Commercial Building help please

Hootie · November 12

First, thank you for reading this mess and commenting. I am a high-pressure boiler/turbine guy who kind of happened into this world this year after my career was displaced. This community and the books have been a blessing.

I’m managing operations and maintenance for a historical commercial building built in the 1930’s. It has one-pipe steam heat on 3 floors (basement rads in ceilings), and a heat exchanger (terminology help please) in the attic that cycles the building air through a coil. I have no current 2nd floor tenants, so radiant heating on that floor is not a priority other than preventative maintenance.

The building diesel usage history felt crazy high to me (23+ GPD), so I bought a couple of Dan’s books, and started with tracing steam lines looking for vents. Aside from the (4) F&T traps, there were none. Well, there were (2) Hoffman 79 Hot water vents installed at the end of the basement/1st floor mains where the 1931 blueprints called for “Air Vents”. Based on their location, I assume the vents kept spitting and dying until someone put a backwards vent on it and no more spitting. I cannot change the vent locations, so I was thinking, a big mouth for each line plus whatever needed to trim out the required venting. Advice on this would be very helpful. Pics are included. They’re both in the boiler room above floor drains, I do not care if they spit or whistle.

All Rads have Hoffman 1A vents, and all seem to be working now. According to the tenant, they would spit and leak all the time before I got here. The paint on the near-boiler radiators is all peeled away as well, while all the 2nd floor rads are fine.

The pressuretrol was turned way up when I got here (5psi). I cleaned out the pigtail, and set the ptrol to around .5 cut in, 1 diff. I have no idea if this thing is working. It seems to just run to satisfy the thermostat.

The thermostat is an old Honeywell mercury dial. Reliable for sure, but it’s located 12 ft from the boiler with no other readings throughout the building or exterior. This building is vacant evenings and weekends. Should I update this to a programmable unit, and which one?

The attic air handler is its own can of worms for a later date, but I drilled and welded on a 1/2” nipple earlier this season and added two Gorton no 2 vents, though I moved one of them to a basement main to help with venting temporarily. I plan on adding a gorton D on the inlet of the unit to vent that last few feet as quickly as possible. The traps on the unit seem to work.

I currently have the boiler set to a low flame. It was set to full flame when I got here, but with the lack of vents, it was going nowhere. Once I get my mains properly vented, should I try to go back to a full flame? I’ve included the boiler specs and rad sizes, main runs, below.

Boiler: Weil McLain 1086 , Carlin 701 CRD Burner, unsure on current nozzles

Main runs

Basement A: 180lf @ 2"

Basement B 232 @ 2"

2nd Floor 368lf @ 2" (guess. lines in floor fill.)

avg Radiator size 29x32 (27 standing units plus 10 ceiling/wall units)

I used Gill and Pajek's Capacity Chart to come up with a plan for venting roughly 17cfm @ 3oz from the mains. (4.14 Loop A, 5.34 Loop B, 8.46 Upper loop)

Again, I really appreciate the feedback. This building is a real gem in my town and I want to keep it open for many years to come.

Jamie Hall · November 12

Looks and sounds like you are headed in the right direction, anyway.

To get some kind of handle on fuel usage, how big is this place? (heated square feet). Insulated? And where are you located (what climate). And was that 23 gallons per day kind of a peak figure, or an average? Reason I ask is that that may not be unreasonable in some climates for some buildings. Sorry…

Hootie · November 12

https://forum.heatinghelp.com/discussion/comment/1872079#Comment_1872079

Thank you, I think it's about 13k sq ft total. Stone and masonry siding with thick walls, but single-pane windows throughout. Washington State, so mildly cold climate. My fuel figures are all averaged monthly based on the first and last working day of the month: (Start total+deliveries-end total)/Number of days.

Jamie Hall · November 13

I'm sorry to say this, but unless by Washington State you mean well west of the Cascades that usage may not be that bad for an uninsulated building that size. Now you may well be able to improve on that some — but your biggest bang for the buck is going to be to ensure that you have gotten after as much of the air leakage as you can. I'm not suggesting replacing the windows — just make sure that the frames are sealed to the wall openings and that the windows really do close reasonably tight. You can also consider storm windows.

EBEBRATT-Ed · November 13

The pigtail and the piping under the pressure controls looks to be black steel which can plug up. I would urge you to replace all those fitting with brass and make sure the pressure controls actually kill the burner on high pressure.

Actuall you should have 3 pressure controls on that boiler.

1 operating control

1 high limit control (backs up the operating control)

1 control to operate the burner on lo-high fire………or do you switch that manually??

I would recommend using the existing. high limit control for lo-high fire and installing a new manual reset high limit control for the burner. You will have to run 2 new wires from the lo-high fire control to the burner. If you take the junction box cover off the burner you will find 2 yellow? I think wires wire nutted together. Hooking those to the new control will give you automatic lo-hi fire

Honeywell L4079B1033 is the manual reset control needed.

