heat pump thermostats

I bought a house with central air conditioning and propane heat. A couple of years later the propane furnace developed a crack so I replaced the fur nace with a high efficiency furnace. It and the air conditioning were put i n when the house was built 28 years ago. So when I found a outside unit h eat pump at the Habitat for Humanity store I bought it. And sure enough t he air conditioner stopped working well. So I enlisted the help from a sem i retired licensed air conditioning man and installed the heat pump and a n ew evaporator. Had to install a new evaporator because the heat pump uses R410a.

But the guy I hired has never installed a heat pump with a dual fuel system . So he is not much help with figuring out how to hook up the controls.

I want to use the heat pump when the outside temperature is warmer than abo ut 45 degrees and shift the propane furnace whon the temperature is colder. Sure I could save some by using the heat pump at lower outside temperatur es , but the underground storage tank agreement calls for using at least 25

0 gallons of propane per year. So why subject the heat pump to running at low outside temperatures.

So I am hoping to get some recommendations on thermostats and outside therm ostats. I do not want a system that connects to the internet. I do not ha ve a smart phone and do not know why I would want to control the house temp erature using a smart phone.

I probably left out some needed information. Oh yeah , I am an EE so you can rag me about that.

Dan

bout 45 degrees and shift the propane furnace whon the temperature is colde r. Sure I could save some by using the heat pump at lower outside temperat ures , but the underground storage tank agreement calls for using at least

250 gallons of propane per year. So why subject the heat pump to running a t low outside temperatures.

Well no help here, but with a bunch of head scratching and searching on the internet, I found what I needed to know. Also found a neat thermostat mad e in China. Search on WS1209 to find it. Only $1.29 and it just needs a l ittle help to work. It runs on 12 volts DC. So need to make a simple dc p ower supply that will use the 24 volts AC to power the unit. And need to s wap out the spst relay for a spdt relay. Then I can set it to route the he at signal to to heap pump when the outside temp is kind of warm and to the furnace when it is cold outide.

If anyone wants more info , just ask. Just be aware that I do not read thi s usegroup on a regular basis.

Dan