Is Main Vent (Vent-rite 75) large enough on this one pipe system?

Jack M

I don't have a lot of experience, but I do know from the 10 years of running this system (and paying those oil bills) that as I drop the water levels down (it slowly drops as I flush the low water cutoff once a week) that the system seems to run better. I sometimes will leave it running 2-3 inches below the full water mark and I get steam to the radiators quicker. Does that mean anything?

nicholas bonham-carter

How long does it take, and are you using a temperature setback?
You can look in the boiler manual, and find out at what height the waterline should be. Maybe if your low water cut off had been installed at the wrong height, the waterline has been too high.--NBC

Fred

What brand and model boiler? Steam boilers should only be filled somewhere between 1/2 to 3/4 of the way up the sight glass, depending on the make and model. The rest of that space in the boiler block is called a steam chest and is required to provide sufficient steam to the header and mains.

Steamhead

Jack M said:

I don't have a lot of experience, but I do know from the 10 years of running this system (and paying those oil bills) that as I drop the water levels down (it slowly drops as I flush the low water cutoff once a week) that the system seems to run better. I sometimes will leave it running 2-3 inches below the full water mark and I get steam to the radiators quicker. Does that mean anything?

It might, if the boiler is not piped correctly. See if you can get a picture of the steam piping as it leaves the boiler and goes up into the mains. In particular, we would want to know if there is a hexagonal reducing bushing screwed into the boiler's steam outlet before the steam pipe screws in.

Jack M

Fred said:

What brand and model boiler? Steam boilers should only be filled somewhere between 1/2 to 3/4 of the way up the sight glass, depending on the make and model. The rest of that space in the boiler block is called a steam chest and is required to provide sufficient steam to the header and mains.

This would explain a lot. The boiler has a "water line" mark on the outside. However the service guy always fills the boiler to a black line marked on the copper tube adjacent to the sight glass. He told me the "water line" marking on the boiler was the minimum (the lowest level) the boiler water should drop to.

So I just drained the water level down just below the water level. (almost even). With the boiler water level dropped down this low the pressuretrol is now above or almost even with the wter line. Not sure if this make a difference. I will fire it up again and time things.

Fred

The yellow line with the question mark on it is the highest I would go but thee yellow line across the sight glass is acceptable also.
The Pressuretrol is still too low for either of those water levels and you should get a vertical pigtail (looped pipe) or add a nipple to raise it higher. Also, that McDonnell Miller #67 Low water Cut-off tapping that the pigtail is now mounteed on gets plugged up very easily and frequently so you will want to clean the pigtail and that opening at least twice a heating season (I know from experience. I finally moved mine to the boiler tapping where the 0-30 pressure gauge is mounted, using a pigtail and a Tee to mount both. You can then put a 1'4" plug in the LWCO tapping.
The other thing you should know (not obvious to most homeowners) is that the TOP line (set of grooves) on that LWCO is the level at which the Low water Cut-off will trip on low water. Most people just think that is a decorative design in the casting.

Jack M

Regarding the boiler hookups and a possible reducer......
Yes, the boiler has a 3" x 2" reducer (ward) on the boiler hookup.
There are two attachment places for a pipe on the back. One of these is above the water line (the one in use) and the other is below the water line.
The attachment location up above the water line has a 2
1/4" black pipe attached (outside diameter). The flange attaching this pipe to the boiler reads "WARD 3 x 2."
The steel boiler itself sits on cinder blocks up off the floor. The previous boiler was removed more than 40 years ago. More than 1/2 of the radiators in the house were removed about that same time.

Abracadabra

I'm not 100% sure, but I don't think I see a header or equalizer or hartford loop. Can you take more pictures from the front and left of the boiler?

Jack M

Abracadabra said:

I'm not 100% sure, but I don't think I see a header or equalizer or hartford loop. Can you take more pictures from the front and left of the boiler?

Is this the Hartford loop?

Abracadabra

No Header.
No Equalizer.
No Hartford Loop.

The boiler is not piped correctly.

Jack M

why was a reducer installed (3" -2")? Is there a reason the boiler was elevated on the cement blocks? I do religiously flush the LWCO (guess that's a good thing).

Abracadabra

Because the knucklehead that installed it didn't have the tools to thread 3" pipe?

