Steam Heat, Weil McLain Boiler

steaming · August 2015

Hello,
I need some advise, Thank you in advance.
I have a single pipe steam system, with a Weil Mclain EG .50.PI 175 BTU boiler.
This is a well insulated masonry (brick), 3600' sq ft, three family, three story building.
There are 2 No. 40 Hoffman vertical (upright) air valves in the basement.
7 radiators on the 2nd floor with 5 Hoffman No. 40 air valves
and two maid-mist self adjusting # C 1/8 vent valves in the 2 northern most bedrooms.
There are 2 large radiator on the third floor with maid-mist self adjusting # C 1/8 vent valves and a small radiator in the 3rd floor bath room.
Boiler is raised off the floor. The return is below the boiler.
There is not enough heat getting to the third floor or often the balance is off, throughout the house, some areas warmer than others.
Any suggestions as to how to get more heat to the third floor.
thank you.
Best
Terrence
Queens NY

KC_Jones · August 2015

Have a few guesses, but really going to need more information. It would be good to post pictures of the near boiler piping for our reference to see what you are working with. It sounds like a venting issue, but there can be other factors. You most likely do not have nearly enough main venting in the basement. That being said no one can say for sure without knowing pipe size and length of your mains in the basement. The rule of thumb is 1 Gotron #2 vent for each 20' of 2" pipe. A Gotron #2 main vent flows about 26 times what that Hoffman 40 does and if they are Hoffman #40 I don't think those are main vents anyway. After you get the proper main venting then you can start getting the rads vented properly. You vent rads according to size (including pipe run out). There is a great eBook available on this site that lays out a lot of great info about venting, it's 10 bucks and goes to charity. The basic concept for the rads is to vent them faster the further away from the boiler you go. This way everything gets heat at the same time. The mains MUST be vented properly and adequately first no matter what.
http://store.heatinghelp.com/Balancing-Steam-Systems-p/300.htm

Fred · August 2015

What KC is saying is right on the money. The most likely issue is the venting, especially in the basement. Those #40 vents are really radiator vents. They are so small/slow that steam will goo to other areas (radiators) first, before the mains are cleared of air. change those main vents first and see if that resolves your problem. If you have enough head room, use Gorton #2 vents. If you don't have about 7" of head room, use Gorton #1 vents but it will take about 2 or 3 Gorton 1's to equal the capacty of a Gorton #2. You will have to build an antler to mount them on. tell us the diameter of each main and the length of each and we can tell you how many vents you will need on each main. After that is done, you will be able to start to adjust your radiator vents to balance them.

steaming · January 2016

Dear KC, Fred and the Wall:
Thank you for your reviews.
I am going to attempt to write a more concise question(s)regarding my one pipe steam system. Taking your advise I've included the attached pictures.
I have a Weil Mclean model EG-50-PI, 175 btu's natural gas steam boiler installed August 1985.
This is well insulated residential 3 story building with a 30' by 40' footprint. There are 12 radiators of varied number fins with Hoffman 40's and Maid-o-Mist air valves on 4 radiators furthest from the boiler. In the basement are two- 2" parallel mains about 30' (plus) feet which run along the east and west sides of the building.
The second and third floors are not getting steam, or the balance is wacked, some risers get hot while others are cold.
I replaced the Honeywell Pressure Limit control 20 PSI PA404A1009 and the Weil Mclean steam pressure gauge. I have thoroughly cleaned the pigtail, however the new gauge does not register. The boiler cycles on frequently, warming the first floor shutting down the thermostat. Without a gauge reading its difficult to set the Pressure Limit Control. There is no hiss of air venting in the basement. I've checked for leaks in the boiler and the floor return pipes, which checked out OK. The floor return pipes were replace 10 years ago. I have drain the boiler, but have never thoroughly washed it, for of fear of the mess.
KC, Fred and the Wall, would you kindly revisit my issues?
Thank you.
Terrence
Sunnyside, Queens, NY
Thank you.
Terrence Kehoe.

Jamie Hall · January 2016

Balance. And thermostat location. It seems likely to me -- although you can easily verify this -- that it is the thermostat which is shutting your system off before the upstairs gets heat.

The first thing to do is check and make sure that the thermostat is set properly for steam heat. If it is the type which sets cycles per hour, it should be set to 1.

Then the next thing is to veryify that it is the thermostat which is controlling; I rather suspect it is, but it's worth checking. (Just finding that the room with the thermostat is holding temperature will tell you that!)

Having done that... You need to slow the first floor down -- particularly the space with the thermostat. Way down. That means installing much slower vents in those spaces (or adjusting them, if that's possible) and putting faster vents on the upstairs radiators. You may find that you even need to turn the radiator nearest the thermostat off completely!

If some risers or areas remain cold, check and make sure that the radiator valves really are open, and that there are no sags or dips or water traps in the runouts and risers.

