rest of the heating season if I thought that would convince anyone 😅

Maybe think of it as you point out as simply a drip, which besides returning water from the header also helps equalize the steam and system pressure.

Yes, it's an excellent header drip. But I won't think of it as equalizing the steam and system pressure, because as shown in the video, it has zero effect on any pressure in the system. Thanks again!

Hi Scott! Just to clarify, yes I think it's mis-named, but the bigger importance is that lots of people believe that it has some effect on the pressures of the steam system, where my drawings and now my experiment seem to show that it has no effect.

Sure, I can run a heating cycle with the valve closed. Would you like to see my normal very boring heating cycle with 1" of WC pressure, or should I close a bunch of my radiators again so we can see some pressure build up?

It sounds like you are thinking that if the valve is closed from startup that it will indeed result in a pressure differential that will drive lots of water into the main where it will cause nasty hammer. I'm pretty sure it won't but I'm happy to run that version of the experiment and record it, thanks!

Hi Chris, happy to run and record that experiment.

Side issue—I do think it's a myth that there is more condensation in the main during a cold start. Compare the EDR of a main against the EDR of all radiators in the house fully condensing late in a heating cycle. There's no comparison. But the difference probably isn't that great either way…remember, the boiler creates steam at the same rate no matter where in the heating cycle so really the condensation must be about the same (until full steam saturation through the system and resulting pressure rise)

Also, you probalby don't want to test this, but would you agree that a break in the wet return (e.g., with the boiler off) will drain the boiler if the equalizer valve is turned off (the water syphons out) but not if it is on.

I think it probably would, yes, but the boiler will drain anyway relatively quickly due to steam production. I'm not sure why everyone keeps bringing up broken wet returns, it's not really related to the error I'm trying to address that the equalizer keeps water from being pushed out during normal operation. Just how often are everybody's wet returns breaking anyway?? 😅

I did run the experiment that a few people asked for where I closed my equalizer valve at the start of a call for heat, and kept it closed through the entire call to see if anything interesting would happen. Nothing did!

Warning, this video is extremely boring, but if you love watching boilers boil with annoying commentary, feel free:

Thanks @109A_5 , I agree with you about the near piping filling with water if I were to leave that valve closed.

And yes I agree about the correct location of the King Valve. The reason I put valves where you see them on my steam supply was so that I could see if there was any difference in performance with one supply vs two. See my earlier video entitled "Are the manufacturer's specs enough to make dry steam?" or something like that.

In my case, the spec calls for just a single 2" supply and I found that was just fine.

Thanks Scott, I do have a huge advantage living with this thing! Just ask my wife, it's definitely part of the family!

I do have to repeat, I have never suggested not installing the equalizer. It has several nice things about it that advantage it over those installs without one (I think the most important one is as a header drain), so you're preaching to the choir there 🙂

Can we assume that there was a lot more condensate in the single return than normal, as the equalizer was closed? Maybe not, as there appears to be litte carryover once the near boiler piping was fully warmed up.

If you mean was there a different amount of water in my wet return, I would say no. The only difference I saw was that with the valve closed for the entire call for heat, condensation from the equalizer did pile up in there as you expected. I would say there was zero carryover…the water that was in my header was from condensation as the header and nearby pipes were heated from cold.

 In addition, for the typical seven radiator house (three bedroom, one bath) around here, the 1.25" wet return is about twenty or thirty feet long (yes prone to clogging/rotting).

Yes I see that. Mine is shorter than it used to be since I improved my end-of-main situation. In my house, the main makes a partial tour around the basement and ends up very close to the boiler. The wet return is now so short I even made it 1". I also have the water feed located over there connected to a tee at the bottom of the end-of-main drip, so I can open up both ends and shoot water through there, but it stays pretty clean just with occasional opening of the cleanout valve on the boiler side of the return.

We also almost never install a cycle gaurd on any system, I personally do not like the concept of turning a steam boiler off while it's trying to warm a house (and the pressure is still very low). I'm not sure any of this makes a difference.

I didn't choose to install it, it came on the packaged boiler from Peerless so I left it on there because once I saw it operating, it didn't bother me. They have an optional wiring method where the timer of the Cyclegard resets at the start of a call for heat. Honestly I can't imagine why they don't come with that feature enabled from the factory, it would make the device much less hatable 😂 Overall though, it is a very very safe way to check for a good water level, and the way most people never look at their water level for months or even years, I can't argue with the lawyer who designed it 🤣

Thanks so much for your comments and all the good work you've done here in NJ!

Sure I can do that, but the water line was stable as always. I don't blame you for not watching the whole thing! On the actual youtube.com page for it there are links to the different parts.

