1. NRL NRL - Welcome to the NRL Sales Training Program
The following presentation will provide information on Aermec’s new air to water heat pump

2. NRL Range Available Cooling only Heating and cooling mode Free cooling
High efficiency
EER 9.55 cooling only
COP up to 3.03 in W/W heating mode
Refrigerant: R410A
Heating Capacity: – BTU/h
Cooling Capacity: ton

3. NRL Range Working Limits: Heating / Cooling A5F/W104F - A32F/W131F
17 units with power supply 208/3/60
17 units with power supply 230/3/60
24 units with power supply 460/3/60
24 units with power supply 575/3/60
Standards comply with: ARI 550 UL ETL
Max water out 131˚F Heating
Min water out 21˚F Cooling

4. NRL Range NRL 280-1800 Cooling only
Cooling: 13.7T (48,2kW) to 130T (456kW) /3/60
NRL Heating and Cooling
Cooling: 13T to 130T /3/60
Heating: 13.8T to 135T /3/60
NRL Cooling only
Cooling: 145T to 261T 460/3/60; 575/3/60
NRL Heating and Cooling
Cooling: 140 T to 212T 460/3/60; 575/3/60
Heating: 145T to 225T 460/3/60; 575/3/60

5. NRL Chillers and Freecooling
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NRL Chillers and Freecooling
13 Through 260 Tons
Chiller or Heat Pump
Free Cooling Chiller
100 % Heat Recovery
40 % Heat Recovery
ETL certified
AHRI certified 5
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6. Hydronic Option Evaporator Air vent valve Water filter Flow switch
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Hydronic Option
Evaporator
Air vent valve
Water filter
Flow switch

7. The Aermec Advantage: Self contained units
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Advantages
The Aermec Advantage: Self contained units 4
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8. Hydraulic Options Hydronic KIT: 00 – Without
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Hydraulic Options
Hydronic KIT:
00 – Without
01 – Tank and low head pump
02 – Tanks and low head pump and standby pump
03 - Tank and high head pump
04 - Tanks and high head pump and standby pump
P1 – Pump low head
P2 – Low head pump and standby pump
P3 – Pump high head
P4 - Pump and high head pump and standby pump
NRL Multiscroll with R410A

