Problem

[Peter_1]

Tuesday, I visited a HP air/air monobloc.


Scroll Manuerop inside SZ090 on R407c, 3 phase.
Started up in heating mode: 3,3 bar LP (45 psi), 24.5 bar HP (355 psi)
Outside temperature 11.3°C (52°F)
Discharge temperature: 111°C, (232 °F) liquid 46.5 °C (116°F) suction right after the evaporator was 7°C (44.6°F)
Turbine Nicotra over the condensor 12/9.

Measured airvolume over condensor 2.400 m³/u (1413 cfm)

Opened valve till SH of +/- 7K
3.6 bar (52 psi) / 26.2 bar (380 psi) discharge 96 °C (205°F), liquid 53°C (128°F)

The unit works with a bad COP.

This machine is a replacement for a Carrier 50HS060

Inside is a liquid receiver without valves. I suppose both tubes are going to the bottom of the receiver. Otherise, I do'nt see how they circulate the liquid when reversing.

Complaints: client monitored power consumption since 1999 with the Carrier which was allways around 32000 kWh/year. Now this is increased to 43000 kWh/year.

When the units was just started, he had to reset the HP once a day, seems that this happened mostly after a defrost?
There's no suction accumulator.

Most important complaint is that during the coldest days, it took hours and hours to raise the temperature from 19°C to 20°C (66.2°F--> 68°F)
Reaching 22°C (71.6 °F) inside wasn't possibel when it was -3°C (26.6°F) outside.
The old Carrier HP could reach easily 25°C (77°F ) inside.

The old ductwork is still the same and in very good condition.
The ductwork is made of PU plates (alu foil inside) of 4 cm thick.

The suction on the condensor leaves the coil on the upper side of the coil. This seems strange for me...what about proper oil return?

Comments please .
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