Parking in the boiler room

Mike_Sheppard

How often do you get to park in the boiler room? This was a first for me!

hot_rod

probably nice and warm in there

JUGHNE

And not a cat litter box in sight!

VAsparky

Now that's impressive!

Solid_Fuel_Man

Nice Cleaver Brooks ya got there!

Mike_Sheppard

> @Solid_Fuel_Man said:
> Nice Cleaver Brooks ya got there!

They are pretty nice. We installed the Fireye Nexus controls on all six of them. Great control system. The three on the left are hot water boilers, the small one at the far end on the right is a hot water boiler, and the other two on the right are high pressure steam.

Solid_Fuel_Man

What kind of combustion numbers do you get out of those monsters?

Mike_Sheppard

Pretty standard numbers. 3-4% O2 in high, 4-5 at mid, and 6-7 at low. Those are standard 4:1 turndown CB numbers. A 10:1 turndown CB has to run leaner in low fire, 9.5-11% because there is much less air, therefore less turbulance and mixing. The real savings comes from the close control of the servo motors and O2 trim. There is an O2 sensor in the exhaust than monitors O2 and can make adjustments itself while running. That way you can bring the O2 down to 3% in high fire without risking it going too rich if the room conditions change.

A Limpsfield burner with Autoflame controls will run down to 2% O2 throughout the firing range.

Solid_Fuel_Man

The closed loop control with oxygen sensors is very cool. I'm glad boilers have finally caught up with cars 40 years ago.

When bosch invented the O2 sensor in 1976, auto-tuning fuel systems became reality.

I've played around with lambda (oxygen) sensors on gasification wood boilers for a few years now.

Mike_Sheppard

I think it’s a great feature. Some of the high efficiency condensing boilers in the commercial world are starting to come with O2 trim built in as well.

You still have to tune the boiler, but it allows the boiler to account for changing atmosphere conditions. It will shut the boiler down if the deviation gets too far from the O2 set point.

Jean-David Beyer

I park in my boiler room every night except once in a while in summer. Of course I have only one boiler with only 80,000 BTU/hour maximum input. And the boiler is actually in my attached garage.

It was about 15F warmer in my garage than outside. I would not think my boiler leaked so much heat into my garage. The only other sources of heat are the fairly long PVC exhaust pipe that goes across the ceiling of my garage (that never gets hot, though it sometimes gets comfortably warm), and the leakage through the wall into my house that has insulation in it. It is a mod-con and was supplying about 98F water to the slab at grade radiant heat.