A Heat Pump is essentially the same as an air conditioner, but with one extra feature added. On cold days, a heat pump reverses its operations and heats the house instead of cooling it. What makes heat pumps stand out among other heaters is their heat gain. Today’s heat pumps at 0 Degrees Celsius outside return 3kw of heat for every 1 kw of electricity fed into them. It sounds too good to be true and immediately begs the question: Why don’t we use heat pumps in Toronto?
Low efficiency used to be the main reason. Up to 2006, most heat pumps were based on low-efficiency 10 SEER air conditioners, and they could not run at low outdoor temperature. In 2006 manufacturing of new units with less than 13 SEER efficiency was outlawed. Virtually overnight, new heat pumps’ efficiency increased by almost 30% and kept rising.
Heat Pump Pro’s
1. Heat pumps can be used in Toronto almost year-round. Air conditioners are only used for a few short weeks of summer.
2. The price difference between heat pumps and air conditioners is becoming smaller and smaller. Ductless units lead the way. Today ductless heat pumps cost only $200 more than their equivalent air conditioners. At this small premium, ductless heat pumps are already a no-brain winner against ductless air conditioners.
3. Central air heat pumps may still cost $1000 more that equivalent central air conditioner, but even at this premium a heat pump is an easy choice instead of an air conditioner if you use electricity, propane, or oil for heating.
4. “Smart” hydro meters are coming. Here in Toronto, electricity at night and on the weekends will cost only 3.2 c per kilowatt. At this price and at 300% efficiency, electricity is becoming the energy of choice for heating.
5. Heat pumps take advantage of global warming. As winters in Toronto are getting milder, heat pumps are becoming more profitable.
6. No reason to worry about carbon monoxide poisoning or fuel (gas, propane, oil) escape inside of the house.
Heat Pump Con’s
Heat pumps need supplemental heat. This can come from either a fuel-based furnace or an electric heater. There are two main reasons for this.
1. Because the same system is used for both heating and cooling, the heat pump is limited by the smaller of the two needs – the cooling one. On the coldest days of winter, the heating capacity of the heat pump may not be sufficient.
2. Cold outdoor temperature can also lower the heating capacity of the heat pump to the point where it has to be turned off and backup heat needs to be brought in.
Supplemental heat is not as a big a deal as it sounds. A couple of electric strips can be easily accommodated by the ductwork at a cost of a few hundred dollars. On the other hand, it may spare you buying a new furnace at $3,000.
And last, but not least – you can finally get rid of fuel heat inside of your house. People and fuels don’t really mix well in the same space.
By: Boris Sherman
So, your air conditioner has finally quit. A technician found that the condenser (aka outdoor unit), needs to be replaced. The other main part – the evaporator – is still OK, so you’re tempted to just replace the condenser. Don’t do it.
Let me explain. There are two main parts in an air conditioner, the evaporator and the condenser. You’ve never seen the evaporator. It quietly sits inside the ductwork and absorbs heat from inside air into the refrigerant. The condenser sits outside of the house and looks like it’s doing all the work. Actually, it’s only doing half the job. The condenser squeezes heat out of the refrigerant into the outside air.
Parts of existing central air systems aren’t good at all at adjusting to each other’s needs. If the evaporator absorbs too much heat from the house, the condenser will overheat. If the evaporator doesn’t absorb enough heat, it will freeze. The only way make sure an air conditioner will work properly is to match its two main components – the evaporator and the condenser.
It’s fairly easy to match components when you install a new air conditioner, as you can see in this article:
http://ezinearticles.com/?Buying-An-Air-Conditioner?-The-ARI-Reference-Number-Is-Your-Best-Friend&id=620937 However, it’s much more difficult to match the components of aging systems. Virtually all the systems that may require condenser replacement today were designed to work in 6, 8, or 10 SEER air conditioners. All the air conditioners on the market today are 13 SEER and up. Good luck matching 10 SEER (or even 8 or 6 SEER) evaporator with 13 SEER condenser.
This is why; if you have to replace your old air conditioner, replace everything.
By: Boris Sherman