I'm still thinking about what Mr. Spence taught you, Mr. Ed—

The way it was explained to me, back in 1974 by Mr. Spence, who was in his late 60s at the time, (he qualifies as one of the dead men) that the <5 PSI that you have provided in your drawing can only be 4 PSI or it can also be 3 PSI requiring a greater dimension "A". Some designers operated their boilers well over 5 PSI back then. This would create the potential for a 3 or 4 or even 5 PSI difference in the steam pressure at the far end where the column of water at the other end might be 9 feet.. That much pressure difference could lead to catastrophic boiler failure about 2 to 3 times a week. 

So he did teach that there could be a large pressure difference at the far end of the wet return that would result in a need for a greater dimension "A"?

Do you recall what were the situations that could lead to that large a pressure differential? The only way I can get anything more than an ounce or so of pressure differential (even while I have 5psi) is by closing off my equivalent to the "King" valve while the boiler is running (not advisable unless with extreme caution)

I have thought about that and seen a few people mention that.

Let me share my thoughts on it: (all these assume a failed LWCO)

Without a Hartford loop or EQ a leak will drain the boiler

With a HL loop and no EQ a leak will drain the boiler and probably act as a siphon too but probably won't be much different from above

With both, a leak will drain the boiler to the HL line and then when the boiler fires, the rest of the water will get transferred as steam to the leaky return anyway

Finally this weird case: if you have a HL and no EQ if you fill the boiler from empty via the wet return as my setup would do, you will get an air bubble in the HL that might cause issues.

I still see these as edge cases with the main purpose being a header drain.

Just how many catastrophic wet return leaks with a failed lwco are happening? Remember even with Hartford loop and EQ the resident would have to inspect the boiler before the water steamed out to prevent a dry fire. Good luck!

@EdTheHeaterMan I read your interesting story with appreciation! I don't think it applies to my question of "does the equalizer affect how much water gets pushed out the wet return of a boiler in operation?" (see @EBEBRATT-Ed 's statement above for what I'm talking about) but I appreciated it none-the-less!

But there is no low pressure. In my experiments up to 5psi, the pressure is nearly identical at the boiler and at the far end of the main. The water line at the far end of the wet return doesn't budge. That's the question—what is the circumstance where there is a large pressure difference?

I have a suspicion that when people saw water squirting out of their main vent, and the water level at the boiler dropping, they were really seeing surging and they blamed it on some kind of pressure issue instead.

Then they said "we better install a check valve". Then it still happened and/or their valve caused actual pressure problems. Then they tried the equalizer design and it shunted the surging water back to the boiler instead of up the main and they said "this thing fixed our pressure problem!! Let's call it the Equalizer!" This is total conjecture on my part LOL

@109A_5 thanks for the reply

I think for you to posibly 'see' what you want to see you need to do two things. A valve between the header and the main for the purpose of building pressure and leave your riser valves fully open, and a sight glass like your others either where your equalizer valve is now or just above it. So that the bottom of the sight glass is at about your normal water line level. Your equalizer valve could be above the sight glass.

With the valve in this position you can make a much more dramatic pressure differential between the Near Boiler Piping as a whole and the Main.

Well that would be artificial. Why I'm asking is that people have told me that there are situations where a boiler will push water out of its back, into the wet return, raising the level of the water at the drip into the wet return at the far end of the main. I have not been able to repeat this in experiment, either mental or real-world. So that's why i keep asking how can it happen, so I don't look like a fool going around saying "it can't happen". I am open to the idea that it's possible outside my little basement, but I just haven't heard what might cause it in normal operation or even occasional abnormal operation.

I think my 3psi gauge was fine after going to 5psi.

I look at it this way, with no equalizer, the surface area (Square inches) of water exposed to the steam pressure in the boiler is huge as compaired to the surface area in the vertical return pipe. So with the boiler's pressure lowering the boiler's water level (a small deviation, since water does not compress and does have a place to go) and with the pressure differential across the system it will greatly raise the water level in the vertical return pipe until the weight of the water causes an equilibrium. Adding the Equalizer pipe with a normal header does a few things, limits the water height near the boiler (it can spillback into the boiler via the header) and adds more (Square inches) of vertical pipe outside of the boiler.

Its like a Manometer with a pressure source in the middle of one of the vertical pipes, except with a Manometer usually the tube is the same diameter on both sides.

Also I suspect older boilers had much larger surface area of the water as compaired to newer boilers so the effect was greater with the older boilers. Since Paul's boiler is newer and small it will be harder to see the effect.

There is no effect. The pressure during operation of my boiler, from cold start to full steam, 0psi to 5psi shows no measurable or observable variance in pressure between the steam chamber and the end of the main. If there were a differential, we'd have seen the water level rise.

Only by artificially limiting the flow of steam to my header was I able to force a difference to occur.

I think in any residential system with properly sized pipes, there is going to be no measurable difference and no water rise. As the capacity grows, the main gets bigger, the wet return gets bigger, everything gets bigger which reduces any friction or delay in transmission of the pressure from the steam chamber to the far end of the mains.

So I'll just keep asking for awhile: What is the situation in non-residental steam where those two pressures can vary?

How about in the case of a condensate pump/storage situation?