Looking to power HVAC

[RCinFLA]

The RLA current rating is maximum load run current on compressor. Typically, should run about 60% of RLA spec number. Your compressor will not likely last long if running near RLA spec much of the time. At rated RLA current, the compressor head temperature gets quite hot approaching POE oil breakdown temperature.

As the outside temp gets hotter, the compressor head pressure rises, increasing compressor power requirement. Maybe at >120 degF outside air temp you will get close to RLA rating for run amperage. Overcharging of refrigerant charge also raises compressor run current. Another common issue is dirty condenser coil driving up compressor head pressure and current draw due to restriction of air flow over condenser.

Chart below is for my 4 ton Copeland scroll compressor unit versus condensing temp, which is in the middle of outside condenser, that is typically 10-20 degs F hotter than outside air temp entering condenser coil. The larger the condenser, the better the efficiency, the lower the high side pressure, and lower the compressor run current for given outside air temp.

My 240vac compressor spec'd RLA is 20.5A but it typically runs about 12 amps at 90 degs F outside air temp.

Typical low side evaporator temp (inside cooling coil) is 40-45 degs F for horizontal axis on chart. Inside air return temp going into evaporator coil is about 30-35 degsF above evaporator coil temp. Register outlet air temp is typically about 10-15 degsF above evaporator coil temp (50-55 degsF air temp at outlet registers) Dirty evaporator coil will restrict air flow over evaporator driving down evaporator coil temp, raising compressor compression ratio and raising compressor current. Once evaporator coil gets below about 30 degsF ice starts to form on evaporator further blocking air flow.

 

[Vigo]

the house has natural gas, but how to know if the heater is gas or electric ? the manual says it has both options

You might be better off starting your own thread.

As far as knowing if your heater is gas or electric, that should be pretty obvious visually once you go look at your inside air handler. Where is it in your house?

Also, keep in mind that a heat pump is anything that pumps heat from one location to another, and any air conditioner is a heat pump. But, we often colloquially use the term heat pump to describe a system that can reverse its refrigerant flow and pump heat from the outside IN instead of from the inside out. Just bringing this up to be aware that just because something says it's a heat pump doesn't necessarily mean it can reverse its refrigerant flow and do indoors heating with the compressor/refrigerant system.