Geo Direct DX vs. Water-source: Capacity and Ratings
Brand / Model
Cooling Btuh
EER Rating
Heating Btuh
Cop Rating
 
 
 
 
 
Brand WF Envision ***
31,000
30
23,000
5
Brand WF Envision
40,200
20.1
26,300
4.2
Brand CM Tranquility 27 ***
28,900
27
22,100
4.5
Brand CMTranquility 27
38,200
18.2
29,000
4
Brand FHP Envirosaver
38,000
17.2
28,000
3.6
Earth Source Geo Direct DX
39,000
16.6
36,000
3.7
 
 
 
 
 
*** Low speed operation
 
 
 
 
 
 
 
 
 
Notes:
GPM
CFM
Drop off%
 
 
 
 
 
 
Brand WF [Low speed]
8
1000
Low speed
 
Brand WF [High speed]
9
1200
-27
 
Brand CM [Low speed]
8
1000
Low speed
 
Brand CM [High speed]
9
1250
-20
 
Brand FHP [single speed]
9
1200
-22
 
Earth Source Geo Direct DX
N/A
1200
0
 
** Drop off percentage is the value of heat energy not transferred during the heating cycle.  

Explanation

The chart above represents data available to the public from the American Refrigeration Institute [ARI] and the
manufacturers respective web sites. While to the untrained eye, the water-source numbers look impressive, however,
they are misleading. There are no accurate allowances for water pump operation. Field applications will vary greatly
from job to job. All systems mentioned are equipped with 3.0-ton capacity compressors.
Due to the poor performance
of the plastic ground loops, energy transfer losses through the water to refrigerant heat exchangers and waters
inability to carry heat energy, they do not produce heat capacities equivalent to their refrigerant capacities.
What
good are high efficiency numbers if the system has to be supplemented with another energy source that uses more
energy to meet the demand of the structure? The only other choice would be to increase the system size to
accommodate the additional load, which most likely will oversize the cooling system. In southern states where the
cooling season is dominant, this is not an issue. Where the heating season is dominant, it is a major issue.  

The Brand WF and Brand CM models have 2-speed compressors. The compressors drop to 67% capacity on low
speed [a 33% reduction]. Yet, the airflow values on both are only reduced approximately 17-20%. This allows for
higher energy ratings, but can cause comfort issues. In heating, less capacity and increased airflow reduces the
system discharge temperature. In cooling, less capacity and increased airflow reduces the latent capacity [humidity
removal] of the system.

The ESES Geo Direct DX system was ARI tested with a standard air handler [no Electronically Commutated Motor
{ECM} or other performance enhancing features. The Geo Direct DX system, when installed in conjunction with a
deluxe air handler, would produce efficiency ratings comparable to or higher than the water-source ratings.

Summary  

The ESES Geo Direct DX system, through its advanced design, is able to produce full heating and cooling capacities
throughout the operational range.
ARI Listed Capacity and Efficiency Ratings [3.0-Ton Ground Loop Heat Pump]