Oversized unit

[alexdouglas1969]

Hi folks - I am coming to the end of my NVQ2 Refrigeration and have a long list of questions accross the board I still need help with. To kick off -

An oversized air conditioner e.g 14kw in a space with a 5 kw load will short cycle on temperature, right? But, will it freeze up? I can see no reason why, but someone at work told me that this would be the case? Also I am assuming the %SAT will increase...

Your thoughts ob what happens will be a big help!!

Lots more annoying questions still to come!!

Cheers!

[Gary]

Hi folks - I am coming to the end of my NVQ2 Refrigeration and have a long list of questions accross the board I still need help with. To kick off -

An oversized air conditioner e.g 14kw in a space with a 5 kw load will short cycle on temperature, right? But, will it freeze up? I can see no reason why, but someone at work told me that this would be the case? Also I am assuming the %SAT will increase...

Your thoughts ob what happens will be a big help!!

Lots more annoying questions still to come!!

Cheers!

If it is getting enough airflow through the evaporator coil for a 14kw system, then it shouldn't freeze up. If it is getting enough airflow for a 5kw system, it will freeze up in a hurry.

[Peter_1]

1. Most aircons evaporate above the freezing point of water, so the coil can't frost.
2. If it should evaporate lower then 0°C(32°F), then there's a small chance that the coil should frost very slightly while cooling.
But, most indoor fans of aircons runs continuously.
So it will reach very fast its room temperature (oversized and there will be not enough time to frost) but then the fans will continue to blow and the warmer room air will melt very fast the frost on the coils.

So, you are right.