Is this 1997 system still up to par?

04090

Its a 1997 Burnham V 907 boiler with a Beckett CF800 burner.



The boiler is rated for 534MBH and 1671 SF steam.  The burner has a 3.5 GPH nozzle summers and a 4.0 GPH winters.  There's a condensate tank, and it's worked pretty well over the years.  A 1970's Everhot tank hangs on the side.



Tried turning the pressuretrol down lower, but find it needs to be set to about 2.5 for the steam to reach the third floor. 



Is there anything we can do to minimize fuel use on this system?   It's using between 3500 and 4000 gallons annually.

BobC

Venting?

your 0-30PSI gauge is probably not very accurate at low readings, a lot of people add an auxilliary 0-3PSi gauge so they can see whats really going on at low pressure. If you have the old style pressuretrol there is a white knob inside and a screw adjusted scale on the face of the pressuretrol. What is that white dial set at and is the pressuretrol subtractive or additive (what model is it)?



My system runs just fine on 12 OZ and a lot keep theirs at 8 OZ maximum. Your system should run fine at 1.5PSI or less. For pressures less than 1.5PSI you have to replace the pressuretrol with a vaporstat. The usual cause of "needing" high pressure is inadequate venting. What kind of main vents does the system have? If this is single pipe steam what kind of radiator air vents do you have and are they all working. If it is a two pipe system are all the steam traps working?



Post some pictures of the boiler and the piping around it as well as pictures of both ends of a representative radiator (showing any valves or vents). That will letb us see what your dealing with.



Bob

nicholas bonham-carter

thirsty burnham

1997 was not so long ago, in boiler years unless maintenance was nonexistent, in which case 4 years might be the lifetime.

i wonder if the seasonal change of nozzles is necessary. has this boiler been maintained, particularly the burner?

as bob says, the pressure could be a lot lower with a vaporstat, verified with a gauge whose upper limit matches the setting on the vaporstat [my gauge is 0-15 ounces].

at these low economical pressures, the venting becomes critical. whether the system is 1-pipe or 2-pipe, the air must be allowed to escape easily, to allow the steam into the supplies and radiators. if 1-pipe, the main vents do all the work, and most likely the radiator vents will not need changing. a sign of bad main venting is often whistling/hissing vents at startup, and shutdown-how are yours?--nbc

04090

update

I have these pictures onhand and will update with more detailed



Would like to add a low pressure gauge to the right of the pressurertols - there's a plug there now.



There are two main vents by the boiler, one on each of two return lines.   I think they are Doles.  Sometimes the covers loosen from the base and they leak, but we just keep retightening them. 



Will be at the property again in a week.  Is there anything specific I should check on to post?

Gordo

I Would Check

At what level on the sight-glass the pump controller (the M&M 150) shuts off the boiler feeder pump.



If you install the M&M 150 according to B's published instructions, the water level is maintained at too high a level, IMHO.  It should be mid gage glass at most.



I've called B. about my concerns and was told that I was wrong in so many words by one of their engineers.  Who is right?  Your call.



Too high a water level causes lots of carry-over of water into the steam mains.  It's what I see in the field all the time with the V9s when controlled by M&M 150s installed "correctly". 

04090

On the level....

That's an interesting comment, and I wasn't aware of the ramifications.



An engineer once measured from the base of the boiler up and drew a pencil line where the water level should be.  It's midway on the sightglass.  The feeder maintains a water level very close to the top of the sightglass.  Some servicemen over the years have fliddled with the microswitches in the feeder, but it's remained at that level.



I've also attached a super magnet from a hard drive to the sightglass; it sticks to the metal protective metal rods and attracts the muck that's in the sightglass and keeps the water level within clear view.  It's worked well.

Gordo

If The M&M 150

on this boiler is maintaining the water level mid-gauge, that should be OK.



I'd also install a proper sight-glass blow-down valve on the gauge to check for excessive carry-over from the top of the gauge tapping while the boiler is steaming.

You open the gauge blow-down valve and allow the water to flow away for a bit, then shut the bottom gauge valve.  If  water starts flowing over the top gauge tapping down the sight-glass and out of the valve, you may have a surging/carry-over problem.



If it's not caused by the water level being too high, it may be dirty water.



I like your magnet idea to keep the gauge clean!  Very elegant.

04090

followup

The water level has been too high since day one, and some technicians have tried to lower it by fiddling with the microswitches in the feeder.  But that didn't lower the level any.  It's about 3/4 or sometimes slightly higher in the gauge.  Is that significant, and if so is there a workaround?





Was also contemplating a gas conversion to something like a Beckett CG10, which is the model listed in the manufacturer's literature.  Would that (1) work as well as oil has and (2) be something recommended we look into?   I have no idea what the cost benefits would be.



And yes, that magnet works well.  If I take it off, the crud floats around and it's kinda fun to swish it up and down the sight glass with the magnet.... the little kid in me will always be there.





Thanks for your help.

Gordo

The M&M 150 is set too high

I would have it removed and the 1" nipples changed to adjust the height so that the 150 maintains the water level at or just slightly above the middle of the sight glass. 



You don't want it too low, or you lose steaming capacity surface area and you may trip off the secondary low water cut-off.  Too high a water level, and you get wet steam (also not good).



Also,  I believe that when you touch the micro-switch adjustments, you break the lacquer seal on them and you bought 'em and all that goes with it.  I could be wrong about that, though.



Remember to put on a proper sight-glass blow-down (it usually code required anyway)

04090

Always one more thing....

The lacquer seals were, in fact, broken by an oil service company guy trying to lower the water some time ago.  Since then, the water level has not changed but the burner shuts off while the condensate pump is running, then when it shuts off the burner starts up again.  Would lowering the water level make a significant difference?



Thanks to scouring this site, I will be replacing a VentRite 77 return vent which steams throughout the heating cycle. There are actually two 77's installed, one on each of two return lines.  Should both be replaced at the same time, and should I use Gorton 1 or 2 for a 6000SF three story building?  Also, how low can a pressuretrol be set on a building that size?

Steamhead

Do these #77 vents

vent the steam mains thru those returns? If not, what does?



Measure the length and diameter of each steam main and tell us what vents it.  This will tell us what you need.

Gordo

#150 Adjestments

It sounds like the 150, in addition to being set too high, has had its switches maladjusted.



One of the switches should be set so that the pump comes on and feeds the boiler even as it fires.  The second switch, the one that shuts off the burner, should not need be activated unless the pump can't keep up with the water loss or the boiler feed tank has no water.



Lowering the 150 should reduce the rate at which the boiler is presumably geysering water up the pipes, thus allowing the pump to keep up. And thus allowing the burner to continue to run to the end of its cycle uninterrupted, thus going a long way to providing quiet, even, comfortable heat.



It also seems like you are going to need a lot of venting, then you'll be able to turn the pressure down. WAY down.



It is not the pressure that heats the building.  Pressure is only needed to get the air OUT.  Think in ounces per square inch.  If you need more than one psi, it is likely  your job isn't done.

Gordo

Master Trap

You also have what is called a "Master Trap" on the inlet of your boiler feed tank.



I am sorry to say, but that is an indication that something else is amiss in your system.



Master Traps are generally added by installers to cover-up a multitude of sins.



It is an all-to-common mistake.



Is this a one-pipe or two-pipe steam system?