Converting from EG-45 to EG-40.

ChrisJ

After thinking about for a long time I've finally decided to do it.

I'm swapping my EG-45 6 tube burner out for an EG-40 5 tube burner as well as the drafthood. Not sure why the drafthood matters but for the cost I'm doing it being they are different between the two boilers. This will 100% convert my EG-45 into an EG-40.

This will reduce my boiler from 150,000 btu input down to 125,000 and it will also reduce my pickup factor from 33% down to only 10%.

Why am I doing this?

Because the radiation is oversized for the house (94K when I need 62K).

My expectations are for slower heating, perhaps lower pressure and to maintain my perfectly even heating throughout the house. This should make it easier to maintain a tighter temperature swing in the house.

I am not doing this for lower steam pressure. I am doing it primarily to slow down how fast the system heats the house.


I will let everyone know what the results are. The parts unfortunately will take 2-3 weeks to ship but have been ordered.

Fred

OMG! That system is probably saying UNCLE, UNCLE, UNCLE!

Fred

I know how you feel about Pick up factor but keep in mind, the boiler still needs the capacity to heat the Mains, header run-outs and radiators from a cold start AND you need to ensure the capacity is there to maintain the temp of the Header, Mains and run outs during any heating cycle. Even though they may be insulated, they still condense at a level necessary to maintain a pathway hot enough to deliver steam to the radiators. Is 10% enough? I don't know.

KC_Jones

Chris just can't stop tinkering with things. If it does work you may even see a slight decrease in your gas bill.

ChrisJ

Fred said:

I know how you feel about Pick up factor but keep in mind, the boiler still needs the capacity to heat the Mains, header run-outs and radiators from a cold start AND you need to ensure the capacity is there to maintain the temp of the Header, Mains and run outs during any heating cycle. Even though they may be insulated, they still condense at a level necessary to maintain a pathway hot enough to deliver steam to the radiators. Is 10% enough? I don't know.

Fred,

Remember, we heat the piping little by little just like the radiators. Even with those pipes ice cold even the smallest boiler could heat them given enough time.

Yes, I agree the pipes loose some heat even when insulated. I expect that number to be somewhere around 5000-10,000btus depending on the ambient.

As I said the radiation is too big for the house (94,000 vs 62,000 required @ 0F). Using that number the boiler will still be 42,000 btus too big so plenty left for piping losses. I suppose this will somewhat prove my feelings about a pickup factor and if I find out I'm wrong I'll fess up.

If it works as expected I may have a pro come in and reduce the manifold pressure to reduce the output even more. I'm trying to make the system not so picky about run times more than anything.



And yes, I can't stop tinkering. Probably never will, it's just the way I am.

Dave0176

Well Chris, you can always strip her down and remove a section, and drop another burner, after all it is a Weil McLain, a lot easier to take apart and reseal then a push nipple boiler!! Lol

Dave0176

Or I just thought of this, just remove all that pipe insulation and have a toasty basement.

ChrisJ

MarkS said:

And after that, if you get bored, you can start removing radiator sections.

You do realize I have considered that right?
The problem is 9 of my 10 radiators use the threaded couplers rather than push nipples.

KC_Jones

Change out all the rads for smaller ones then. lol

Fred

Lord help me

JStar

Changing the burner tray is the same work as changing the GCV. We do it all the time for oversized boilers. Changing the GCV won't affect the firing rate, though. Swapping the orifices can lead to some undesirable burner patterns, too. Really, the safest way to downfire this model boiler is to convert the burner tray, and remove one burner.

ChrisJ

It took me a while to find the thread, but the whole pickup factor had been discussed a year ago and Gerry Gill posted a wonderful article about it.

http://forum.heatinghelp.com/discussion/149940/pickup-factor-help-me-understand#latest

A direct link to the article it self.
https://www.ideals.illinois.edu/handle/2142/4349


Here is a snip from the article.
Keep in mind, my radiation as well as many others are already oversized for the home so we shouldn't need extra capacity to bring the home out of setback at design temperature.

Furthermore, is it not standard practice today to not do a setback when temperatures will be near design temperature because the systems won't be able to handle it? This snip is talking about at or near design temperature if I understood it correctly.

ChrisJ

MarkS said:

Those University of Illinois Engineering Experiment Station bulletins are absolute gold.

ChrisJ said:

Furthermore, is it not standard practice today to not do a setback when temperatures will be near design temperature because the systems won't be able to handle it?

How does the thermostat (in charge of the setback schedule) know it's at or near design temperature outside? I doubt most people override the thermostat unless they know from experience that their system has a problem recovering.

I don't know.
I just recall asking about this in a thread last year when some guys were saying they had customers systems running at design temp. I figured, if the system runs 100% at design temp, how can you do a recovery and basically the answer was you can't.

ChrisJ

Curious if this animated gif will work on here.

Fred

@Chrisj , the nice thing about your approach is that you will have the old burner tray and can re-install it if things don't work out. A little time but that's a nonimal price for experimentation.

