Help theary

[hvacrmedic]

OK. I still dont understand. Maube I did not explained well the problem. We have compressor, evaporator, TEV and condesator. Condensation pressure is kept constant. Machine works in design mode. Now, load is decreased, so superheat is decreased and TEV closes, that results SST to decrese. If load continues to decrease, SST will drop more and this will cause head pressure to drop. When head pressure drop, condensator fan will decrease speed, so more flash will be in evaporator, and this will increase superheat and this will result in TEV opening, that will result in SST increase. So now one fan work with decreased speed, matching the load. Where is the limit of this way of capacity reduction? And how it is posible to subcool the water when machine can match reduced load?

During pull-down the machine capacity will always be greater than the load. If a balance point is reached where capacity is equal to the load, then a steady state condition will occur where the temperature will not drop any further. The fan cycling isn't for "matching the load" it's to maintain head pressure during low ambient conditions, to allow proper feed to the TEV.

[Lambo]

During pull-down the machine capacity will always be greater than the load. If a balance point is reached where capacity is equal to the load, then a steady state condition will occur where the temperature will not drop any further. The fan cycling isn't for "matching the load" it's to maintain head pressure during low ambient conditions, to allow proper feed to the TEV.

OK. I think I understand now. Thanks for effort.