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1
PROJECT: IMPROVING AIR-CONDITIONING SERVICES IN OFFICES. OAS-07-002 (3W)
Champion: Chatiya Nantham (Head OAFA-FM)Team Leader: Juan Yu (OAFA-FM)Asst Team Leader: Alejandro Sta. Ana (OAFA-FM)
The Building Management System (BMS) is receiving an average of 133 complaints per month on air-conditioning services with 47 considered as “legitimate” complaints. Resolving these complaints systematically will assure the requestor that BMS is reliable and effective thus providing a well controlled room temperature that is comfortable and a healthy work place for the requestor.
CAV
Our AIM is to reduce the number of “legitimate” complaints from 47 to 6 complains per month.
3
C
CONTROL
August 2007
D DEFINE
May 2007
M
MEASURE
June 2007
A
ANALYZE
July 2007Week 1 & 2
I IMPROVE
July 2007Week 3 & 4
4
Problem Statement
There are on the average 133 complaints received monthly on air-conditioning services with 47 considered as “legitimate” complaints. Although many of these complaints are similar in nature, the problems are not systematically and timely resolved , in some cases resulting to recurring complaints. It is perceived to have negative impact on the customer satisfaction level.
Business Case Building Management System ( BMS ) is the front line to listen to complaints of staff particularly on the air con in their respective office. Resolving these complaints systematically reflects on the responsiveness of OAFA-FM and the service provider to assure the requestor that the BMS is reliable and effective. Consequently this action shall provide a well controlled room temperature that is comfortable and a healthy work place for the staff. The comfortable room temperature zone at ADB is set at 22.9 C – 24.9 C. Initially the project will be focused on the legitimate complaints of Hot room temperature (at above 24.9 C) and Cold room temperature (at below 22.9 C).
Goal Statement
Reduce the number of overall complaints by 30% from 1590 to 1113 annually thru the reduction of “legitimate” complaints to about 6 complaints per month from the present of 47.
5
C
TQ
Output
Output Characteristics
(big Y)
Project Y
(little y)
Measure
Specification Limits
Target
Defect
No. of Defect Opportunities per Unit
Comfortable Office Room Temperatures
Complaint –free air-conditioning services
Operations Definitions:
Monitoring and adjusting the temperature through BMS.
How process will be measured:
By complaints.
“6 legitimate complaints” or less per month
One opportunity per day.
Reduce overall complaints by 30% thru the reduction of legitimate complaints to 6 complains per month
Totalabove 24.9 degC below 22.9 degC within 22.9 to 24.9 degC
433 248 910
Sub-total
2 kinds of complaints: HOT and COLD room temperature. These complaints were group further into 3 categories: BELOW, WITHIN and ABOVE the comfortable temperature Zone.
LEGITIMATE COMPLAINTS : Hot complaints at room temperature above 24.9 C Cold complaints at room temperature below 22.9 C
COMFORT ZONE
7
Count
Perc
ent
AC complaint/category
Count25.1 16.1 10.0 5.6 2.1
Cum % 41.1 66.2 82.3 92.3
654
97.9 100.0
399 256 159 89 34Percent 41.1
Other
Hot (b
elow
22.
9 de
gC)
Cold (b
elow
22.
9 de
gC)
Cold
(with
in 2
2.9 to
24.9
degC
)
Hot (a
bove
24.
9 de
gC)
Hot (w
ithin 2
2.9
to 2
4.9
degC
)
1600
1400
1200
1000
800
600
400
200
0
100
80
60
40
20
0
Pareto Chart of AC complaint/ category
MEASUREMEASURE
This project will initially tackle the legitimate complaints: Hot-above 24.9C (25.1%) and Cold-below 22.9C (10%). These comprised 35.1% of the overall complaints.
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Summary of Legitimate Complaintsabove 24.9 degC below 22.9 deg C
2006 June '06 July '06 Aug. '06 Sept. '06 Oct. '06 Nov. '06 Dec. '06
Others (no action, start/stop aux. units)
0 2 2 0 20 0 0
2007 Jan. 07 Feb. '07 Mar. '07 Apr. '07 May ' 07
2
Others (no action, start/stop aux. units)
0 0 0 0
BREAKDOWN OF COMPLAINTS ACCORDING to CAUSE/CORECTIVE ACTION TAKEN
Complaints are further categorized according to causes/immediate corrective actions done on the complaints.
