Reccomended Single-pipe steam boiler accesories?

cubicacres

With our 780 sq ft single-pipe steam boiler install project, would you reccomend for or against adding the following items, or have other suggestions?
1. Reservoir/condensate tank (no pump needed with natural gravity return on single-pipe system)
2. Vaporstat with 1-3 psi meter
3. water meter to help detect leaks sooner
4. Two 3 inch or larger risers at least 3 feet high, with a drop-header setup
5. 4 inch or larger header pipe
6. Vari-vents for the warmer 2nd floor rooms
7. Anything else or different form this setup assuming we have a good install and the right size gas boiler?

vaporvac

I think the risers are generally determined by the boiler. Just be sure not to downsize. As I mentioned in your other post, clean the wet returns and you probably won't need a condensate tank. That's something you can plan for and add later if you find you need it, (but you probably won't). I mentioned the Slantfin Intrepid on the other post... do you have your installer already?

nicholas bonham-carter

Don't bother with a condensate tank, until there is a clear need for one-probably never.
Double check your EDR calculations for the new boiler size.
All the other things on the list are needed, along with massive main venting. you may need up to 8 Gorton 2's on the dry returns, and they will be money well spent.--NBC

ChrisJ

I highly recommend TRVs for the warmer rooms. Slowing up venting on radiators in warmer rooms often won't work. Colder days with much longer run time allow the slower vented rads to catch up to the other ones which still causes overheating.

Overheating means your money is going through the walls and ceiling faster and likely out the window as well.

You still need to vent at different speeds, that won't change but a TRV keeps rooms from getting heat when they don't need it. When most of my house is at 72F two of my bedrooms are at 64-65F thanks to TRVs.


Some say they aren't worth the money but I have two in my single family home and want to add two more. I hate heating the radiators in the kitchen when the oven is going for no reason and TRVs will put an end to it. The kitchen also has a lot of sun exposure.

If you want more information on what to by I'd be glad to help out.

RobG

@Chrisj , Why is your oven running for no reason?

ChrisJ

RobG said:

@Chrisj , Why is your oven running for no reason?

My opinion and my wife's opinion differ greatly at times...

RobG

ChrisJ said:

RobG said:

@Chrisj , Why is your oven running for no reason?

My opinion and my wife's opinion differ greatly at times...

Nothing a $200,000 dollar lawyer and an appliance repairman can't fix.

JUGHNE

ChrisJ, could you heat the 2 bedrooms to 72 degrees, as the rest of the house, with your reduced burner size and low pick-up factor? Or has that already been tested?

You aren't heating your kitchen with the oven door open, are you? I know, I know.

ChrisJ

JUGHNE said:

ChrisJ, could you heat the 2 bedrooms to 72 degrees, as the rest of the house, with your reduced burner size and low pick-up factor? Or has that already been tested?

You aren't heating your kitchen with the oven door open, are you? I know, I know.

The radiation in the bedroom is grossly oversized, I guess due to open window rules? Not only can I heat them to 72F, I can heat them to 72F in one cycle if I turn the TRVs up. I know this because I had a fever one night and was shivering terribly so I turned it way up. I think it had it up to something like 75-76F and it did that in one cycle from 64-65F.

My system can fill the radiators no problem. Remember, 104,000 btu DOE output into a system that can only condense just over 94,000. There shouldn't be any doubt here. My piping doesn't use over 10,000 btu, more like 1500.

JUGHNE

I ask because at what point is a boiler really too small? As in Dan's TLAOSH he mentions a boiler undersized to where it will not produce steam but just "simmers" and barely heats the house.
So if we were to assume/calculate that most radiation is oversized for the building because of "open window designing" or building envelope upgrade; then could we just count just say 80% of the EDR of a single pipe system. The rads may never heat completely across but we don't need it. So we use 80% of connected EDR with calculated insulated pipe losses as additional connected EDR and use no pick-up factor added?
You owe it to the steam world to downsize your boiler by another burner this winter and let us know!