Sometimes code requires a pad, keeps the boiler up from moisture in a basement floor, if the area has a tendency to flood it's a good idea to raise the boiler to prevent damage to it. I don't like using concrete blocks unless it's an emergency install, and if I do use them, I'll use the solid blocks, not the hollow ones.

Jack M

Does any of this explain why the boiler pressure gauge always reads 10 psi? ( I realize the gauge's accuracy is in question and I need to figure out how to install a second gauge with pigtail).
When the vents are removed from a few radiators on the first floor I can feel the cool air flowing out of the radiators, however if the system was indeed running at 10 psi, shouldn't the I see that air exiting the radiator with determination, force, or exuberance (with the vent removed)? I do recall reading something in Dan's book about overcompensating for a flawed "near boiler" design by relying on extra pressure (and higher heating bills).

Fred

The near boiler piping is a mess Jack M. I don't know how old the boiler is but you definately want to get that right when the next boiler goes in or sooner if possible. If you have the owner's manual, look at the installation diagrams and you will see how it should have been installed.

Jack M

This put me in a quandary. Should the oil fired boiler be pulled/replaced and the near boiler piping be re-plumbed (saving the old radiators) or is it time to switched to natural gas condensing boiler and radiant floors/ wall panels?
I like the simplicity of the steam heat and the comfort. A condensing boiler is going to set me back $$$. I'll be paying to run circulating pumps all the time. The condensing boiler would free up the flue to run a wood or coal stove for backup (provided I'm home to light the fire). Would the high efficiency condensing boiler and wall panels be as comfortable in New England? No one ever complains about the quality of the steam heat in this 1920's farmhouse (though I do complain about the oil bills).

Fred

If it were me, and you have natural gas available to you, I'd put a gas boiler in, keep the radiators and make sure the new boiler is sized correctly for the radiator EDR and that the new boiler is (at a minimum) installed like the installation manual advises. Converting from oil to gas is where your saavings will occur. you likely will need to factor in a chimney liner as well but that will still be considerably less than ripping out all the rdiators, installing radiant panels etc.

Jack M

I like the steam heat. This house has a lot of orignal character and the steam contributes significantly to that feel. During the winter months when the boiler is running a lot, steam seems to hold its own in terms of efficiency. However in late spring and early fall there's only a short call for heat during the morning and evening. Can steam run efficiently in these "shoulder seasons?" I ask only because I guess I can't use my poorly designed system as a model or good example. In late spring my system still takes the better part of an hour to build up the 10 psi needed to get steam to the radiators.

Jack M

Fred said:

Converting from oil to gas is where your saavings will occur. you likely will need to factor in a chimney liner as well but that will still be considerably less than ripping out all the rdiators, installing radiant panels etc.

I know we don't talk price on the Wall. Will the utility rebates the cost a condensing boiler is less than a standard iron steam boiler. The venting on a condensing boiler is a cheap piece of pipe vs re-lining the chimney. I have no idea what it would cost to install all the black iron pipe the correct way. Pex is cheap but not so much for radiant wall panels.

I see that some steam boiler companies sell all the "near boiler" piping in a kit. Is there any way I could find out how my boiler was supposed to be hooked up? The right way?
"Crown UPCS 4 Boiler (steel boiler) rated at 315 square feet of steam, 75,000 btu hot water, running on a 1gallon per hour Becket RWB burner (like a Beckett AFG). The tag on the boiler says “15 PSI” steam.

Abracadabra

Jack M said:

Does any of this explain why the boiler pressure gauge always reads 10 psi? ( I realize the gauge's accuracy is in question and I need to figure out how to install a second gauge with pigtail).

I doubt your boiler is running at 10PSI, but without a functioning gauge it is impossible to tell and worthless to guess.

Fred

The Empire State Building runs on 2 PSI of pressure and most of us on this site run on anywhere from 2 ounces to 1.5PSI. I personally have a boiler rated at 866 sq.ft. of steam and I typically run at 2 ounces on a normal heat cycle. On the coldest of days (sub zero) I get up to 8 ounces on a few cycles. If your boiler were piped correctly and the mains were vented to the capacity needed, you could easily run at those pressures. At 10 PSI, your system is just throwing dollars in the aair. The higher the pressure, the slower steam moves.
Look at this Crown boiler schematic. It shows the basic near boiler piping diagram, with a Header and the risers to the Mains tie off of item #6 on the schematic. One Tee on the header for each main.
http://www.crownboiler.com/documents/Bermuda_Near_Boiler_Piping_Schematics.pdf
Near boiler pipe kits are sold by Crown, Burnham and Weil Mclain that I know of and I think probably most boiler manufacturers or distributors sell them.

