EE-RM-TP-97-440 COMMENT 08CC

Oral Statement of 

Lou Sullivan 

Director, Split Systems 

Carrier Corporation 

Before the 

Office of Energy Efficiency and Renewable Energy 

U.S. Department of Energy 

on 

The Energy Conservation Program for Consumer Products: 

Test Procedures for Central Air Conditioners and Heat Pumps 

Docket No. EE-RM/TP-97-440 

As published in the January 22,2001 Federal Register 

March 29,2001 
EE-RM-TP-97-440 COMMENT 08CC

Test Procedures for Central Air Conditioners and Heat Pumps 

Comments of Carrier Corporation March 29, 2001 

Docket No. EE-RMlTP-97-440 

Good Morning. I am Lou Sullivan with Carrier Corporation, the world's largest 

manufacturer of air conditioning, heating and refrigeration equipment for commercial, 

residential and transportation applications. We employ over 14, 000 people in the US 

with 24 manufacturing plants in 17 states. I would like to thank the Department of Energy 

for the opportunity to address this workshop and present our views on the Test 

Procedures for Central Air Conditioners and Heat Pumps. 

Specifically, I would like to comment on three areas of the proposed rule: 

1) Defaults for the cooling and heating mode cyclic degradation coefficients (Cd's) 

2) The use of devices (e.g., thermostatic expansion valves) that help compensate for an 

incorrect refrigerant charging and insufficient indoor coil air volume rate problems in 

field installations 

3) Rating untested split-system combinations. 

1 )Efforts to seek new defaults for the cooling and heating mode cyclic degradation 

coefficients (Cd's) 

DOE should set new default Cd values for both cooling and heating. The industry has 

been aggressively working to improve the cyclic performance of this equipment for over 

two decades, since the inception of SEER. Many different methods to improve cyclic 

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EE-RM-TP-97-440 COMMENT 08CC

Test Procedures for Central Air Conditioners and Heat Pumps 

Comments of Carrier Corporation March 29, 2001 

Docket No. EE-RMlTP-97-440 

performance have been tried and several are being utilized in today's equipment. 

Improvements have been so significant that there is little opportunity for additional Cd 

improvement. 

The default value of 0.25 is significantly higher than the typical cooling Cd. The average 

Cd for fixed expansion device equipment is more like 0.10 for air conditioning units and 

0.15 for heat pumps. The most prevalent cyclic enhancement devices are indoor fan delay 

(TDR) and non-bleed TXV. Liquid line solenoids (LLS) and electronic expansion valves 

(EXV) are also utilized, but to a much lesser extent. Each of these enhancement devices, 

when applied separately reduces the Cd value by about 50%. If TDR is applied with 

TXV, LLS, or EXV, the Cd value is reduced another 50%. 

The industry members are spending a significant amount of test time and effort to 

determine the cyclic performance of systems. This testing serves only to document the 

system performance as required by law. Manufacturers can easily predict the Cd value for 

a given system, based upon the expansion and enhancement devices utilized. The testing 

simply confirms what is already known and wastes valuable time. Manufacturers could 

utilize this valuable test time to run additional steady state tests, such as ISO conditions or 

high ambient. The industry could also use the time to advance new HV AC technology 

and concepts, or resolve industry issues. 

The establishment of default Cd values will also serve to correct an inaccuracy in the 

NIST method for rating mixed systems. As written, this procedure gives a 5% credit for 

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EE-RM-TP-97-440 COMMENT 08CC

Test Procedures for Central Air Conditioners and Heat Pumps 

Comments of Carrier Corporation - March 29, 2001 

Docket No. EE-RMlTP-97-440 

non-bleed TXV usage stemming from improved cyclic performance. This credit does not 

account for the fact that the matched system may already have an improved cyclic 

performance through the usage of an indoor fan delay (TDR). While these two devices 

can be used together the improvement in the cyclic performance due to the TXV is 

nowhere near 5%. It is more like 1 to 2%. 

DOE should establish lower default Cd values and completely eliminate the cyclic testing 

option. Values for the fixed restrictor system, as well as the current enhancement devices 

(TDR, TXV, LLS, EXV) could be established immediately. This should be done in 

conjunction with the revised test procedures and not wait for the new minimum in 2006. 

If new enhancement devices are created, DOE should oversee a test program and assign 

the appropriate enhanced Cd level. 