Dave0176

JUGHNE said:

I ask because at what point is a boiler really too small? As in Dan's TLAOSH he mentions a boiler undersized to where it will not produce steam but just "simmers" and barely heats the house.
So if we were to assume/calculate that most radiation is oversized for the building because of "open window designing" or building envelope upgrade; then could we just count just say 80% of the EDR of a single pipe system. The rads may never heat completely across but we don't need it. So we use 80% of connected EDR with calculated insulated pipe losses as additional connected EDR and use no pick-up factor added?
You owe it to the steam world to downsize your boiler by another burner this winter and let us know!

No Chris can't lose another burner unless he removes an intermediate section to downsize to the the 3 section EG35, but then he'd need a new front and rear panel, new front door, new draft hood inside and out, ahh it's not worth it. lol

ChrisJ

If someone donates a new smaller boiler or one with a power burner I'll consider using it

JUGHNE

Just stirring the pot, I was surprised that WM would approve the downsizing with the removal of one burner. So the next thing that ChrisJ could do to trim the system a little more would be a 2-stage gas valve?

So on boiler sizing then the connected EDR must be considered and weighted against the actual heat loss of the structure (with the windows closed ).

Also heat loss of insulated pipe. There are charts of heat loss by temperature differences, but is this accurate as the steam is condensing in the piping until temp is reached? The BTU's given up by phase change with little temp dif. So is there a EDR chart for insulated piping?

Chris's approach to TRV's controlling a slow rad vent sounds to be the approach to air control with limited steam.

Also, then you have to convince the customer that the rad does not need to heat all the way across like it used to, just before he opens the window.

ChrisJ

JUGHNE said:

Just stirring the pot, I was surprised that WM would approve the downsizing with the removal of one burner. So the next thing that ChrisJ could do to trim the system a little more would be a 2-stage gas valve?

So on boiler sizing then the connected EDR must be considered and weighted against the actual heat loss of the structure (with the windows closed ).

Also heat loss of insulated pipe. There are charts of heat loss by temperature differences, but is this accurate as the steam is condensing in the piping until temp is reached? The BTU's given up by phase change with little temp dif. So is there a EDR chart for insulated piping?

Chris's approach to TRV's controlling a slow rad vent sounds to be the approach to air control with limited steam.

Also, then you have to convince the customer that the rad does not need to heat all the way across like it used to, just before he opens the window.

Controlling a rad with a TRV is a standard approach and works at 1.5 PSI as well so I'm not sure what you mean? I'm using TRVs to control two oversized radiators that constantly overheat the rooms in colder weather even with slow venting. The bonus I found out, is that they also stop problems if the sun is warming the room, so hey, more money saved and greater comfort.

Also, WM designed the boiler to be used with 5 burners or 6 so I'm not sure why you're surprised? The EG-40 and EG-45 are identical other than burner manifold, burner rear support and drafthood. You changed those, and you can have either boiler. They are even shipped with the same tag, mine shows ratings for both and says to count the burner tubes.

Regarding removing a burner and plugging the port, I won't do this as Jstar told me not to a year ago. He said it could cause problems so I won't do it.

Stirring the pot is not beneficial to the forum and I doubt will help anyone in the long run.

JUGHNE

Chris, this is not anything personal towards you. I follow most of your postings because there are few steam systems that are being constantly upgraded. I have learned a lot with your changes as far as ultra low pressure and pick-up factors.

Just today "stirring the pot" a little has:

Given us Hatterasguy's opinion on pick-up factors, which was what I have always thought about oversized EDR.
Shed more light on TRV's for one pipe steam, I'm familiar with their use but HO reading may not be.
Told the wall about WM's EG-40 and EG-45 being the same block and interchangeable burners. (Someone may want more iron and water and get the EG-40.....knowing that if it does not fit the bill they may upgrade it to a 45 for a little money.)
You must not have seen the humor intended about dropping another burner for this winter. Have you considered the 2 stage gas valve?
There were old boilers that came with one burner tube missing and a plug in the manifold. Lots of iron that maybe didn't notice the uneven burn. I would not do this with newer equipment today.

