Compressor Overload Error

[R0berts]

Hi,

We are facing a strange issue at site. (Basically its a Hotel). I will narrate the whole scenario;

We have Acson ACC25C (Ceiling Concealed) units installed. The Hotel Management uses Key Cards to energize lights, appliances and air-conditioners. When a guest arrives he uses the Key card to energize the whole system, the air-conditioner works absolutely fine without any problems. Once the guest leaves, he simply removes the Key Card and the whole system is d-energized. The Hotel staff comes back in to check the room before they officially sign off the guest slots in the key card, remains there sometimes for more than 3 minutes and sometimes less than 3 minutes and leaves. Then he comes back does his cleaning etc and leaves. Now say if a new guest comes in after a day or so or the hotel staff visits the room prior to the arrival of the new guest he slots in the key card, at that very instant the SLM 3 controller of the air conditioner displays E4 error - Compressor Overload Detection Error. Now this is very strange as the unit was not in use it was completely Idle prior to this then why do we get the Compressor Overload Error.

The manual states that the Compressor overload error is either due
1. Indoor/Outdoor coil sensors being short or
2. The high pressure switch (normally close) which is in series with the power supply to the controller.

However point number one is not the root cause as the unit is not operational and when it is operational the error never comes up. The error only shows when the unit is turned on after couple of days rest.

The manual states that during the first cycle of thermostat on since power on reset counter is increased by 1 and timer starts to run. Now if timer exceeds 3 minutes or the unit is turned off the counter is reset to zero. And if the counter is greater than 5 the unit will display Compressor Overload Error. Some of my colleagues are saying that as the unit is not properly switched off through the SLM 3 controller the controller retains the counter value of 1 in its non-volatile memory, now another person comes in slots in the key card leaves without properly switching it off via the controller, however the counter has stored 2 in its memory and so on till it reaches 5 and on 6th attempt it displays the error.

Me and a couple of my other colleagues think otherwise. How can we tell the Hotel Management or the Guests to switch off the Air-conditioner through the controller and not just by plugging out the key card. There has to be another way. Or may be there is a design related fault.

I know its lot of literature. But I would appreciate if I can get some help and expert views on this. If you need any other information or if u cant understand something due to my English then please feel free to ask. (English is not my first language)

Regards,

[install monkey]

take the air con off the card reader- just have it so it works via the remote control- housekeeping can turn it off when they clean the room