2) Should changes be incorporated into the test procedure that encourage the use of 

devices (e.g., thermostatic expansion valves) that help compensate for incorrect refrigerant 

charging and insufficient indoor coil air volume rate problems in field installations? 

DOE should NOT consider changes to the test procedure that encourage the use of 

devices that help to compensate for improper charge or airflow. In order to consider such 

a change, DOE needs to fund independent research, which thoroughly examines multiple 

devices (not just TXV) and considers not only the benefits, but also the disadvantages. 

Carrier's written comments regarding the TXV question posed in the minimum efficiency 

NOPR were as follows: 

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EE-RM-TP-97-440 COMMENT 08CC

Test Procedures for Central Air Conditioners and Heat Pumps 

Comments of Carrier Corporation - March 29, 2001 

Docket No. EE-RM/TP-97-440 

Carrier agrees with the Department's assessment not to require TXV's on all equipment. 

In general, we do not believe the Department should be mandating a specific technology 

since this stifles creativity, innovation and competition. 

TXV's, when installed and sized properly, can slightly improve the performance of units 

installed with improper refrigerant charge or airflow. However, TXV's are not without 

problems. Since there are moving parts within these devices, they are potentially less 

reliable than a fixed expansion device which has no moving parts. Secondly, TXV bulb 

attachment and insulation of this bulb are critical to its operation. An improperly installed 

bulb can cause a TXV to "hunt" during startup and operation resulting in the HV AC unit 

never attaining its steady state performance. Lastly, a TXV, coupled with improper 

charge or indoor airflow, can create issues at the extreme ambient conditions. At low 

ambient conditions, indoor coil freeze-up is possible, and at high ambient conditions, 

compressor overheating and shutdown can occur. Until the Department thoroughly 

investigates TXV's and their alternatives, it should not require their usage. 

3) Should DOE pursue having one standard alternative method for rating untested 

split-system combinations? 

DOE should establish one standard method for rating untested combinations. Today there 

are inconsistent methods being used to rate mixed indoor coils. Evidence to support this 

are the many mixed ratings in the ARI directory which raise the efficiency of the outdoor 

equipment by 1 full SEER. Not so obvious are the mixed coils constructed with 

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EE-RM-TP-97-440 COMMENT 08CC

Test Procedures for Central Air Conditioners and Heat Pumps 

Comments of Carrier Corporation - March 29, 2001 

Docket No. EE-RMlTP-97-440 

considerably less material than the matched coils, but have the same ratings. 

The consumer is being misled to believe they are getting a more efficient system. Their 

installed system will use more power than the improperly rated system they purchased. 

Their electric bills will be higher as well. 

The utility companies and the country overall do not see the benefit of the power 

reduction from these improperly rated systems. Assuming these ratings are overstated by 

0.5 SEER and one quarter of the systems are sold this way, there are about 250,000,000 

more kilowatt-hours of power consumed in the country annually. 

The NIST Mixed Rating Method was never officially adopted by DOE. It is now out of 

date and did not account for indoor fan delay (TDR). 

The most significant shortfall is that the NIST procedure gives a 5% credit for a non-bleed 

TXV applied to a mixed system. The basis of this improvement is an improvement to the 

cyclic performance of the system (Cd). This credit does not account for the fact that the 

matched system may already have an improved cyclic performance through the usage of 

an indoor fan delay (TDR). While these two devices can be used together, the 

improvement in the cyclic performance due to the TXV is nowhere near 5%. It is more 

like 1 to 2%. 

The second potential shortfall of the current process is that each manufacturer may utilize 

their own simulation program after approval by DOE. As evidenced by the 1 full SEER 

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EE-RM-TP-97-440 COMMENT 08CC

Test Procedures for Central Air Conditioners and Heat Pumps 

Comments of Carrier Corporation - March 29, 2001 

Docket No. EE-RM/TP-97-440 

rating increases and the fact that the current TXV credit is 5%, another 5% increase must 

be coming from the simulation programs. This appears to be happening even when 

physical differences between matched and mixed coils are minimal. 

DOE needs to rectify this rating deficiency. This has been occurring for over a decade. 

DOE should develop new default Cd values and a select a single simulation program that 

should be used by the entire industry. DOE should complete this task in conjunction with 

the revised test procedures and not wait until the new minimum in 2006. 

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