If you even ask most tech service reps/engineers about downsizing any forced air unit they will just about hang up on you. Even though all the hardware components are the same and you only want to put in smaller orifices, they don't want to be a part of it.

Forum: Any public meeting place for open discussion.

Stirring: 1. Rousing; exciting; thrilling. 2. Active; lively.

cubicacres

Thanks for all the great advice. We're getting a few more bids and waiting to see if we can get some financial assistance from our Focus on Energy program here in WI if we can get our AFUE higher. Does anyone know if we can get better than 83.4% AFUE for a single-pipe steam system with 780 EDR, heating a 2 story brick 4,200 sq ft building with 5 1-2 bedroom units here in Milwaukee? The Utica PEG299EID we saw that was not reccomnded, but had the highest AFUE so far in our research. We didn't see any dual or modulating burners yet.

ChrisJ

Steam heads recommendation Will likely get you in the 85% range

cubicacres

The Weil-McLain 3-80 with a power gas burner? I'm having some trouble finding the specs on that boiler at their website. How do the power burgers differ from the ones on an EG 65 or EG75?

cubicacres

(burners, not burgers :-) Is that an over-sized boiler at full capacity, but able to be scaled down for better matching of steam needed than a single-stage EG-65 or EG-75, hence the higher AFUE?

ChrisJ

@Steamhead will need to help you with those answers. I have no experience with such systems.

As far as how does it compare to the EG series, it's completely different. It's a boiler intended for use with an oil burner and instead you use a gas power burner which is more controlled.

I can say they appear to rate it at 85% AFUE.
http://www.weil-mclain.com/en/assets/pdf/80_lit.pdf

cubicacres

Regarding proper sizing, If I take the EDR sq ft measurements of all the radiators and divide by 1.33 to fully eliminate the 33% pickup factors, then add 10% for only the piping pickup, is that (780/1.33=586x1.10=645sq ft) the ability to heat all of the radiators 100% up and the piping on design day assuming piping is average size & insulation is good? This would effectively be about 23% smaller than the simple EDR measurement which is 780 sq ft in our building (the sum of all the radiators).

Depending on if I size the boiler for a total pickup factor of 33% (10% piping & 23% safety margin) or 10% (piping only), will the pressure-troll kick off the boiler at cut-out pressure frequently if it's over-sized (an EG-75 producing more steam than needed vs. EG-65 being a closer fit assuming the above comments are correct for sizing, for example)?

Fred

The 33% pick-up factor is already built into the boiler and not counted in the 780 EDR Rating. The boiler is actually the equalivant of 780 X 1.33 = 1037 or 249,000 BTU output. To get a 10% pick-up factor it is 780 X 1.10 = the equavilent of 858 or 206,000 BTU output.

cubicacres

I see...that would explain math of the rating chart in the manual for the WMC EG-65 boiler. 654 sq ft x 240=only 156,960BTU DOE Heating Capacity Gross Output, not the 209,000BTU DOE Heating Capacity Gross Output as listed in the manual.

Take the Sq ft number of each boiler in the manual, multiply by 1.33, then by 240, and you get the DOE Heating Capacity Gross Output, right? Is this the same calculation for most steam boilers?

