Let me start out by saying that I know I'm probably not supposed to do this but I am on a fixed income. I do know enough about HVAC to be dangerous but am hoping to find a pro to start the new unit up after I install it.
I have an old 1997 3 ton coleman split system air conditioner and furnace. The furnace is an EB15 but almost all the condenser info is faded out. It looks like the unit charge (R-22) was 3.25 pounds. Since money is a concern, I want to replace the condenser with either a new straight A/c or even possibly install a heat pump to help out with the electric bills in the winter time. The thermostat in the mobile home is a 4 wire thermostat but it does have an 8 wire harness. The compressor has a 3/8 liquid line and a 3/4 suction line.
Questions I -
1) This 3 ton compressor has a 3/4 suction line and a pretty small charge. New 3 ton units all seem to have a 7/8 suction line and a much larger charge. Can I use the 3/4 line on a new unit in order to keep the original evaporator coil?
2) The new 2 1/2 ton units do have a 3/4 suction line and much larger charge and more than likely at least 3 seer rating higher. The mobile home is slightly less than 1000 sq. ft. Would a 2 1/2 ton unit possibly be big enough due to increased seer ratings or do other things have an effect?
3) I'm not real familiar with heat pump thermostats but basically does the orange (reversing valve) wire go directly to the heat pump or does it go to another connection in the heat exchanger? If it does, should there be any other problems with installing a heat pump instead of straight A/C?
4) My last option is to put in a R-410 A/C or heat pump. I realize that I will have to change the lineset and the evaporator coil so that is my last option. What I don't know is that if it work properly with an old heat exchanger.
Like I said before, I know everything should be matched up but I cannot afford to replace everything but would really appreciate any answers you may have to the above or any suggestions.
Thanks for your time and trouble.