EVALUATING SCHOOL BOILERS: BEST REPLACEMENT OPTIONS

Transcription

1 EVALUATING SCHOOL BOILERS: BEST REPLACEMENT OPTIONS Bruce Snyder, CEM, LEED AP BD+C October 8, 2013 Integrated Design Solutions Architecture, Engineering, Interiors & Technology

2 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

3 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.

4 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.

5 Background Cleaning the fire side Cleaning the water side Deteriorating refractory bricks Addressing thermal shock or thermal stress cycling

6 Background The advent of the flex tube boiler

7 Common Types of Boilers Classic Fire Tube Boiler

8 Common Types of Boilers Cast Iron/Cast Aluminum Boiler

9 Common Types of Boilers Flex Tube Boiler

10 Common Types of Boilers Horizontal Copper Finned Boiler

11 Common Types of Boilers Condensing Boilers

12 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

13 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

14 Boiler Efficiency Thermal Efficiency Combustion Efficiency AFUE (Annual Fuel Utilization Efficiency)

15 Boiler Efficiency

16 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.

17 Boiler Efficiency How a condensing boiler works

18 Boiler Efficiency Phase change captures a large amount of energy Stack Economizer Condensing HX

19 Boiler Efficiency A stack economizer which preheats the boiler feed water increases thermal efficiency by 1.5-2%

20 Boiler Efficiency Visual depiction of the amount latent heat exhausted and the damaging effects on metal.

21 Boiler Efficiency Combustion efficiency

22 Boiler Efficiency When fuel and oxygen in the air are in balance the combustion is said to be Stoichiometric

23 Boiler Efficiency Efficiency losses due to water side scale build up

24 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

25 Replacement Considerations/Options Like and kind Physical constraints Thermal load verification Degree of redundancy Maintenance issues Stack arrangement Combustion air intake arrangement

26 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

27 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

28 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

29 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

30 Utility Incentives

31 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.

32 Questions??? Contact Information: Bruce Snyder 1441 W. Long Lake, Ste. 200 Troy, MI Phone: Integrated Design Solutions Architecture, Engineering, Interiors & Technology