ChrisJ

Fred said:

@Chrisj , the nice thing about your approach is that you will have the old burner tray and can re-install it if things don't work out. A little time but that's a nonimal price for experimentation.

Those were my thoughts exactly.
Out a little money and time, but will have learned something in the end.

SWEI

Total cost of the replacement gas valve, new burner tray, and gas hood?

ChrisJ

SWEI said:

Total cost of the replacement gas valve, new burner tray, and gas hood?

Same gas valve.
New burner manifold, rear burner support and draft hood prices are cheap. I don't want to say them as Dan does not want pricing discussed on here but they are not expensive.

ChrisJ

Hatterasguy said:

My concern with such a philosophy in a larger building would be the inability to balance the system with radiator vents. To properly direct the steam to individual radiators by varying the venting rate requires the steam to actually arrive at all the radiators.

Even with my current system that generates 2 ounces, I'm a bit concerned that I cannot easily control individual radiators effectively. I have not had the opportunity to confirm this, however.

It will be interesting to see if the control of individual radiators is lost once the steam takes its leisurely stroll down the pipes.

I'm of the opinion that a higher pressure (2-6 ounces) is desired to rapidly bring steam to all the radiators and, once achieved, the firing rate should be reduced to maintain it.

Right now my opinion is the different vents are just effective at very low pressure as they are at very high pressure. I don't see why they wouldn't be as everything is relative.

SWEI

Somehow I thought you had recently replaced a noisy gas valve -- sorry.

ChrisJ

Hatterasguy said:

ChrisJ said:

Right now my opinion is the different vents are just effective at very low pressure as they are at very high pressure. I don't see why they wouldn't be as everything is relative.

If all the rads see the same low pressure, I agree.

But, the question begs on how much pressure is lost during the ride to the rads? This would depend on the size of the building.

If you run, say, 4 ounces and you lose .5 ounces on the way, the loss is insignificant.

If you run .5 ounces and you lose .5 ounces on the way to the furthest radiator, you're going to have problems.

Trying to get to ever lower pressures ignores the pressure drop in the delivery system. I'm sure it's not 8 ounces as some older texts would state, but I'd also suggest that it's not .25 ounces either.

I think you are correct, there must be a drop due to friction.

I thought something said pipes were sized for 1 ounce per 100 feet?

ChrisJ

SWEI said:

Somehow I thought you had recently replaced a noisy gas valve -- sorry.

Oh I did, I replaced it back in November I think with an exact match.

ChrisJ

No balancing issues at all right now.
Everything is practically identical.

ChrisJ

Vents based on performance rather than just radiator size. This took a very very long time to get where it is.

I've been considering installing vents on the pipe side of some of the radiators to vent the piping faster and then using a slightly slower vent for the radiator it self. Such as on my upstairs bathroom, downstairs bathroom and small bedroom.

JStar

In my experience, lower pressures = greater distribution equality. Low pressure steam creates less steam per volume, which moves faster, and has less of a heatloss-to-volume ratio than high pressure (higher capacity per volume) steam. Higher velocity at a lesser heatloss = higher steam capacity at the furthest radiators. Radiator vent sizes then become a constituent of the system's total resistance and not just a regulator of its volume of air. Radiator vents control the Delta-P of steam. We could look at radiator vents as a calculated restriction of air and not just an effectively-positive relief of air.

So, what does this mean? I've found that most systems can operate on pressures that are much lower than I would have expected from the traditonal rule of 2oz/100ft of piping. We'll often see radiators filled 100% with steam on less than 1 ounce of pressure. All we usually need is some number greater than zero to make steam move.

And think about two-pipe steam. How can you DOUBLE the amount of piping and fittings in a system (separate returns) and still make it operate more evenly on lower pressures than a one-pipe system? The answer is by having less resistance at the radiator outlet. Less back-pressure on the incoming steam. The return oultet appears to be relatively negative to the steam's pressure. Radiator vents change the steam's perceceived measurement of atmospheric pressure outside of the radiator. That's also the principle of induced vacuum systems. You can change Delta-P on either the inlet or the outlet. Humans can only see positive and negative pressures from our own atmospheric views of meaurement.

Of course, having all of your pipes insulated, correctly pitched piping, minimal fitting arrangements, and a properly sized boiler will be essential in maintaing the lowest pressures possible. However, it's not terribly difficult to rewrite the thin line between engineered theory and practical application.

So, for the TL;DR version: Low pressure steam, carrying an adequate capacity, is almost always good.

JStar

ADDENDUM:

On the topic of friction loss in the main piping, specifically, I think about the steam losing capacity as it gets further out into the system. What happens there, is that it will turn into condensate which will creating a lower pressure in that area of piping, causing more "higher" pressure steam to move into its place. This will continue to happen until steam reaches the end of the mains, and begins to travel to the radiators. So, the portions of the steam main with the highest resistance will form condensate at a faster rate, which then unfairly drags more steam in to take its place. In this way, a system could achieve a sort of self-balance to a certain degree. I'm sure, though, that there is a tipping point, where the resistance in one part of a system far outweighs that of another and completely destroys the overall balance.