Fred

The EDR calculation is the same for all steam boilers.

cubicacres

Per WMC, each boiler size up has more burners (65, 75, 85), but the 75 has a higher Gross Output (s/b 247,00 per WMC, not 240,000), and Sq Ft is 770 on 75 vs. 760 on 85. A different rep said the over 300,000 BTU boilers are commercial and don't include the spark ignition & automatic draft hood which increases the 75 & lower model's efficiency & output ratings. Would this explain the appearance of the 75 looking like it can heat more area than the 85 in the attatched PDF chart?

cubicacres

ok-that matched what WMC just told me on the tech line-the vent damper & spark ignition are included in the EG models, but not the EGH. With 780 sq ft of radiatiors, they thought either one would work (EG75 @ 770, or EGH-85 @760) looks like some overlap between the residential & commerical lines, then?

For the 10% piping pickup factor vs 33% factor (23% fudge factor) deabte, someone suggested using the 10% factor for interior. exposed piping since it's heating the space anyway, and using the 33% factor for exterior wall piping that loses it's heat to the cooler exterior walls in un-conditioned space. Is this one way to harmonize this difference of opinion about pickup factors?

ChrisJ

cubicacres said:

ok-that matched what WMC just told me on the tech line-the vent damper & spark ignition are included in the EG models, but not the EGH. With 780 sq ft of radiatiors, they thought either one would work (EG75 @ 770, or EGH-85 @760) looks like some overlap between the residential & commerical lines, then?

For the 10% piping pickup factor vs 33% factor (23% fudge factor) deabte, someone suggested using the 10% factor for interior. exposed piping since it's heating the space anyway, and using the 33% factor for exterior wall piping that loses it's heat to the cooler exterior walls in un-conditioned space. Is this one way to harmonize this difference of opinion about pickup factors?

My exterior piping loses about 1500 btu/h from what I calculated, I think. Having a hard time remembering. It's all insulated with 1" fiberglass.

If I use a 33% pickup factor on my system it gives me 31,000 btu/h for alleged piping losses. My piping wouldn't lose that even if was all exposed out in a snow storm. Well, ok, maybe then, but certainly not in my basement and crawlspaces.

Have you calculated roughly how much piping you have of specific sizes in your basement and other areas? If you supply us with that we can help figure out piping losses.


But, like I said before if you want to keep it simple and easy on your self try to get a boiler that falls between 20-33%. Do not exceed 33%.

The EG-65 will likely work beautifully if everything is well insulated and you carefully balance the system.
Two EG-45's setup correctly would be awesome, especially if you're using a lot of TRVs.

The EG-75 is fine.
The power burner setup is better.
The EH-85 is unacceptable.

cubicacres

Thanks-it makes sense that getting accurate measurements of the diameter & length of our connected pipes to the radiators throughout the building would change our numbers for sizing. I'm assuming they're all black steel pipe under that insulation. Anything we should be looking for as we measure the mains & return lines? Are the pipes usually the same diameter for the mains & returns, then get narrower to each radiator?

cubicacres

How would those 2 EG-45s work? Would this simulate a low/hi dual burner if one or both were firing?

ChrisJ

cubicacres said:

How would those 2 EG-45s work? Would this simulate a low/hi dual burner if one or both were firing?

Yes, though IMO it's better than a high/low burner.

The system would be setup to fire both boilers until a certain amount of pressure builds. Once that point is reached one boiler would shut down until the pressure hits a set low limit at which the second boiler would fire back up.

If a lot of TRVs are shut to keep rooms from heating one boiler may be plenty at that time. On colder nights both boilers would fire the entire time.


You'll still need to clean out both boilers after they've been installed to get all oils out of the systems and in my opinion, run water treatment to reduce corrosion. Makeup water must also be limited as much as possible and any fresh water needs to be boiled immediately.

ChrisJ

@vaporvac has dual boilers in her system. She can tell you more about how the system works.

cubicacres

What kind of controller would I use with the 2 EG45 boilers?
We don't reside in the building, but live 5 minutes away. We would prefer that it's hands-off for the tennants.

Also, can you add a condensate tank & vaporstat in a future year after the initial installation? Is there much downside to this?

Fred

cubicacres said:

What kind of controller would I use with the 2 EG45 boilers?
We don't reside in the building, but live 5 minutes away. We would prefer that it's hands-off for the tennants.

