Heat pump thoughts

Student 07 · 12-18-13, 10:48 AM

Hi Nonhog,
I can tell you about my experience with heat pumps in the NW. The Geothermal is great for the guys in the mid west and back east where the temperature is colder than their ground temperature for 6 months out of the year. Here in the NW with our moderate temps ( a week or two below 30* isn't cold) an Air Source Heat Pump is an economical and competitive alternative.
The new Heat pumps use R410a which is able to collect heat at very low temps (if I remember right less than 0*). Here on the west side of the Cascades there is usually only a couple weeks where we are below freezing. So, the rest of the time the HP is working very efficiently.
Heat pumps produce low heat, the old school heat pumps (air to air) used to blow "warm" air when compared to a NG furnace's hot air. People complained that Heat pumps didn't produce enough heat.
I was able to get around this "problem" in a couple ways. First I installed an air/ water HP (Daiken Altherma), water stores energy, so the low heat accumulates. Second, I only need low heat for the radiant floors. With HPs the less heat they have to produce, the more efficient they are.
I used to use Propane also, so I know what you're going through. Since their not regulated they can charge whatever they can get away with. My Heat pump is almost 500% efficient, it cut my energy costs to 1/3 of what it was with propane.
Most heat pumps use a 100% electrical "backup" in case it gets really cold. Straight electricity is still cheaper than most propane setups in our area ($0.11 kWh and $3+ gl propane). I would recommend you keep it simple and use the Heat pump alone, in our climate your "backup" heat source will never kick on anyway. Setting up the controls for a "Dual heat source" system can get involved and is a difficult DIY project.
I know you're not set up for hydronic heating. Your application sounds ideal for a couple mini splits, I am sure you will have no regrets. One thing I want to mention is that there is no silver bullet that works best for everybody everywhere, to be efficient you have to take advantage of what you have, whether it is solar energy or a mild climate. Good luck with your project, and let us know how it turned out.

12-18-13, 10:48 AM	#29
Student 07 Helper EcoRenovator Join Date: Dec 2011 Location: Gresham OR Posts: 35 Thanks: 0 Thanked 3 Times in 3 Posts	Northwest heat pumps Hi Nonhog, I can tell you about my experience with heat pumps in the NW. The Geothermal is great for the guys in the mid west and back east where the temperature is colder than their ground temperature for 6 months out of the year. Here in the NW with our moderate temps ( a week or two below 30* isn't cold) an Air Source Heat Pump is an economical and competitive alternative. The new Heat pumps use R410a which is able to collect heat at very low temps (if I remember right less than 0*). Here on the west side of the Cascades there is usually only a couple weeks where we are below freezing. So, the rest of the time the HP is working very efficiently. Heat pumps produce low heat, the old school heat pumps (air to air) used to blow "warm" air when compared to a NG furnace's hot air. People complained that Heat pumps didn't produce enough heat. I was able to get around this "problem" in a couple ways. First I installed an air/ water HP (Daiken Altherma), water stores energy, so the low heat accumulates. Second, I only need low heat for the radiant floors. With HPs the less heat they have to produce, the more efficient they are. I used to use Propane also, so I know what you're going through. Since their not regulated they can charge whatever they can get away with. My Heat pump is almost 500% efficient, it cut my energy costs to 1/3 of what it was with propane. Most heat pumps use a 100% electrical "backup" in case it gets really cold. Straight electricity is still cheaper than most propane setups in our area ($0.11 kWh and $3+ gl propane). I would recommend you keep it simple and use the Heat pump alone, in our climate your "backup" heat source will never kick on anyway. Setting up the controls for a "Dual heat source" system can get involved and is a difficult DIY project. I know you're not set up for hydronic heating. Your application sounds ideal for a couple mini splits, I am sure you will have no regrets. One thing I want to mention is that there is no silver bullet that works best for everybody everywhere, to be efficient you have to take advantage of what you have, whether it is solar energy or a mild climate. Good luck with your project, and let us know how it turned out.