KC_Jones · January 2016

Also you for sure need more main venting. That little main vent you have isn't enough, unless you were standing next to the boiler when you took that vent picture. You need to measure the length and size of your mains, post that information and we can help you determine how much main venting you need. Until that is correct you can't balance the radiators in the house.

steaming · January 2016

Thank you for you help. I hope this clarifies.
The Honeywell digital thermostat is set for steam. There are 3 radiator on the first floor with Hoffman 40s.
In the basement are two- 2" parallel mains about the west is a 45' foot run and the east is 39' to the Hoffman No. 45 steam air vents

KC_Jones · January 2016

By the picture I think that main vent is actually a Hoffman 4A not 45. If that's the case you need at least 10 times more venting than you have most likely more. I would say at least a Gorton #2 or equivalent to equal a #2 per main as a starting point. Might even need to got twice that. You need to get the main venting right first that will get you in much better shape than you are right now. You are massively under vented on the mains.

steaming · January 2016

KC, thank you. It is 2 Hoffman 45, 3/4" x 1/2" Straight Steam Convector Air Valve at the end of each run. I'll start today by installing the two Gorton #2 air valves. There is 5 1/2 inches of head room for the vertical air valve. The boiler was installed in August of 1985. I've emptied the water from time to time. Is cleaning the boiler a major issue? Could that be preventing the steam?

Jamie Hall · January 2016

Cleaning the boiler is probably not an issue at all. If the LWCO is a float type, it should be blown down once in a while, but otherwise... no. Fresh water is not your friend.

steaming · January 2016

I can't find a Gorton No. 2, 3/4" x 1/2" Air Eliminator (Main Vent Valve) Should I use Gorton 14 Gorton No. 1, 3/4" x 1/2" Air Eliminator (Main Vent Valve)

KC_Jones · January 2016

The main venting is about capacity. You need to know how much capacity you need and vent accordingly. If you only have 5 1/2" of space you can't fit a #2 vent as it's 7" tall. You will need to use several #1 vents or several Hoffman #75 vents on an "antler" set up. It takes 3 #1 vents to equal the capacity of a #2 vent. With the amount of main you have I would say you need 4 or 5 #1 vents per main. If you go with Hoffman #75 probably about 2-3 of those per main. If you don't have it already I strongly suggest you get the venting book from the store on this site. It comes electronically and the money goes to charity. It's a good read and a great education on balancing a steam system.

http://store.heatinghelp.com/Balancing-Steam-Systems-p/300.htm

Fred · January 2016

The Hoffman 75's are about 5-1/2" tall if you can get it screwed into you elbow about a 1/2" so it may be a tight fit if it fits at all. Gorton #1's, on an antler, may be the better choice. As has been said, get enough main venting on first, then, as Jamie said, start to balance your radiators to allow the boiler to run long enough to get steam to the second and third floors. Where is your thermostat relative to the radiator in that room? You may start by shutting that radiator off completely and see if the second and third floors get heat.A Hoffman #40 is a slow vent. The second and third floor may need something like Hoffman 1A's that you can adjust up or down until you get all the rooms where you want them. Main Venting first though.

steaming · January 2016

Gentlemen,
I am pleased to follow your direction. The 2 Hoffman 75, 1/2" x 3/4" Straight Steam Main Air Valve was installed an is good fit!
The thermostat is in living room (16'x10'), the nearest radiator is 16 feet away under a bay window.
I replaced the Honeywell Pressure Limit control 20 PSI PA404A1009 and the Weil Mclean steam pressure gauge. I have thoroughly cleaned the pigtail, however the new gauge does not register. Will I now get a reading with the install of these new valves? It's difficult to set the pressure control without an indicator.

KC_Jones · January 2016

I doubt that is enough venting, you are going to need at least 2-3 per main total of 4-6 vents for your system at least maybe more. You don't want to see pressure in your system, pressure is bad. That being said if you are looking at a 0-30 PSI gauge it will almost never show anything. If you truly want to see what is going on you need a good low pressure gauge (0-3 PSI max) in addition to the gauge you have now.

steaming · January 2016

My goodness that's a lot of vents, this a residential home. What you say a low pressure gauge makes sense. I replaced the pressure gauge recommend by Weil Mclain, I will add (0-3 PSI max). The boiler has cycled on, no air out of the new valves.

Fred · January 2016

Yes, as KC says, at least 2 to 3 Hoffman 75's on each main. When you say no air out of them, do you mean you can't hear them? I assure you they are venting. Feel the main and see if they get hot towards the end of them. If so, air has been pushed out. I'm not sure what you mean by "It's difficult to set the pressure control without an indicator. " The scale on the front of the Pressuretrol should be set at .5PSI and the white wheel, inside the pressuretrol should be set at "1". That will give you a Cut-out Pressure of 1.5PSI. That's about as high as you want the pressure to ever get. The 0-3 PSI gauge will help you monitor that the Pressuretrol is doing its job. Even that gauge may not move until the boiler runs for a long period but that's a good thing. Low pressure is what you want.

