Tests and performance tests on an air conditioning

Reversible Inverter heat pumps are "in fashion", many are installed either for air conditioning mode or for heating mode, or both.

What are the real performances of a 1st price heat pump (549 euros + connection kit)?

We tried to find out by estimating the instantaneous COP of an Airton Inverter model.

The external battery of this air conditioning is located in a greenhouse exposed full EST. Debate on the interest of placement of the outdoor unit of air conditioning in a greenhouse.

Mesures

Measurement conditions

Outdoor T ° (in the greenhouse): 36 ° C / 48% RH

° Indoor: 25.2 ° C

temperature set aircon: 32 ° C (max to avoid regulations)

blowing area of ​​the air conditioning: 0.0536 m²

Prince measures

Principle: the power of the air blown by the air conditioning is estimated by measuring flow rate and temperatures.

Measurements made using this anemometer which gives the instantaneous speed and T ° of the air flow.

Protocol: I 4 measurement points along the fan, as perpendicular as possible to the flow, I note and T ° km / h at each point.

The T ° must stabilize so I measure 1 minute after moving the anemometer.

We take the averages of these 4 points and we obtain a measurement of volume flow and “hot” T °.

I correct the volume flow with the density of the air (which varies greatly between 25 ° and 40 ° C) to obtain the mass flow of air.

With indoor T °, ​​it is a heat balance and we get the power restored heater.

I measure the electrical power consumed by a power meter on outlet

COP is obtained by dividing the 2!

Measurements (taken 10 minutes apart, starting at T = 10 min and in chronological order)

1 measure:

Pu = 1032W

T ° = inner 25.2 ° C
T ° = Hot 33.38 ° C
4.72 blower speed = m / s
Volume flow = 0.2527 m3 / s
Density at 32.5 1.155 ° C = kg / m3
(from http://fr.wikipedia.org/wiki/Masse_volumique_de_l%27air)
Mass flow = 0.2919 kg / s
Pc 1004 air = J / kg. ° C

Power output W = 2396

COP = 2.32

2 measure:

Pu = 950W

T ° = inner 25.2 ° C
T ° = Hot 36 ° C
4.35 blower speed = m / s
Volume flow = 0.2330 m3 / s
Density at 35 1.146 ° C = kg / m3

Mass flow = 0.2670 kg / s
Pc 1004 air = J / kg. ° C

Power output W = 2889

COP = 3.04

3 measure:

Pu = 650W

T ° = inner 25.2 ° C
T ° = Hot 39.4 ° C
4.19 blower speed = m / s
Volume flow = 0.2245 m3 / s
Density at 40 1.127 ° C = kg / m3
Mass flow = 0.2530 kg / s
Pc 1004 air = J / kg. ° C

Power output W = 3593

COP = 5.53

Conclusion

The last measured COP greatly exceeds the expected 4, the interest of placing the outdoor unit in a warm room is therefore confirmed. More analyzes in the link below.

More: debate on the real COP of an Airton air conditioning