9. NRL Multiscroll with R410A
Hydraulic Options
NRL Multiscroll with R410A

10. Capacity Control

11. Redundancy
NRL Multiscroll with R410A

12. NRL Multiscroll with R410A
Chiller
NRL Multiscroll with R410A

13. Desuperheater

14. Total Heat Recovery

15. Defrosting Heat Pumps
Aermec declares all defrost penalties in our certifications as it is a requirement in Europe. Competitors in North America do not as there the air to water heat pumps sold here are actually only certified as chillers
This chart shows the penalty that is paid between the temperatures of 31˚F 38˚F or the defrost zone. As you can see there would be a fair difference in efficiencies of units that do not declare defrost
NRL Defrost We must reach a low pressure minimum value to enter
into possible defrost mode. Only when the low pressure is below 61
PSI can we possibly go into defrost. If the pressure is above 61 PSI we
have no chance of needing defrost. Only after the pressure drops
below 61 PSI for more than 10 minutes will we enter on possible
defrost situation. If we reach these two conditions we can have a
defrost minimum every 30 minutes according to this parameter. The logic states that after 5 minutes of compressor operation we read
the low pressure and write it to memory inside the controller, this
becomes fixed value A. After that if the low pressure drops more
than 8.7 PSI below the fixed value A, we can have defrost. The
defrost is accomplished by reversing the cycle. The t t sbr parameter
is the delay time between two defrosts which is 1800 seconds.
So after the NRL has started and the compressor has run for 30
minutes, we read the low pressure and this is our value. When the
pressure drops down more than this differential, 8.7 PSI the defrost is
started as long as we have had a minimum of 30 minutes since the
last defrost. When the defrost is called for we stop the compressor
we reverse the four way valve and start the cooling mode while
stopping the fan. We stop the defrost by time or temperature, with
the minimum time being one and one half minutes and the
maximum time being 6 minutes. So we can stop the defrost by the
maximum time or when the liquid sensor on the liquid line before the
expansion valve reads 20 degrees C or 68 F.
When we have tandem or 3 compressors every time that one
compressor starts or stops we automatically recalculate the delta p.
There is a parameter inside the reading menu where you can see
the exact delta p. This allows you to see how many PSI of pressure
drop we have to wait to enable the defrost. If you go into the menu
through the display there is a parameter that is reading the
countdown of low pressure drops (it must be zero to authorize the
defrost).
We must also consider the unit has two circuits. The first circuit that
arrives at 8.7 PSI below the fixed value calls the defrost but we have
only one fan group so when the first circuit calls for defrost it automatically stops the second circuit. When we have two circuits
that are running and the first circuit or number one calls the defrost,
we stop the compressor on the second circuit. We perform the
defrost on the first circuit and then both circuits come back up in
heating mode. This is due to having only one fan group. When we
have two fan groups in the larger heat pumps they work
independently. A circuit is able to start and stop its own defrost. For
the smaller models where we have only one fan group it is necessary
to stop the second circuit to defrost one circuit. If you want to
accelerate the defrost you can adjust the parameter if you have a
unique installation, different working conditions, and area where the
humidity is very, very high and the temperature becomes very low to
have a fast defrost because otherwise if the low pressure never
drops down, it will never defrost, it cannot defrost. This is only through
reversing valve, no injection.
The defrost is also called if after 30 minutes of compressor run time
(times=0) but the delta low pressure is not reached and the LP is < 58
PSI (extreme working condition)
The 30 minutes are cumulative so if during the functioning
compressors are stopped we will consider the 30 min like real working
time. When compressor is stopped (it reached set point) at the next
start up it must operate a minimum 10 minutes before it is able to
enter defrost, of course if all conditions are satisfied.
The advantage of this system is that is auto adaptable at all working
conditions and defrost is called only when the heat pump is losing
significant performance.

16. How is Freecooling Made?

17. NRL Freecooling Air-to-water coil Ordinary chiller 3-way valve
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NRL Freecooling
Air-to-water coil
Ordinary chiller
3-way valve

18. NRL Free Cooling NRL Freecooling
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NRL Freecooling
Free Cooling Example: 45°F supply water with a ΔT of 10°F which
provides for a 55°F return water temperature. Chiller operates as a
standard chiller as long as the outdoor ambient air temperature is
52°F or above. When the outdoor ambient drops to 51°F or 4°F below
outdoor ambient the factory installed 3 way valve opens and directs
the water to the optional free cooling water coils.

19. NRL Free Cooling NRL Freecooling At the same time
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NRL Freecooling
At the same time
the fans go to high speed. The water gives up some of its heat
through these water coils and then goes through the refrigerant to
water heat exchanger where it is cooled to the desired temperature.
We have some free cooling along with mechanical cooling at this
point. As the outdoor ambient continues to drop we gain more free
cooling and use less mechanical cooling. The chiller will automatically start shutting off compressors as they the temperature
drops and they are not required. Eventually when the temperature
drops low enough the mechanical cooling is not needed at all and
we are using entirely free cooling.

20. NRL Freecooling The exact temperature that we
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NRL Freecooling
The exact temperature that we
reach 100% free cooling at depends on the return water
temperature but in this example we would each 100% free cooling
at approximately 29°F. The savings are tremendous and this unique
free cooling system is real advantage. The system is fully automated.
In applications where the chilled water temperature required is
higher e.g.: 55°F so the return water is 65°F free cooling would start at
61°F providing even greater savings.

21. Performance: E.E.R. Highlights
The graph shows what happens to the E.E.R. during one hypothetical year, assuming the water
temperature is constant at 44.5˚F, at different external air temperatures
You will notice the rapid increase of the E.E.R. when the compressors stop (i.e. 4 compressor refrigerant unit)

22. NRL Freecooling: Multichiller
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NRL Freecooling: Multichiller
Dualchiller:
Simplified control system to switch on and off, and command, two chillers (using Aermec GR3 command) in a single system, as if they area single units

23. NRL Freecooling: Multichiller
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NRL Freecooling: Multichiller
Multichiller:
Control system to switch the individual chillers on and off, and command them, in a system in which up to 9 units are installed in parallel, always ensuring a constant delivery to the evaporators

24. Thank You For Your Time
-You have successfully completed the IEC sales training program
-Thank you for your time