steaming · January 2016

Fred, thank you for the detail.
Could the problem be at the boiler?
The boiler fires up frequently. I don't think it's making enough steam to push the air out. I can not hear the air escaping, is correct. The mains are hot. There are 3 radiators on the first floor. The three first floor radiators are cold, sometimes warm. Some of the risers on the first floor that lead to the second and third floor are cold. The valves at all radiators are new and working. I replaced the Honeywell Pressure Limit control 20 PSI PA404A1009 and the Weil Mclean steam pressure gauge. I have thoroughly cleaned the pigtail, however the new gauge does not move. Without a gauge reading it is difficult to set the pressure control. The pressuretrol is set at .5PSI, the white wheel is at "1".
The boiler was installed in August of 1985. Is there away to increase the volume of steam?
terrence

BobC · January 2016

Do you know what the sq ft of steam rating of the boiler is AND what the EDR (sq ft of radiation) of all the radiators is? As long as the boiler sq ft is the same or more than the radiator sq ft look elsewhere for your problem.

Even if they werre equal there is another 33% built into the boiler rating to cover any possible piping losses, it's doubtful you have that kind of piping loss.

Bob

Fred · January 2016

I don't believe you have enough main venting but let's look at another thing first. What type Thermostat do you have? If it is a programable one, it needs to be programed for steam, 1 cycle per hour. They come from the factory with a default setting for forced air, which is 5 cycles per hour and that setting does not allow the boiler to run long enough to get steam throughout the system. Also, Is your thermostat satisfied when the boiler shuts down? If so, obviously that room is getting to temp before steam can get to the rest of the system. If that's the case, shut the radiator in that room completely off and see if the rest of the radiators heat up.
I am leaning towards the thermostat not being programed for steam at 1 CPH. Check that out first.

steaming · January 2016

OMG, KC, Fred and the Wall:
What a difference the two new main vents made. Mains are now too hot for the touch! Steam/heat is now traveling up the risers.
Doing, seeing, feeling is believing. Happy, I followed your direction. The Honeywell Thermostat is programmable. It is set for heat/steam 1 and a factory default of 2 cycles per hour that can not be changed. I will build antlers, with 2 Hoffman 75 for the east main which is 2" x 30'ft and west main is 2" x 44' ft . Do you think that will be sufficient? I will then work my way up the three floors and direct my attention to each radiator valve. I better buy the venting e-book!

Steamhead · January 2016

It looks like those Hoffman #75 vents are scraping your ceiling. If you build an antler it will raise the vents higher, and you'll have to go thru the ceiling to accommodate them.

Before I'd do that, I'd drill and tap the side of the longer main for 1/8" pipe thread near where the existing vent is, and put a Gorton #C in it. Since the long main has 50% more air in it, this should increase the venting rate on that main to where the steam should reach the ends of both mains at about the same time. This will balance the system much better.

steaming · January 2016

That is an important point. The steam needs to reach the end of each main line at about the same time. If I add a Gorton # C vapor equalizing valve in the horizontal longer main (44') near the Hoffman # 75 vent, should I not add anymore vents on the 30 foot shorter main line? I'd like to avoid opening the ceiling, but if need be I'll do it.

Steamhead · January 2016

Not yet. Do things by degree. Bring your mains into balance and make sure they heat all the way to the end before the steam goes up the risers. Then add more if needed.

Fred · January 2016

@steaming , Glad you are making Progress! Follow @Steamhead 's advice. He knows what will work best!

EzzyT · January 2016

Has anyone else noticed that the second take off tee on the boiler header is reduced on one side of the runs of tee which will cause water to sit in the header then rather flow down the equalizer. @steaming That's a concern i would look into

Fred · January 2016

EzzyT said:
Has anyone else noticed that the second take off tee on the boiler header is reduced on one side of the runs of tee which will cause water to sit in the header then rather flow down the equalizer. @steaming That's a concern i would look into

Now that you mention it, the header looks like it's pitched back towards the boiler riser too. Probably because of that reducer on the equalizer end.

Steamhead · January 2016

Fortunately, there are unions around that tee, so replacing it won't be too difficult.

Abracadabra · January 2016

Need to install a 0-3 psi gauge to get a decent feel of what pressure you are making.

steaming · January 2016

Thank You All,
I added the Gorton No. C vapor equalizer on the 44 foot main run. And attaching a few photos from different angles of the boiler. I'll order a 0-3 psi gauge today.

steaming · January 2016

This is the installed Gorton No. C.

steaming · January 2016

The header has a slight pitch toward the reducing Tee. Not enough pitch for the water overcome the reducing tee. Most condensation is probably returning down the boiler riser. What is the benefit of replacing the reducing tee with say a 3" tee a close nipple and reducing elbo. The main are not insulated. They were once wrapped in asbestos tube insulation and long ago abated. Gentlemen, I sincerely appreciate all your time and advise. I hope I am not over extending my inquiries.
Terrence
Sunnyside, Queens, NY

Jamie Hall · January 2016

The first thing to do is to reinsulate all the mains. It's not hard to do; there is snap-on fiberglass insulation available from a number of sites. 1" is a good thickness.

Steam Heat, Weil McLain Boiler

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