Dear Refrigeration Engineers,

Below we would like to ask for your help.
We are to replace the controller and display of an Aermec heat pump with the following data:

Controller data:
CAREL
Product code: PC02000AL0
Serial number: 0144673 Rev. 1.716
Date: February 6, 2006

Data of the regulated heat pump:
AERMEC WSA1251H
Serial number: 0802006135540003
produced: 2008.

Display data:
CAREL
Code: PC01000CBB
Serial number: 0281524 Rev.2. 110
Date: January 18, 2008

Aermec's Hungarian representative informed us that the new PCO2 controller is no longer available and instead offered a compatible PCO5 controller programmed according to the parameters.

New contoller (PCO5) data:
CAREL
PCO5+HS
Serial: A00522593
date: 2023.11.21
SW: RVNW542_PCOS+_HS

We ordered 2 of them with the corresponding display.
Unfortunately, during installation we discovered that the new controller is not compatible with the device, it gives false errors that do not exist: low and high pressure errors at the same time (AL011 and AL009).
The Hungarian delegation inspected the equipment on site but was unable to provide any significant assistance. He suggested that we contact a brand service in Hungary. That's what happened, they also examined the devices on site, but can't suggest a sensible solution either.

They promised to send the problem to the Italian manufacturer and request assistance for a solution.

To date, we received no proposals that have led to results.
What do you recommend, what can we do to ensure that the ordered parts can become a properly functioning, compatible part of the Aermec heat pump?

Looking forward to your suggestions and help,

M S AIR – Hungary