Help with a new Duel Fuel Conversion - Noisy burner always running on high

josepha

Recently upgraded a building I manage in NYC to duel fuel from oil #2. Realizing some savings through this first season, though suspect there is good deal off opportunity to save/adjust, along with some noise issues that was hoping someone can help with

Setup
- 23-units, 4 floors, (6 per floor w/ exception of first floor)
- BOILER: BEST- SCOTCH MARINE 5A - 40
- BURNER: CARLIN Duel Fuel Burner 702 G/O
- CONTROLS: Older HEAT-TIMER MPC (Fairfield gold series edition-see attached) with external sensor and return line sensor.
- OIL TANK: 2,000 gal #2

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1

There have been complaints of the burner being too noisy for the units directly above. What they are hearing is the burner. I believe the burner is always running on high and never lowering throughout the heating cycle. Have had somebody to adjust it, but does not appear to be helping.

2

The apartments are being overheated and not sure best way to adjust the existing controls or if controls should be replaced with something newer (if that will have a sizable effect).

3

Not sure if this is even related to the boiler operation in this first heating season after the conversion, but the water usage for the building has skyrocketed since mid Nov. Possible that the boiler could be using that much more water?

4

Can anyone suggest some opportunity for better efficiency and smoother operation? Afraid I am a bit green, but have heard that venting the main lines can help remove air and even steam distribution and reduce the need to overheat to a higher psi?


Thanks!

JStar

We're familiar with that 702 burner. Is it set up with a separate pressure control to trigger low fire?

nicholas bonham-carter

Examine that water use situation closely, by valving off the auto fill to the boiler, and checking the level on the sight glass frequently. Clothes pins are good markers for the level. See how long it takes to get to the LWCO cutoff.
On a cold day, If you have access to the roof, see if your chimney is showing more white steam vapor than the neighboring buildings, (although they could be leaking as well!) Maybe we should devise some sort of test for determining the presence of steam in the flue down by the boiler. If you have any suspicions, then the overfill test will show up any boiler leaks, but that will put the boiler off line for a few hours. It is most important to correct any leaks, before the situation becomes terminal. Since you have a fire tube type boiler, tube replacements can always be made, up to a point. If the boiler has to be replaced, then you could consider installing several smaller boilers, whose total EDR square foot ratings equal the total of the building radiation. These could be fired in stages on pressure, for great economy, but of course smaller burners Are not available in dual fuel configuration.--NBC

josepha

@JStar‌
Going to take a closer look at the setup to look for a separate pressure control to trigger low fire (and snap some pictures)

@nicholas bonham-carter‌
I will try to cutoff water and monitor closely for when it gets to LWCO. Should I be troubled if it gets there in a short period or at all?

I'll check the chimney as well.

Forgive my ignorance, but what is the overfill test? Note: this is a one pipe system.


Thanks!

JStar

@‌josepha

If you need any field service or a general assessment, I'd be happy to help. I service NYC.