evaluating school boilers: best replacement options
TRANSCRIPT
Integrated Design Solutions Architecture, Engineering, Interiors & Technology
EVALUATING SCHOOL BOILERS:
Bruce Snyder, CEM, LEED AP BD+C
October 8, 2013
BEST REPLACEMENT OPTIONS
Agenda
Background
Common Types of Boilers
Evaluating Existing Boilers
Boiler Efficiencies
To Condense or Not to Condense
Replacement Considerations/Options
Boiler Room Safety Features/Requirements
Utility Incentives
Q & A
Background
Current boiler designs go back well over 150 years.
Fire tube or “Scotch Marine” type boilers once powered
trains and ships.
Fire-tube boilers were one of the main engines behind
the industrial revolution, providing high pressure steam
to power factories.
Late 19th, early 20th century- 50,000 people per year
died from boiler and pressure vessel related accidents
in North America.
Background
ASME, ABMA, and NBBI helped develop codes and
standards to improve safety.
Once safety improved, boiler life, reliability and
efficiency became priorities.
Many different types of boilers began to be
developed.
Background
Cleaning the fire side
Cleaning the water side
Deteriorating refractory bricks
Addressing “thermal shock” or thermal stress cycling
Background
The advent of the flex tube boiler
Common Types of Boilers
Classic Fire Tube Boiler
Common Types of Boilers
Cast Iron/Cast Aluminum Boiler
Common Types of Boilers
Flex Tube Boiler
Common Types of Boilers
Horizontal Copper Finned Boiler
Common Types of Boilers
Condensing Boilers
Evaluating Existing Boilers
Type and manufacturer of the boiler
Number of boilers in the rotation
Maintenance history, water treatment
and air removal
Age of the boilers
Frequency of use/ Seasonal
Frequency of repair service
Video scope the interior
Evaluating Existing Boilers
Fire Tube = 40+ Yrs
Cast Iron = 35 Yrs
Flex Tube = 30 Yrs
Copper Fin =15 Yrs
Condensing, depends
on type and usage
Boiler Efficiency
Thermal Efficiency
Combustion Efficiency
AFUE (Annual Fuel Utilization Efficiency)
Boiler Efficiency
Boiler Efficiency
Determine your boiler
efficiency
Check boiler name plate
for input and output
i.e. INPUT: 5,000 MBH
OUTPUT: 4,000 MBH
equals 80% Thermal Eff.
Boiler Efficiency
How a condensing boiler works
Boiler Efficiency
Phase change captures a large amount of energy
Stack Economizer
Condensing HX
Boiler Efficiency
A stack economizer which preheats the boiler feed
water increases thermal efficiency by 1.5-2%
Boiler Efficiency
Visual depiction of the amount latent heat exhausted
and the damaging effects on metal.
Boiler Efficiency
Combustion efficiency
Boiler Efficiency
When fuel and oxygen in the air are in balance
the combustion is said to be Stoichiometric
Boiler Efficiency
Efficiency losses due to water side scale build up
To Condense or Not to Condense
New design
Off season requirements
Pool boilers
Year round operation
Does the amount of time the boiler “may” operate in the condensing mode save enough energy/money to justify the added cost of the boiler?
Run a computer model
Replacement Considerations/Options
Like and kind
Physical constraints
Thermal load verification
Degree of redundancy
Maintenance issues
Stack arrangement
Combustion air intake arrangement
Boiler Room Safety Requirements
Submit all plans to the State Bureau of Construction
Code for Plan Review
A multitude of safeties intrinsic to each boiler itself
Gas regulators- always vented to the outdoors
Temperature and pressure relief valves vented safely to
the floor
Boiler Room Safety Requirements
ASME code CSD-1 Rule 27 Annual Safety Testing
Do not use the results of the CSD-1 test as a
indication of the overall condition of your boiler
Boiler Room Safety Requirements
Boiler service clearances as
required by the boiler
manufacturer
Electrical clearances as
required by NEC and the
Michigan Electrical Code
Emergency off buttons for all
gas fired appliances
Boiler Room Safety Requirements
Meet combustion air requirements for all
appliances in the room
Create separation or add a refrigeration purge
system for a combined use space
Independently support boiler stacks, economizers,
combustion air intake ducts, inline pumps, etc.
Provide ample light not obscured by equipment
Eye wash or shower when chemicals are present
Utility Incentives
Utility Incentives
Consumers Energy
Gas Measure Incentive Changes The new incentives listed below are effective with all new applications submitted April 2, 2013 or later.
Contact Information:
Bruce Snyder
1441 W. Long Lake, Ste. 200
Troy, MI 48098
Phone: 248-823-2174
Email: [email protected]
Questions???
Integrated Design Solutions Architecture, Engineering, Interiors & Technology