Jack M

Searching the web, these boiler kits are not at all costly. I have a hard time understanding how someone would skip doing this. If my boiler were down off that tower of cinder blocks, this piping would fit.

Fred

I'm not sure why they put your boiler up so high. Do you have a history of your basement flooding? If not you can certainly lower it. That may mean dropping the wet return to be sure it is below the normal water line but tht looks like it would be just adding a littlee pipe to the bottom of that vertical (that your vents are on top of) and carrying the horizontal around, closer to the floor and tying it into the pipe at the bottom of the Hartford loop, in the picture above.
EDIT: Keep in mind if you order a kit, you will want an extra Tee in the header for each Main you have. It looks like you may have 2 or three Mains, hard to tell from the picture.

KC_Jones

They might have raised it because of the water line of the old boiler. I am guessing that boiler isn't original so perhaps this replacement had a much lower water line so they raised it way up to match that. Still seem excessive to me, but wouldn't be the first time this has been done.

Fred

Would have been a lot better to have lowered that vertical return about 12 to 18 inches and then carry that little bit of wet return around. who knows what they were thinking. They certainly didn't use their heads on the piping.
EDIT: I kind of think they thought they had to match the actual physical heigth of the old boiler???

Jack M

Am I correct in assuming that the only way to change "near boiler" piping is to remove everything? The first pipe threads onto the boiler, the second pipe threads onto the first pipe, the third pipe threads onto the second, and so on. There's no changing anything unless everything ( all the way to the radiator) comes out.

SWEI

Somewhere in that chain should be a union. If not, you install some -- typically near the boiler to allow for future replacement.

Fred

Jack M said:

Am I correct in assuming that the only way to change "near boiler" piping is to remove everything? The first pipe threads onto the boiler, the second pipe threads onto the first pipe, the third pipe threads onto the second, and so on. There's no changing anything unless everything ( all the way to the radiator) comes out.

If the riser coming out of the boiler is the right size (same size as the boiler tapping) and the length of it works in the new configuration, and you can get the pipes attached above it off without damaging the riser, you can leave that in the boiler and build from there. Even if that riser is short, you can add a union there and add to it. From your pictures, you will have to rebuild the rest of it.

Abracadabra

Jack M said:

Am I correct in assuming that the only way to change "near boiler" piping is to remove everything? The first pipe threads onto the boiler, the second pipe threads onto the first pipe, the third pipe threads onto the second, and so on. There's no changing anything unless everything ( all the way to the radiator) comes out.

No.. you don't need to remove everything all the way to the radiator. Judicious use of unions and possibly welding will allow you to replace only what is necessary. Having said that, I wouldn't waste my time replacing the near boiler piping on the boiler. The boiler looks like it's at between 20-25 years old. By spending any amount of money redoing the near boiler piping on that boiler, you are taking a bet that the boiler (having been piped into your system the way it is for 20-25 years) will have a significant amount of years left. I wouldn't take that bet. If you are truly interested in saving money long term, replace the boiler with a more efficient model and redo the near boiler piping. In the end, your only real additional out-of-pocket will be the material cost for the boiler.

JMHO

Jack M

Are there boilers that are held in high regard here on the Wall? My boiler says "rated at 315 square feet of steam" but I'd like to do the numbers (EDR). The good news (need some good news) is that existing radiators are capable of keeping the house warm on the coldest days in winter.

Fred

Read throught this current tread for opinions: http://forum.heatinghelp.com/discussion/154100/which-brand-and-model-of-steam-boiler-is-the-most-reliable#latest

Jack M

Installed a second pressure gauge (low pressure) where the pressuretrol attaches. I removed the pressuretrol and installed a new pigtail and a gauge valve and then attached the new gauge. The plumbing supply house gave me the only low pressure gauge they had (said it was for steam) however this is a 0-15 psi gauge.
I fired up the boiler. The old gauge on the front of the boiler (0-30 psi) climbed to 5 psi, then 10, and at 35 minutes in was reading 13 psi. The new gauge mounted on the pigtail never moved. The pigtail was hot on the lower part but only mildly warm on the upper part. Was this "new gauge" installed correctly?
The height of the new pressure gauge is just above the sight glass. I know that the new gauge works to some degree because when I screwed it onto the gauge valve it (the gauge) registered a small amount of pressure until I remembered to turn the valve to "open." I'm not getting any pressure reading from over top the LWCO.

