Joined on November 24, 2007
Last Post on April 23, 2014
@ March 8, 2014 9:56 PM in Stage-fired boiler controls?I'm so glad to hear your report of good operation, even though you have to flip switches to get some heat.
Now that the boilers and burners are operational, with 2 different burn rates, I wonder how important the Taco boiler switcher is. It would be better to log the results further to see which one should be the lead boiler, and which the lag.
As I see the control strategy, when firing from cold with a two-stage thermostat, the thermostat will energize both boilers. As they fire, and the steam fills the system, the vaporstat will cut off the lag boiler at the setting you choose-from 2 ounces to 6, (if the pressure should rise that high). As the inside temperature has risen by this time, the 2-stage thermostat will probably reduce firing to 1-stage(boiler), and the lead boiler will carry the load.
During most of the winter, the temperatures are average, instead of very cold like the design temperature. Maybe these average winter temperatures can be handled by the smaller 200k boiler, and if so, that would be the lead, which will continue firing when the lag has been cut off by the 2nd stage of the thermostat, or the vaporstat.
In a vacuum system, at moderate cold temperatures, the vaporstat will rarely see the 2-6ounces of maximum pressure, so it will be up to the thermostat to do most of the controlling of the 2 boilers, while operating so much of the time at sub atmospheric pressures. Some experimental time will be needed to determine the correct setting of the CPH on the thermostat.
I'll probably be doing the same thing with my chapel Dunham project this summer, and so any observations you may have will be useful.
Keep up the good work--you are a great credit to all of us non-professionals on this site!!--NBC
@ March 6, 2014 10:57 PM in Need Help - New Gas Boiler for Steam System ProblemsHow did you find the installer?
If you have to take him to court, I am sure you can have someone here write up a description of what was done wrong, but let's get to the bottom of the problem first-take those pictures, with the naked pipes exposed.--NBC
@ March 6, 2014 10:35 PM in Steam traps?State supply.com would be one source. You could check Ebay for other peoples non-functional throwaways for the best price.--NBC
@ March 6, 2014 7:35 PM in Opportunity KnocksUS boiler DBA Burnham Boiler co. need some help writing an explanation for their refusal to certify their Megasteam boiler for use with a gas burner.
Good luck with your endeavors!!--NBC
@ March 6, 2014 5:46 PM in Replacing stuck Main Vents on the dry returnsAfter using PB blaster or Kroil, use an open end wrench for a good fit. Apply pressure to it, while whacking the wrench with a hammer. This should get that bushing out. An impact wrench might work as well, if you have the clearance needed.--NBC
@ March 6, 2014 5:40 PM in Boiler replacement?You could break the union between the boiler and the first elbow, and then that would be your larger pipe size horizontal header. Use two risers to come up, and drop back down into this header, both on one side of the vertical takeoff. Then connect the equalizer to the other side.
A big pipe wrench may enable you to reuse some of the old piping. Supply pipe is usually in pretty good condition.--NBC
@ March 6, 2014 5:34 PM in Atmospheric boilersWhat about putting some stainless steel sheets under the burner area to reflect back the heat?
As far as piping in combustion air, I would be a little afraid of a freeze up when the boiler was off for a period of time. Maybe bring the combustion air closer to the flame would help.
Alternatively, we Midwesterners will have to buy and learn how to use an analyzer. Using a power burner has the advantage of dialing in the burn rate to match the system more exactly I would think.--NBC
@ March 6, 2014 5:24 PM in Salvage Cast Iron Radiators773-407-7115--seems to be a business
@ March 6, 2014 3:45 PM in Completed boiler & chiller instalHot water supply
Hot water return
Cold water supply
Cold water return
Hot air (politicians floor)
Hopefully the south side chillers were pumping their heat into the north side--NBC
@ March 6, 2014 10:32 AM in System pipingMaybe 2 smaller boilers would be easier to man oeuvre, than one larger.-NBC
@ March 6, 2014 10:18 AM in Beating a dead horse.Since there seems to be a general trend to switch, rather than fight, more manufacturers will see the necessity of certifying their boilers for gas guns.--NBC
@ March 6, 2014 10:09 AM in HELP with new steam boilerThis would be a great application for a burner on the new boiler with an adjustable firing rate to match the present EDR all the way up to later increase in radiators etc.
I don't have any oil experience, as I only have a gas atmospheric, with more limited possibilities for adjusting the firing.--NBC
@ March 6, 2014 9:59 AM in System pipingDo I understand that the dry return gradually slopes down, until, at the waterline height, it becomes wet?
It would be better to have a definite change, with a vertical drop from dry, to wet.
The reason for this is, as the pressure rises in the boiler, the waterline in the wet returns is pushed up to a new level. This rise in height will be 1.75 inches, for every OUNCE of pressure. This means more water will have left the boiler to temporarily fill up a longer length of pipe (think hypotenuse length, instead of vertical length). A situation like this can cause a very unsteady waterline, with shortened life.
Definitely readjust the slope of the supplies so they start high, and slope steadily downward to the final vertical drop. Piping as a drop header is better for drying out the steam, as well as making the final connections from boiler to header (for the novice). In addition, the drop header will trap any oils which have not been able to be skimmed off, and at least keep them from interfering with the boiling. A tee on the equalizer at just below waterline height wit a ball valve will enable draining off this oily residue.
Make sure that any wet returns are well below the waterline, by raising the new boiler, or lowering the returns.
Get a 0-3 psi gauge so you know when to stop adding main vents to the dry return. If you size the boiler right, you probably will not be building too much pressure except when it is really cold out.
