- It covers the entire house for both A/c and Heat..including the cellar. There is at least one register in every room of the house except the upstairs bathroom(not needed if the door is open) and my network room(do not want heat going in there). A/C is handled by a different system if required.
- This is a “dual-fuel” hybrid system. It has the usual a/c capabilities but it also has a heat pump as the outdoor unit as the primary heat source. Once the temperature gets below 35 degrees it switches to an oil furnace that is built into the indoor air handler unit.*
- This system now covers the entire house from the upstairs(including the hallway) to the cellar(a smaller amount is diverted there simply to prevent freezing in the winter and to aid in humidity control in the summer).
- The new system is rated at 105,000 BTU/hr instead of 85,000 BTU/Hr.
- The new system keeps the house at a programmed 64 degrees during the day vs 60 degrees for the old system.
So far this new system is saving me money all year round. My electricity bill went up from @105/month in the summer to about @140/month. However the entire house is at the same temperature instead of just a couple of rooms. That rise in costs also includes the increase in power draw from the infrastructure upgrades(a constant 300Watts) i did around that same time to improve my business back-end infrastructure.
Now that wintertime has sunk its teeth into this area I am able to evaluate the heating costs. During November more than half of the month was spent on the heat pump. The electricity bill went up about $10/month so far due to the increased use of the hvac system in heat pump mode. Now that i have been on a steady diet of oil for the past month I can also evaluate the oil usage. With the old system we would go from a full tank to less than half a tank in a month. In really frigid times that old system could not stop the house from developing a chill that would make it uncomfortably cold in the house requiring a bump to about 62. The old system would be struggling to keep up 60 degrees much less 62. With this new system, the burn rate is actually less. We are at, as i write this, just above 1/2 tank…but the system is at 64 degrees and there is not a chill in the house. The system is also not having to run very much to maintain that temperature. So an uprated system covering a larger area, while maintaining a higher internal temperature with higher efficiency = less cost to heat the house in the same conditions as the last system. I will probably spent less than 1k on heating oil this year.
Now it helps that I did a ton of research on various systems while also taking into account our climate in the past here and a close eye on fuel consumption, the pros and cons of various heating technologies, and the costs involved. Luckily oil prices have been stable the past couple of years so a direct comparisons was easy to do. Having a dual fuel system is highly advantageous in this area.
* This is one reason when I installed my new HVAC system i went with a heat pump/oil furnace hybrid. When it is above 35 degrees heat pumps work well…below that and they just run themselves to death. Below 35 degrees my system switches to the oil furnace. heat pumps cannot operate with any real efficiency below freezing…so you wind up on the electric heat coil system(which is nothing more than a huge set of electric baseboard heaters). This spikes the crap out of your electric bill. When you are in “emergency” heat mode your efficiency is 1 to 1. You get one dollar of heat for every dollar of electricity. With oil it’s much higher. A properly maintained, high-efficient oil furnace has approximately 139000 BTU’s of energy per gallon. right now oil prices are hovering at @2.95/gallon. Sure oil heat gets expensive because you see the bill immediately with each fill up. Over time though it is cheaper than electric heat. Heat pumps work according to their SEER rating. IN a highly simplified nutshell the minimum temperature for most heat pumps is 32 degrees…below that and their efficiency quickly approaches that of baseboard heat. Get them into real cold(like below 20 degrees) and they actually burn more money in power usage than heat they produce. If your heat pump is more than 10 years old I would highly advise you look into replacing your heat pump with a newer, higher seer heat pump and back it up with an oil furnace. There are some heat pumps rated for teens and below…but their efficiency at that point is barely above electric baseboard heat. I know of a local business facing this. Their location has the split ductless systems that promise to be able to heat at temperatures as low as zero degrees. Last night, with the thermostats set at 50 degrees the heat pumps could not keep up with the temperatures here in Brunswick. Despite the fact it got to “only” 10 degrees the building was 45 degrees. The heat pumps(which is what split ductless heaters are) ran continuously from midnight onwards. Their building right now(as of 10am) is hovering around 55 degrees and slowly rising. The temperature outside my house in 16 degrees. The client called me asking if her networking equipment is ok..to which i replied, “yes your equipment and servers are loving this”. There is monitoring software running on their servers that e-mail me every half an hour..which is how i know at least what temperatures the servers are seeing…