Also, can you add a condensate tank & vaporstat in a future year after the initial installation? Is there much downside to this?

You keep suggesting the condensate tank as if you really want one badly. It just isn't usually necessary unless you have some sort of return problems. It adds no valve, functional or otherwise to the system. As far as the vaporstat, I would start out with that. It is a much better alternative to a Pressuretrol as far as controlling lower steam pressures. It will be a requirement if you use a two stage gas valve or twin boilers.

cubicacres

ok. So far we've been told the condensate tank is a worthwhile investment by local contractors.

If adding one later (if ever needed) is an option, that makes more sense to us. The current block lasted 20 years and never had a condensate tank. We were hoping to get a few more years than that out of the next block, if possible.

cubicacres

Has anyone seen any value for a spirovent to reduce oxygen in the water, or a dirt seperator to reduce mineral deposits in the water? The supply house reccomends them as cheap insurance, but other contractors have said they're ineffective & a waste of money. Tempting to try if low-cost, but if really unecessary, they seem like another thing that may need servicing.

ChrisJ

The supply house selling them recommends them eh?

cubicacres

Right-single pipe steam. The oxygen will get in the condensate return water lines anyway, so spirovents won't reduce the condensate water oxygen. But is trying to reduce that initaial fill water oxygen any help over time?

And condensate water will pickup rust & debris as it moves back down the condensate return lines to the boiler. But would that initial fill water be cleaner with a dirt seperator in use?

vaporvac

Bringing your water to steam immediately after refilling with do the same thing in terms of oxygen removal.

JUGHNE

If you fill a glass container with your tap water, do you see anything in the water? If you leave the glass sit overnight would anything settle in the bottom of the glass? That is what you would be trying to strain out of the fresh water. You probably drink this water?

Condensate flows slowly back to the boiler, It might be piped down near the floor and then rise up the Hartford Loop to enter the boiler. There is some time for things to settle out in the lower piping. If the lower piping has a drip leg or clean outs, you could check the lower pipe for debris several times a season with minimal water loss to the system, if you have dry returns. If you have a lot of wet return piping, then an isolation ball valve could be added to reduce the water loss when checking the "sump piping" for debris. Eventually that water would probably clear up. Just an idea.

vaporvac

ChrisJ said:

@vaporvac has dual boilers in her system. She can tell you more about how the system works.

Oh, @ChrisJ, did you really just ask me about my system? I live for this day!
Yes, @cubicacres, i think I'm one of the only posters with a twinned system, although a few have staged or modulating burners and quite a few of the pros installed twinned boilers. I chose mine after a ridiculous amount of reading obscure publications, posting threads and reading just about ever StrictlySteam post ever written. You could probably get some good insights by reading through my threads, at least those that pertain to my system. I've asked all the good questions you're currently asking and got really great feedback from some posters who don't frequent The Wall as much as they once did. Just click on @vaporvac and find my threads ie. the discussions I've started. I

With twinned boiler you definitely need two Vstats (although I only hooked mine up a year later!) By twinning and adjusting the burner rate I was able to get an almost perfect edr fit. It is run on both temp and pressure. However, as I almost never reach a pressure to trip the Vstats, it's really a temp thing for me. The two-stage Tstat does the decision-making based on the temp differential. It starts either one or both boilers until desired temp is reached. The tstat's internal algorithm determines the differential and signals the boiler or boilers to fire. On subsequent firings only one boiler runs.
My old boiler was not as efficient and about 10% over-sized based on edr, so it's hard to credit the two boilers with ALL the savings, but i have seen a significant reduction. It only stands to reason that 230btus burns less fuel than 430btus. There are other saving due to the use of two boilers, but you can find those explantions in my posts. Be sure to read the Weil-Mcclain pdf closely. It's a brilliant (JMO!) expose on increasing efficiencies in steam systems.