Edvin
12-06-2011, 05:16 PM
Hi Guys,
Reading this forum, puting the theory together with my expierience I have some serious questions.
If it is a stationary unit(not transport), usualy the heat transfers and compressor rpm are constant.
As I have a lot of work with direct drive units I have question at what parameters should the TXV be regulated? (compressor rpm, condenser heat transfers) because as I noticed that the higher the compressor RMP are - the higher the superheat is, on the other hand when the car ir moving the with increases the subcooling so the superheat lowers.
And not always the more rpm the car has the faster it goes (this is not linear - nope You understand what I mean)
I think there are no problems with trailer units, because thay have constant engine speeds and almost constant heat transfer throu condensser.
Truck units have constant rpm, but the heat transfer changes
But in direct drive units all values change.
So the final question is at what rpm (idle or caompressor max capacityor middle) and subcooling value (theoreticaly) should the TXV be regulated.
Sorry for the novel, but I think this is very serious and everyone had broken compressors on direct drive units without any obvious resons.
Best regards, Edvin.
Reading this forum, puting the theory together with my expierience I have some serious questions.
If it is a stationary unit(not transport), usualy the heat transfers and compressor rpm are constant.
As I have a lot of work with direct drive units I have question at what parameters should the TXV be regulated? (compressor rpm, condenser heat transfers) because as I noticed that the higher the compressor RMP are - the higher the superheat is, on the other hand when the car ir moving the with increases the subcooling so the superheat lowers.
And not always the more rpm the car has the faster it goes (this is not linear - nope You understand what I mean)
I think there are no problems with trailer units, because thay have constant engine speeds and almost constant heat transfer throu condensser.
Truck units have constant rpm, but the heat transfer changes
But in direct drive units all values change.
So the final question is at what rpm (idle or caompressor max capacityor middle) and subcooling value (theoreticaly) should the TXV be regulated.
Sorry for the novel, but I think this is very serious and everyone had broken compressors on direct drive units without any obvious resons.
Best regards, Edvin.