Post your electric rate in cents per kw-hr, and your gas rate in either $ per ccf or $ per therm. The heat output of a gas furnace is very similar to electric resistance strips if enough kw are used. Utility costs decide which is cheaper. 5 kw electric strips put out air temps about 15F greater than room temperature. So a typical 10kw strip heat puts out 100 degree air if the room temp is 70F (70 + 30 = 100). This# is based on 1200 cfm air flow from the indoor fan. 15kw = 115F which is more in the range of gas furnace temps. The air handler must be sized to handle this heating load. These temps are for the strip heat only and do not include any btu's from the heat pump. The heat pump itself puts out air temps from about 90F to 100F based on outdoor air temps. The 90F supply temp air from the heat pump combined with 20 kw aux electric strips provides minimum 120F output air when needed. Heat pumps provide enough heat up until the balance point, which is around 32F or so based on home construction/insulation (mine is 25F). At temps lower than the balance point, aux heat is needed - either furnace or strips. The good thing with the strips is they can run along with the heat pump. The furnace cannot run when the heat pump is in heating mode; its one or the other. When the heat pump goes into defrost mode, the air output is in the low 50's. 10 kw provides 30F to temper the air into the low 80's so it doesn't feel too cold while the heat pump is defrosting. The furnace will provide 120F air during a defrost cycle. The heat pump is typically 300% efficient down to 35F ambient. Heat pumps make cheap heat. One comment about the XP-19. It's "up to 19 SEER". Not all combinations get 19 SEER. Model numbers can be used to determine actual SEER. Also, dual-compressor systems like the XP-19 are more for hot and humid summers than for heating. In the cooling mode, running on 1st stage saves $$ and reduces humidity. Once on 2nd stage, it loses its operating $$ benefits. A 14/15 SEER usually provides the best combination of purchase price and operating cost. If you can afford a "19 SEER" system, go for it. Whichever SEER you get, you want as close to 12 EER and 9 HSPF as you can get for low operating costs in cooling and heating respectively. Good luck.

I am in agreement with everyone, the unit is old but as stated, was purchased by TRANE. However, the relays and other supporting parts are readily available. If I'm correct, I think Tigerdunes was pointing in the right direction. If you are not familiar with heating with heat pumps, then the air coming from the vents while in the heat pump mode alone, would feel cool to you. One thing you mentioned was that while it was in the heat pump mode, you did not measure voltage to the element. That would be normal. When the unit calls for AUX or Emerg. heat, then you would get a voltage to the heaters. Here's what I think is happening....the reversing valve is stuck...it was common on the older units. The unit stays in the cooling mode and when the first bank of heaters comes on, the cool air overcomes the full effect of the heater. Check the air coming from the outside unit. If it is warm and that will confirm the possibility of a stuck reversing valve. As mentioned also by Tigerdunes, replacing a reversing valve is expensive and given the age of your unit, whole replacement of the unit would be a better choice. Now a professional should be called however, I'll give you one thing you can try, if indeed it is still in the A/C mode. You can force the valve to slide into the heat mode by doing this.....disconnect the blower at the condenser. Turn the unit on in the heat pump mode and let it run....Given your temperatures, the condenser will slowly build pressure on one side of the valve as the pressure drops on the other side. You'll know you are getting close when you hear the compressor staring to load up. You'll suddenly hear a whoosh and the reversing valve has now reversed. Let it run for about a minute to make sure it has fully reversed. Shut the unit downand hook the fan back up. When the unit goes into the defrost mode, the valve may work and the unit defrosts but may not switch back to heat mode (sometimes they do, sometimes they don't.) If that's the case, you have to do it all over. This suggestion is just to get you some heat until you get someone out.

Absolutely disagree with above post. Bryant is sister company to Carrier and model to model is same except for cabinetry. The idea that Bryant is cheap Carrier is simply not true. now to your post. What size is existing heat strip? I don't like the Bryant configuration. An Evolution condenser with a Preferred series VS air handler. I would suggest dropping down to the Preferred HP Mdl 226a which should save you some bux. Add Bryant Edge Thermidistat. Any heat strip sized above 10 KW should be staged. Still prefer HPs with demand defrost which neither Bryant nor Goodman offer. I would not have a Goodman. Still prefer HP systems that have demand defrost like Trane/AmStandard.. 6937312 Active Systems BRYANT HEATING AND COOLING SYSTEMS PREFERRED SERIES PURON HP BRYANT HEATING AND COOLING SYSTEMS 226ANA036****B FV4CN(B,F)005L 1050 840 36400 13.00 16.50 35400 9.00 22600 1 HRCU-A-CB 267 754 Yes IMO

Is this a single story home? Are there multiple rooms to be cooled? Mini splits work for open spaces. Houses built in the 70s typically were built with multiple walls. You would need multiple mini split heads which makes it expensive. You already have a nice heating system. The air handler and duct work in the attic would be a good cooling solution. Keep looking for more HVAC contractors. The first two have proposed expensive solutions which are not the appropriate in my opinion.