The air handler in the attic is steam.

Looks like an older job that was well taken care of at one time.

dabrakeman · November 13

On your mains I would suggest at least 2, 3 and 4 Gorton 2's respectively on the A, B and 2nd floor mains.

Hootie · November 13

https://forum.heatinghelp.com/discussion/comment/1872094#Comment_1872094

Yeah, west. all the way west. 3-4 snow days a year.

Hootie · November 13

https://forum.heatinghelp.com/discussion/comment/1872127#Comment_1872127

with that model of manual reset, will I have to manually press it if it goes beyond the set pressure limit? I worry about an unattended building in the winter on the weekends. Then again, I should probably be much more worried about the boiler.

mattmia2 · November 13

You will have 3 controls, one that sets the threshold between low and high fire, one that turns the burner off altogether, and a 3rd with a setpoint higher than the operating controls that is manual rest so if the operating control fails and trips manual reset control, you know that you have to fix the operating control. The manual rest control won't trip unless something has gone wrong. Ideally the manual reset control would be on a separate tapping and water seal.

EBEBRATT-Ed · November 13

@Hootie manual reset is required on larger boilers now. It may not have been when this was installed.

Your operating control is you upper steam limit to shut the burner down on steam pressure.

The High limit only come into play if the operating control fails or the pigtail becomes plugged. You can set the HL up to 10psi or so.

Your burner I think has lo-hi fire but no pressure control to operate that. I think you only have a manual switch on the burner Junction Box.

Correct me if I am wrong.

My thought was to kill two birds with one stone. Use the existing HL as a Hi-lo fire control and put a new HL (Man reset) on to upgrade the controls. Then when the burner fires it will run on low fire and only go to high fire if it can't maintain steam pressure on low fire.

Hootie · November 14

https://forum.heatinghelp.com/discussion/comment/1872221#Comment_1872221

I love this idea, and I appreciate the feedback. I put in a quote from Grainger for that manual reset, also a new PA404A Ptrol and separate pigtails, as well as a 0-5 psi gauge. I'm hoping one of the old 404 units is still salvageable for the Hi-lo, because that would be ideal.

EBEBRATT-Ed · November 14

@Hootie Run 2 wires (line voltage) from the lo-hi fire pressure control to the burner junction box. Put the pressure control in series with the toggle switch. If either the control or the switch is open the burner stays on low fire.

If you keep the switch open (low fire) the burner will only run in low fire. If you want auto lo-high fire turn the switch to on (up)

Hootie · November 14

@EBEBRATT-Ed look what I found in the file cabinet! Good call 😁

Thank you again.

clammy · November 15

Being you have just started on taking care of the system here s a few things i would check aside from main and radiator vents .

What is the condition of the boilers heat exchanger . Is there any record of when the last time the flue passage clean out plates have been removed and the section brushed clean and the burner removed and combustion chamber been vacuumed out ? Has anyone performed a combustion testing on the burner and made sure that it some where within the proper combustion numbers? Checked pump pressure and air diffuser on the burner aside from burners blower wheel ? What is the stack temperature high stack temps waste fuel and can be caused by dirty fuel passages .improper burner setting ,lack of barometric draft which increases flue temperatures and retards the heat exchanger from absorbing heat and sends it up the stack .When i have been faced with unknown service history of older boilers i usually like to see how much mud has build up in the boilers water side . Many see zero merit in doing so but over the years a simple draining and wanding of the water side of the boiler usually yield good result being steam boiler like creating steam from water not mud which tends to really build up in the water side push nipples . Muddy water requires more btus to boiler the water out of the mud . Some of my best result on older system performance wise has been flushing and wanding the bottom of the boiler . the second biggest improvement for performance is insulation of steam mains and then the one most dislike the most up dating and replacing main and radiator vents . If radiator vents are spitting there either done and need to be replaced or you have issue w the quality of steam the boiler is producing which id usually related to mis piped boiler.dirty boiler.wrong water level being maintained in the boiler to high or to low a water level and or mud build up in the boiler . A flushing of wet return is usually in order every 100 years or so also lol

I would thing that a building that size would use about that per day from dealing w homes about that size that where firing bout 18 gph and they went through a lot of oil alot . As my dad used to say big building big bills . As for thermostats possibly try using a t stat that allows you to use a remote wireless sensor and or possibly a temperature averaging style thermostat they are also available using wireless sensors great for older homes and building no wires to be ranand the stat can be powered and mounted in the mechanical room and most allow internet connections for remote monitoring.

If you really want to get the boilers firing rate correct do a edr on the existing connective load and go from there in sizing the correct nozzle for the boiler . with a hi fire low fire burner you should be able to get it within the proper firing rate as long as its not grossly underfired .

a small note and a personal peev if the main and radiator vents are over 10 years old just replace them they have earned a retirement they do alot of work and nobody ever realizes it so they usually earned a retirement .

peace and good luck clammy

Commercial Building help please

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