Analyze
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Count
Perc
ent
Problem Category_1
Count17.2 4.7 3.0
Cum % 37.6 75.1 92.3 97.0 100.0
210 209 96 26 17Percent 37.6 37.5
Other
Misc
Rese
t fan
pow
er or a
/c
Temp Se
tting
/Adj
Airfl
ow ad
j
600
500
400
300
200
100
0
100
80
60
40
20
0
Pareto Chart of Problem Category_1
Analyze
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Analyze
1. The complaints related to air flow adjustment and temperature setting adjustment accounts for 75.1% of the legitimate complaints broken down at 37.6% and 37.5% respectively.
2. The complaints which need fan power resetting due to malfunctioning of the unit and/or its ancillaries accounts for 17.2 % of the total complaints while 7.7% for the other causes.
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Legitimate Complaints (Outside Standard
Temp. Limits)
Room Occupant
Machine
Fishbone Analysis
Sensor location
Dress code
Geographical Origin
Temp. & air velocity Set point.
Defective field devices
Terminal Controller Malfunction
Room location
Heat load
Air flow req’t.
Health condition
NC
N
N
C
C
C
C
C
N
Room Thermostat
Pressure sensorDamper Actuator
FPU motor/blower assembly
C
Analyze
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Legitimate Complaints (Outside Standard
Temp. Limits)
Room
Machine
Fishbone Analysis
Sensor location
Temp. & air velocity Set point.
Defective field devices
Terminal Controller Malfunction
Room location
Heat load
Air flow requirement
C
C
C
C
C
C
N
Room Thermostat
Pressure sensorDamper Actuator
FPU motor/blower assembly
C
Analyze
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Verification
Complaint Temp. Date Location Problem Category BMS temp. readingActual temp. reading Error Problem
Cold 22 07/17/2007 RM5313Temperature Adjustment 23.5 23.3 -0.2 incorrect temp set point
Cold 22.19 07/19/2007 RM7716Temperature Adjustment 23.2 23 -0.2 incorrect temp set point
Hot 26.95 07/18/2007 RM4704Temperature Adjustment 23 24.1 1.1
sensor calibration & incor. set point
Hot 25.83 07/19/2007 RM2631Temperature Adjustment 23.5 24.3 0.8 sensor calibration
Hot 25.64 07/25/2007 RM3736Temperature Adjustment 23.4 23.9 0.5 incorrect temp set point
Hot 26.11 07/30/2007 RM3334Temperature Adjustment 23.5 24.1 0.6
sensor calibration & incor. set point
Hot 24.99 07/31/2007 RM5640Temperature Adjustment 23.5 24.2 0.7
sensor calibration & incor. set point
Verification of temperature adjustment related problem
Problems related to temperature adjustment are correlated to sensor calibration and incorrect temperature set point
Analyze
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Improve
Problems Causes Corrective Measures Action Plan Responsible
I. Air Flow Adjustment
Air Flow Requirement (inadequate or excessive)
clogged filter defective blower assembly stuck air damper/actuator unbalance air distribution improper setting of temperature
regular filter replacement periodic check up
conduct air balancing whenever there is a newly constructed offices
regular scanning of air flow setting at BMS
incorporated in the FPU PM program. (On-going)
air balancing coordinated with BCC to commence on October
BCC/ADB Engrs
II. Air Temperature Adjustment
Temperature Sensor
wrong location as a result of office alteration sensor inadvertently covered by furniture or some stuff inaccurate calibration of room temperature sensor dirty temperature sensor improper setting of airflow
standard positioning of thermostat to be included in AIG best practices
regular inspection of temperature sensors conduct regular scanning of temperature status at BMS
to be coordinated with ISO group. Document change to be completed on Sept. 30 2007. incorporated in the FPU PM program. (On-going)
BCC/ADB Engrs
PID/GSV
III. Resetting of Fan Power Unit
Building Automation System Network Communication
poor terminal controller response to the demand air flow and temperature. temperature controller does not response
Descriptive Statistics: Jun06-May07 stack TotalVariable Count Mean SE Mean TrMean StDev VarianceJun06-May07 stack 120 0.02025 0.00171 0.01824 0.01876 0.000352Variable Minimum Median Maximum RangeJun06-May07 stack 0.000000000 0.01583 0.11828 0.11828
June06- May07
Frequency
0.120.100.080.060.040.020.00-0.02
40
30
20
10
0
Mean 0.02025StDev 0.01876N 120
Histogram (with Normal Curve) of June06- May07
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Improve
Test and CI for One Proportion For July 2007 After implementing measures and control
Null Hypothesis : The recorded Proportion of Complaints from June-06 to May-07 against the total number of building occupants is equal to the July 2007 Proportion of Complaints.