ChrisJ

Hatterasguy said:

JStar said:

I'm sure, though, that there is a tipping point, where the resistance in one part of a system far outweighs that of another and completely destroys the overall balance.

That's the question.

Where is the tipping point?


Clearly it's well below 2 ounces. Getting steam to all rads at 2 ounces is a certainty.

Now, whether you can do at .25 ounces? That's the question.

Maybe Chris will provide a solid answer for that.

If you can balance a steam system at .25 ounces, that completely changes the entire game with regard to controlling pressure with a Pressuretrol or a Vaporstat. Neither one can effectively be utilized.

My own system takes 30 minutes to go from .5 ounces to 2 ounces on high fire. Imagine if I could cycle between low and high fire once .5 ounces was achieved.................

Why haven't you tried it?
What vent is on the radiators you say are hard to heat? Are the risers vented?

ChrisJ

Hatterasguy said:

I'd need the Dwyer-Stat to do it.

And, I cannot seem to control my boiler water to the point where the surge is reduced sufficiently. Every couple of weeks it gets a bit out of hand and needs skimming to keep the pressure below 8 ounces.

This boiler would function fine in any other installation. I just cannot seem to get it to behave for the long term. I must have skimmed it 15 times. Always successful after the skim.

6's are on the third floor. Those rooms are now fine.

6's as in Gorton 6s?
I have Gorton Cs on some of my second floor radiators.

To me, it sounds like your boiler needs the Gerry Gill Wand© treatment.

Mark N

Chris are you still using Gorton C's on the 26.6 sqft rads? The C vents nearly as fast as the Gorton #1. I have 2 rads in my office at work that both have C's on them. They are each old column style rads of 90sqft EDR.

ChrisJ

Mark N said:

Chris are you still using Gorton C's on the 26.6 sqft rads? The C vents nearly as fast as the Gorton #1. I have 2 rads in my office at work that both have C's on them. They are each old column style rads of 90sqft EDR.

Yep, that map is 100% current.
A Gorton C isn't that fast at 1" WC.

vaporvac

@Hatterasguy‌ , I use my wand through the skim port. Maybe that would work for you

ChrisJ

Hatterasguy said:

The skim port is 1.5". It is directly inline with the push nipples. It's about eight inches in to the first section and another 22" to the last section. The wand would need to make a sharp 90 degree turn southbound in each section to get to the bottom.

It doesn't sound like I could be effective with the wand in such a scenario but I'm all ears if you can explain how to get in there.

I use my 1.5" skim port as well. It's all I've ever used.

KC_Jones

On my wand I have a 1/8" hole in the end for the water to come out and it will shoot a good 50-60 FEET coming out of that hole. That also depends on what kind of water pressure you have available. I was able to blast the inside of mine multiple times and got away with 3 skims after that. So far so good.

KC_Jones

This was the first bucket I pulled from mine. As you can see that wand can definitely get some crud out.

ChrisJ

MarkS said:

I don't know about 1/4 ounce, but I'm getting steam to all rads with around 1/2 an ounce (0.8 in WC). And with 135 feet of mains piping, the 2 oz per 100 ft rule is busted, at least in my house.

@MarkS do you ever have problems with your rad vents getting clogged with a drop of water?

When I had Hoffman 1As on everything this happened completely random, and often enough I switched to Gorton vents. With Gorton's it still happens, but very rare. Maybe once or twice a year? Because it was a constant problem with the 1As I learned to use a van of air with the straw to blow the drop out and I'd get heat instantly. The few times it's happened with the Gortons I just flick the vent with my finger a few times and it's back in operation.

Seems like Gorton is the vent choice for low pressure.

By the way, what makes a "vapor system" a vapor system? Does it have to run in a vacuum, or is there some other definition?

ChrisJ

MarkS said:

I don't know if it's water but I have one Gorton rad vent that once or twice a season gets stuck closed, and I need to spin it upside down then right side up again.

Vapor, according to this article, is any system running at very low pressures, < 16 oz.

So does that mean we both have single pipe vapor systems?

ChrisJ

The system has only run two times so far, once to bring the temperature up from 62F to 66F and then I decided to shut down for a half hour and restart just to see how it behaved from a normal start. I had a TRV shut due to the sun heating the room and it made me concerned but once I cranked it up the radiator got steam fine.

This is my pressure near the end of a 30 minute run time.
Right now, I couldn't be happier with the performance.

http://youtu.be/uDWNwirGkTk

Fred

Way to go! Next test will be on a design day.

ChrisJ

Pictures.

Original burner




Manifolds side by side.




They raised the bung height so I had to go by a 3 1/2" nipple to make up for the difference.




New burner




Original drafthood



New drafthood




Inside the EG-40 drafthood. It's a lot different than the EG-45.

ChrisJ

Fred said:

Way to go! Next test will be on a design day.

Not really,
Design day for here is 4F. According to my heatloss and the size of my radiation I'm still good down to around -44F.

As long as the radiators heat balanced, which they appear to, the system will sing on a design day doing a 10 degree recovery.

KC_Jones

And you even added the music to the video...lol. Glad it went well! Now to see how it performs!