Download - Refrigerant and Coil Coating Case Studies · Savings estimated using Trane Trace 700™ modeling software • One of the tested buildings was modeled and calibrated to utility bills

Rhode Island Convention Center • Providence, Rhode Island

Refrigerant Additive and Coil Coating Case Studies

Session: HVAC Technologies

Michael Bowers, PE, LEED Green AssociateAmec Foster Wheeler

August 10, 2016

Energy Exchange: Federal Sustainability for the Next Decade

Session Outline

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1. Identify Reasons for DX Efficiency Degradation2. Testing Methods3. HVAC Armor Test Results4. IceCOLD Test Results5. Combined Test Results6. Summary


Objective

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Direct‐expansion (DX) equipment begins to degrade shortly after installation. This study documents the efficiency gains of two

products that claim to increase the performance of DX equipment by tackling two major causes of degradation.

Condenser coil fin oxidation/degradation

Reduces oil fouling in refrigerant lines

Energy Exchange: Federal Sustainability for the Next Decade4

Efficiency of a System

EER, COP, EI, SEER, kW/ton…


Testing Methods


• Field Diagnostics’ HVAC Service Assistant– Instantaneous diagnostic equipment– Compares the pressures and temperatures of the refrigeration cycle against generic compressor data

– Calculates efficiency index (EI) EI =

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Testing Method – HVAC Service Assistant (EI)

Pros• Ease of use• Instantaneous calculations• Comprehensive data

analysis• EI is normalized for

ambient temperature

Cons• Single‐point data• Non‐industry standard

efficiency rating (EI)


• HVAC Armor testing method– Calculating change in enthalpy across the condenser– Data loggers obtain 20‐30 minutes of data

• Analyzed data is chosen based on finding a stable set of data in the temperature/pressure

– Data is corrected for ambient temperature

– COP =

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Testing Method – COP Data Logging

Pros• 20‐30 minutes of data

obtained• COP calculated before and

after implementation

Cons• Total system efficiency

based on assumptions of fully functioning system

• COP varies greatly during system operation


Testing Method – Compressor Amp Draw

Pros• Actual current draw• Full week of data to

analyze before and after implementation

Cons• Low sample size yields

unreliable data when corrected for ambient temperature

• Cannot account for changes in occupant behavior

• IceCOLD testing method– Amp‐draw was logged and analyzed– Data loggers obtained one week of data for baseline and one week of data for post‐implementation data

– Data is corrected for ambient temperature using cooling degree days (CDD)


• Total of 14 DX units were tested at various test sites in North Central Florida (12 units of valid data)

• Each individual circuit analyzed• Performance analyzed using three different methods

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Test Overview


Test Limitations

Imperfect equipment with imperfect data

Variables• Behavioral changes• Changes in thermostat setpoints• Voltage

Corrective Measures• Analyzed data with similar CDD• Eliminated data that were clear anomalies


What is HVAC Armor?

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• Inorganic coating for DX coil protection and rejuvenation

• Restores coil to original state• Prevents corrosion• ~1 mil coating allows for maximum heat

transfer and condenser coil airflow • Advertises 13% energy savings


Installation – HVAC Armor

Condenser coil is cleaned, combed, and coated with HVAC Armor


Testing Results – HVAC Armor

Percent Increase in EfficiencyTag Tons Pre‐EI

CU‐2 7.5 73CU‐5 15 111CU‐6 5 82CU‐7 10 78CU‐8 10 86RTU‐3 6 103RTU‐4 10 95RTU‐6 5 98

ton‐weighted average

Unit in worst condition yielded the highest efficiency gains

HVAC Armor % Increase

39%15.9%‐3.8%‐9.7%‐3.4%25%11%15.2%10.5%

EI% Increase

5%2%2%1%1%‐6%0%4%1.2%


Energy Savings – HVAC Armor

Savings estimated using Trane Trace 700™ modeling software

• One of the tested buildings was modeled and calibrated to utility bills

• Cost estimates provided by HVAC Armor• Electrical cost assumed to be $0.12/kWh

Payback varies for each unit, but can be maximized if unit is

properly screened for application

Tag Tons

CU‐2 7.5CU‐5 15CU‐6 5CU‐7 10CU‐8 10RTU‐3 6RTU‐4 10RTU‐6 5


*Paybacks must be analyzed against expected remaining life expectancy of the unit

HVAC Armor % Increase Payback

39% 0.74 15.9% 1.53‐3.8% ‐‐9.7% ‐‐3.4% ‐25% 1.0411% 2.1515.2% 1.5910.5% 2.50

EI% Increase Payback

5% 4.152% 13.372% 9.581% 19.871% 22.37‐6% ‐0% ‐4% 6.401.2% 23.56


What is IceCOLD?

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• Synthetic catalyst that reduces oil fouling in refrigerant lines

• Restores system to original capacity• Keeps system lubricated and prevents future

oil fouling• Advertises a 10% reduction in HVAC energy

consumption (average 15‐23%)


Installation ‐ IceCOLD

Refrigerant levels are measured* to calculate

correct amount of IceCOLD to add to system.

*Refrigerant levels were not modified as a part of this study


Testing Results – IceCOLD

Amp Draw (Amp‐hr/day/CDD)Analyzed by IceCOLD

Tag Tonnage Pre‐EI

RTU‐1 10 97RTU‐2 10 95RTU‐3 6 79RTU‐5 15 81CU‐2 7.5 74CU‐4 15 91CU‐5 15 113


IceCOLD % SavingsAmp‐hr/day/CDD

4.1%14.4%20.0%4.9%29.5%8.6%9.4%11.1%

EI% Increase

0%3%30%‐4%‐1%‐3%‐5%0.2%


Combined Effect


The combined system effect on the application of both products was analyzed for 28.5 tons of equipment.

Combined Effect

While efficiency gains can be realized by implementing both HVAC Armor and IceCOLD, the savings do not appear to compound on top of one another.

Majority of the energy savings will be realized after the first product implementation

74%

26%

Total Achieved Savings

First Product Second Product


What does all this mean?


Summary

• Increases efficiency of unit• Simple payback increases

substantially when you consider potential cost avoidance

• Energy savings confirmed for a small population of tested units

• Not cost‐effective to apply both products to a single unit• Screening of units is recommended prior to product

installation


Thank you for your time!

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Download - Refrigerant and Coil Coating Case Studies · Savings estimated using Trane Trace 700™ modeling software • One of the tested buildings was modeled and calibrated to utility bills

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