Alternative Hypothesis : The July 2007 AC complaints proportion is less than the proportion of the complaints from June-06 to May-07
Minitab Results.Test of p = 0.02025 vs. p < 0.02025
95%
Sample X N Sample p Upper Bound Z-Value P-Value 1 29 2542 0.011408 0.014873 -3.16 0.001
Since the P-value is less than 0.05, reject the null hypothesis, and accept the alternative hypothesis.
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Improve
Minitab Results.Test of p = 0.02025 vs. p < 0.02025
95%
Sample X N Sample p Upper Bound Z-Value P-Value 1 30 2542 0.011802 0.015325 -3.02 0.001
Test and CI for One Proportion For August 2007 After implementing measures and control
Null Hypothesis : The recorded proportion of complaints from June-06 to May-07 against total number of building occupants is equal to the August 2007 Proportion of Complaints.
Alternative Hypothesis : The August 2007 AC complaints proportion is less than the proportion of complaints from June-06 to May-07
Since the P-value is less than 0.05, reject the null hypothesis, and accept the alternative hypothesis.
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CONCLUSION
The alternative hypothesis is accepted for our one-proportion test for both July and August 2007, we conclude that there is a significant reduction in air conditioning complaints after effecting the replacement of TEC and other air-conditioning control measures.
It is further expected that the number of complaints will further be reduced after we synchronize all measures that will lead to an effective result and meet our target.
Improve
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Control
Problems Causes Corrective Measures Action Plan Responsible
I. Air Flow Adjustment
Air Flow Requirement (inadequate or excessive)
clogged filter defective blower assembly stuck air damper/actuator unbalance air distribution improper setting of airflow
regular filter replacement periodic check up
conduct air balancing whenever there is a newly constructed offices
regular scanning of air flow setting at BMS
incorporated in the FPU PM program. (On-going)
air balancing coordinated with BCC to commence on October
BCC/ADB Engrs
II. Air Temperature Adjustment
Temperature Sensor
wrong location as a result of office alteration sensor inadvertently covered by furniture or some stuff inaccurate calibration of room temperature sensor dirty temperature sensor improper setting of temperature
standard positioning of thermostat to be included in AIG best practices
regular inspection of temperature sensors conduct regular scanning of temperature status at BMS
to be coordinated with ISO group. Document change to be completed on Oct.15 2007. incorporated in the FPU PM program. (On-going)
BCC/ADB Engrs
PID/GSV
III. Resetting of Fan Power Unit
Building Automation System Network Communication
poor terminal controller response to the demand air flow and temperature. temperature controller does not response
replace SMART controllers with TEC
On-going
PID/BCC/GSV
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OLD FPU CONTROLER MAINTENANCE CHECK FORM
Control
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IMPROVED FPU CONTROLLER FORM
Sensor to be check to include proper location or obstructions.
Velocity check to be implemented
Set point control to be evaluated
Control
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Control
FPU PREV. MAINTENANCE FORM
29
2007 Apr 16 – 27
Jun 25-Jul 8
Jul 23 - 26
Aug 6 - 17
Sep 3 – 15
Sep 24 – Oct 5
Oct 15 -26
Nov 5 - 16
LEVEL 2:
Level 2 zone 2/3 area
Level 2 zone 6/7 area
Level 2 zone 1/7 area
Level 2 zone 4/5 area
LEVEL 8:
Level 8 zone 6/7 area
Level 8 zone 4/5 area
Level 8 zone 4/3 area
Level 8 zone 1/2 area
TEC REPLACEMENT SCHEDULE 2007
Control
30
.
• Reduced complaints will free staff time to focus on proactive improvement
• Teamwork among service providers is critical
• Knowledge and understanding on operation of field devices is important to service providers
• Strict implementation of scheduled job plans
LESSONS LEARNED
31
PROJECT BENEFITS
• Efficient air conditioning services without increasing cost.
• Healthy and comfortable working environment
• Coordinated and streamlined preventive maintenance scheme