A wet-base boiler with a burner whose firing rate can be adjusted would enable you to dial in the firing rate to accommodate any changes in radiation EDR (extra rads later etc.)--NBC
@ March 5, 2014 11:01 PM in steam pressure constantly releasing?If the Pressure release valve is opening, then that is a life safety problem. It is because of excessive pressure. This situation is probably a result of a malfunctioning pressuretrol/pigtail, and should be corrected immediately!!!!!!!!!!!!
If the main vent is making a lot of noise, then it is only a question of money, rather than personal safety, so you can choose when you want to burn less fuel anytime. A noisy vent on a radiator, or a main vent which is noisy indicates a need for some maintenance. You may have been paying extra to push the air out of the system, instead of allowing it to escape with no resistance.--NBC
@ March 5, 2014 7:54 PM in Boiler replacement?It sounds like the end.
Start measuring the radiators for correct sizing of the replacement boiler, and make sure the installer knows how to read the instruction manual for piping diameters, and layout. Maybe that should be in the contract.--NBC
@ March 4, 2014 11:32 AM in Carlin Gas Conversion or new oil tank?Damned if you do, and damned if you don't .
If you switch to gas at a higher cost than replacing the tank, you probably won't save enough in three years to pay for it. If you fix the tank, the prospective buyers in the future will try to get a discount as you are burning an inconvenient fuel.
Try the find a contractor button at the top for one of the experts here as opposed to someone from the yellow pages.
Don't be mislead by boiler efficiency figures, as it is system efficiency which is more important, aided by good main venting, low pressure, and correct boiler piping.--NBC
@ March 4, 2014 11:04 AM in Venting QuestionThis fills all the mains with steam first(because of lower resistance to the escaping air).
After the mains have all filled, the steam can then overcome the slightly higher resistance of the rad vents to flow into the rads--filling all simultaneously.
If you had no main vents, and large radiator vents, then the radiator closest to the boiler, in pipe feet would get steam first, and the radiators would fill sequentially in order of their distance. Before the last one had filled, the thermostat may have been satisfied, and the last rooms would still be cold.
This really a matter of balancing the resistance of the vents to the escaping air. A 0-3 psi gauge should show a back pressure of 2 ounces if you have enough main venting. When the main vents close, the pressure will rise, as the rad vents are more restricted. Air will leave each radiator at the same rate, ensuring simultaneous steam arrival.--NBC
@ March 4, 2014 5:50 AM in copper in 2 pipe steamCopper piping on the supplies is considered to be a liability, mainly because of the effects of the greater expansion and contraction of copper versus steel. These forces can cause the soldered joints to yield, or can sometimes put enough force on the sections of the boiler to force them out of alignment.
On the wet returns, the temperature fluctuations are not so extreme, and there is only one point of connection to the boiler, so the non rusting qualities of copper are a plus.
With regard to the main sucking air, is this from a main vent somewhere on the return? Generally, on 2-pipe systems, the air is vented from one location, which may have had a vacuum check valve to enable the system to run at sub-atmospheric pressures in the days of coal-fired boilers. Opinion is now devided as to the benefits/disadvantages/strategies of running a modern gas-fired boiler in a vacuum, but some are trying it.
Whether vacuumized or not, the system at the start of firing after a period of activity must push out the air before the steam can arrive at the radiators. Large main vents on that central venting point let the air escape with no resistance (back-pressure 1-2 ounces). A good low pressure gauge of 0-3 psi will show you what is happening. The advantage of the sub-atmospheric system operation is less air to push out each time the boiler fires. For best results, the vacuum should be equally distributed throughout the system.
Some pictures of the boiler piping, and of the radiator supply/return/traps/etc would help to identify the system, and develop strategies for it's continuing economy, quietness, and comfort.--NBC
@ March 4, 2014 4:43 AM in Gorton #C steam vent valve replacement + hammering/clanging noiseIf the change of vent is the cause,I would have thought that the hammering would have started as soon as you had changed the vent, instead of 3 weeks later, if you can wear a sweater, put a plug in the vent tapping, and see if the hammering is lessened.
Either one of your neighbors has made some change in his radiator, or the system pressure has changed.
See who else in the building may have noticed some hammering, and go from there.--NBC
@ March 3, 2014 10:48 PM in Help me ballance my 1 pipe steam Please!In the spring it may be time to get the Baltimore guy over again, and have him do what needs to be done.
Since you did not take advantage of all that he could offer, during his visit, you have not only been suffering the inefficiencies, and discomforts of an apparently improper installation, but also the higher cost of oil per therm.--NBC
@ March 3, 2014 10:37 PM in Leaking curved steam radiatorsWhat a beauty! No wonder you want to save it.
I think the push nipple radiators had a threaded rod or even two to hold the sections together, but with a curved radiator, probably the only force holding the sections together would be the threads of a LH/RH threaded nipple.
As far as the pressure of your interesting system goes, 1psi might be tops, and maybe 2 ounces would be better, as it looks like a "trapless system" with a water seal in the end to keep the steam from leaving the radiator and causing hammering in the returns.
Most of us here have a 0-3 psi gauge, reading in ounces of pressure to fine tune our vaporstats. Good luck.--NBC
@ March 3, 2014 10:01 AM in Banging in relation to PressureYou can do all your heating at well under a pound, even at 4 ounces.
There is probably a horizontal section supplying the radiator which is pitched backwards. Did you try raising up the radiator an inch or so? This will sometime correct a sagged horizontal which is halfway up the riser.
Don't rely on the settings of the pressuretrol without verifying the pressure with an accurate 0-3 psi gauge. When you adjust a pressuretrol down below its minimum, the linkage can disconnect, and allow the pressure to rise up too high. Those devices are works of the Devil! --NBC