[barcooler]

If you put a new 13 seer fan coil in a system and keep the 10 seer condencer outside will this still balance out or will it cause execive compresser wear and cause a burn out?

[hvac1000]

You can do that but I recommend the use of an expansion valve with a hard start kit and a time delay os some sort on the low voltage signal source for the outside unit.

It is hard to get a good match with a piston with that combo so that is why I suggested expansion valve.

[barcooler]

The new coil has a txv and I quickly found a hard start was needed the unit ran for a few more days but jusy would not cool the space so they shut it down. When I checked the unit I had uwards of 35 degrees of superheat and no subcooling at all. I closed the liquid line valve to see how far down the compresser would pull, and found it would not break 0. I conclude the valves are not holding. I am still wondering if the mismatched seer ratings of the fan coil and the condencer had was the cause of this. Now there are other issues here I have not yet run a load calc on this room, it is a kitchen and I am not sure it was sized properly to begin with. I know the seer is a ratio of cooling over watts but do they not in part make these gains by altering coil sizes. There

[hvac1000]

the new coil has a txv and i quickly found a hard start was needed the unit ran for a few more days but jusy would not cool the space so they shut it down. when I checked the unit I had uwards of 35 degrees of superheat and no subcooling at all. I closed the liquid line valve to see how far down the compresser would pull, and found it would not break 0. I conclude the valves are not holding. I am still wondering if the mismatched seer ratings of the fan coil and the condencer had was the cause of this. Now there are other issues here I have not yet run a load calc on this room, it is a kitchen and I am not sure it was sized properly to begin with. I know the seer is a ratio of cooling over watts but do they not in part make these gains by altering coil sizes. there

If the coil came with a TXV was it for the correct refrigerant R-22 or R-410A?

If the unit was overcharged it is possible it will not be able to pump all the refrigerant down into the condenser.

If the unit was overcharged it is possible liquid flood back damaged the compressor valves.

If it is a commercial kitchen remember that air makeup might be needed to compensate for the range hood exhaust if so equipped and that will play a part in your calculations. Also remember to calculate the appliance heat gain and moisture discharge from the cooking.

A properly cooled kitchen will take a boat load of cooling BTU's and most companys usually do not really cool the kitchen but use the unit as a large dehumidifier since utility costs are so high.

Good luck.