Fred

A 0 - 15 PSI gauge isn't much better than the 0 _ 30PSI gauge but at least it seems to suggest the old gauge is faulty.
From the picture, it looks like the needle on the new gauge is under the stop pin. Is that just the angle of the picture? (I hope).
If you are sure the valve you installed under the new gauge is open, then you can rest assurred the old gauge was misleading you.
With that new gauge, you probably won't see any pressure on the gauge. It takes a 0 - 3PSI gauge to see pressure in ounces and even then it will be 2 Ounces to maybe 1 PSI.
Did we not give you the site/gauge we typically use? here it is again: http://www.valworx.com/product/low-pressure-gauge-25-0-3-psi

KC_Jones

Finding an actual low pressure gauge at a local supply house is virtually impossible. When I was doing mine I specifically asked for a 0-15 OUNCE gauge and they quoted me a 0-30 PSI gauge. I asked them why and they said well we don't understand what you are asking for and why do you need one that low? That along with a huge list of other reasons is why they didn't get my business. Go to the link Fred showed, you want a gauge that reads no higher than 3 PSI. I have a 0-15 ounce gauge on mine and the highest I have seen it is 1 1/2 ounces when it was 0 degrees and blowing 25 outside and my system was running almost constantly. I also agree with Fred the old gauge is toast.

Jack M

I cleaned out the pressuretrol. The inside of the plunger style diaphragm that pushes up into mercury switch was fill will debris (similar to the old siphon pigtail)
Can the pressuretrol be tested? The fasteners on the base of the old pressuretrol were extremely worn showing signs of repeated use. Leaves me to believe that someone had been removing the plunger style diaphragm on a regular basis for many many years.
If I find a way to test the pressuretrol and it should be in poor condition should it be replaced with a vaporstat instead?

BobC

It sounds like that ptrol is mounted too low, see if you can put a six inch 1/4" pipe nipple under it to get above the crud.

If you do have to replace it, using a vstat will depend on what kind of steam system it is. i did replace the pstat on my old Burnham with a new vstat (the pstat had died) and ran it under a pound, the system ran quieter and I saved some fuel to boot.

Bob

Fred

I think I'd still put a 0 -3PSI gauge on the boiler first and see where the pressure is for sure. If the Pressuretrol looks at all like it is questionable, I would replace it. If you go with a Vaporstat, it can be used with a new boiler, if you make that decision.

Jack M

I've been really encouraged by the system's performance with the boiler's lower water level. This one pipe system has never consumed much water (just replacing what I loose when flushing the LWCO). Time to start learning what I can and not leaving everything up to someone else. I realize now that I've been relying on the thermostat to shut the system down and between that and overfilled boiler I have fallen short of peak performance from this old system. If I could get the system running so that the boiler would shut off when the radiators are full (instead of running until the thermostat is satisfied) I could reduce the run time of the burner considerably. With the corrected water level those radiators filled quickly with the 20 year old vents removed. I have some adjustable "maid-o-mist" vents ordered to see if I can fine tune the venting ( also hook up a low pressure gauge). Is there a way to trigger the LWCO without draining all that nice old water from the boiler. Can I isolate the LWCO while the boiler is firing and make sure the LWCO stops the burner (like it should)? With no Hartford loop I would sleep better. (they are supposed to test it each year during the service cleaning).

Fred

The way to test a McDonnel miller #67 LWCO (which I think is what you have) is to open the blowdown valve on the bottom of it while the boiler is running. The boiler burner should shut down with a matter of seconds after opening the valve and when you close the valve, the burner should kick back on.
EDIT: Be careful, the water will be HOT!

Jack M

Won't I loose a ton of boiler water if I let the LWCO just flow out the bottom through the blowdown valve? I'll have to drop a lot of water before I get down to the shutoff line on the LWCO. Then I'll have to add that same huge amount of (oxygen laden) water back into the system. Is there a shutoff from the boiler that would just let the LWCO drain without draining the boiler?

vaporvac

I basically tested mine during the weekly or so blow-down to flush out crudge. i thought that was the goal: cleaning and testing. Then be sure to fire back up. Good that the maintenance people do that, but it's really a more frequent job with the float type. the probe type just needs a once yearly check and cleaning with no weekly blowdown.