Q &.A Heat pump
Many people are wondering about heat pumps. How does it work? What is the cost of a heat pump? How do I install a heat pump? In this article, we will attempt to answer the questions most frequently asked to us.
What is the price of a central heat pump?
The price of a heat pump depends on several factors. The main factors influencing the price of a heat pump are: tonnage, energy efficiency, technology, and the characteristics of the installation. For example, a central heat pump of 24 000 BTUs (2 tons) cost less than a 60,000 BTU's heat pump (5 tons). The same logic applies to the require level of energy efficiency of the unit. The price of a central heat pump will be higher for a device displaying a 20 SEER rating compared to a device displaying a 14 SEER rating. If the central heat pump uses an inverter type compressor (variable speed), the price will be higher than for the system operating with a standard compressor. The price of a central heat pump is normally in the range of $4000 to $7000 plus tax depending on the size and energy efficiency requirement. A home visit is required to estimate the proper size. This type of estimate is always free.
How do we install a central heat pump?
The installation of a central heat pump will take between 4 to 6 hours depending of the complexity of the installation and if it's a replacement or a new installation. The installation is performed by a team of two technicians. The installation of your central heat pump included the dismantling and disposal of your old heat pump (always included in the price) . The outdoor unit (condenser) will be placed on a wall mounted or floor rack. We will install a new set of refrigerant lines and a new evaporator (coil installed in the furnace). We take care of the electrical connection. The installation of your central heat pump will be fully functional on the same day.
How does a central heat pump work?
A central heat pump is a system that transfers heat from one space to another using a coolant. When refrigerant is evaporated (subject to a lower pressure), it absorbs ambient heat. When on the contrary it is condensed, it releases the heat it absorbed in. So during cooling, refrigerant is evaporated at low pressure in the indoor coil where it absorbs ambient heat and then be condensed at high pressure into the outdoor coil where it will release its heat. The central heat pump thus takes heat from the inside to remove him to the outside, in the air conditioning period. This is the same principle as a refrigerator. This heat transfer is made possible using the circulation of refrigerant between the two coils. During the heating season, the flow of refrigerant from the central heat pump will be reversed. The heat pump therefore take heat from the outside to evacuate inside. As unbelievable as it sounds, even when the air is cold, it contains energy.A heat pump always consists of an external condenser, an internal evaporator and copper lines connecting the condenser and the evaporator. The evaporator will be installed in a furnace (usually in the basement) or in a ventilator in the attic. To install a central heat pump, you must have ventilation ducts. The heat or cold produced by the heat pump will then be distributed in the house through the furnace fan and the ventilation ducts. The capacity of a heat pump is expressed in Btu and in tons. A Btu is the unit of measurement used to measure the heat output of a heating system. One tonne is 12,000 Btu
What is the energy efficiency of a heat pump?
The greatest benefit of using heat pumps is their energy efficiency. The energy efficiency of the heat pump is derived from its coefficient of performance (CP). At 10ºC, heat pumps, in general, have a CP of 3.3, which means concretely that for each kW / h of electricity they consume, they will produce 3.3 kW / H of heat. The heat pump produces more than what it consumes in electricity. This coefficient decreases as the temperature decreases as it is more difficult to recover the heat from the cold air. At -8.3ºC the CP is 2.3. When the equilibrium point is exceeded (point where another heating source is at the same cost as that of the heat pump), it becomes more economical to heat by means of the alternative heating source.
If you heat only electrically, your heat pump will reduce your heating bill by 30% to 50%. If you heat only with oil or natural gas, the heat pump will also save you 30% to 50% off your heating cost *. In addition, by being in dual energy (two sources of different heating, one with fossil energy), you will be entitled to Hydro-Québec's dual energy rate. In Montreal, the heating period lasts several months. Instead of your oil furnace working, it will be your heat pump that will run to around -12ºC. Then the furnace takes over. Calculate the number of days your furnace worked when the temperature is above -12ºC degrees celsius? Do you like to enrich the oil companies? In addition to saving $, you will reduce your ecological footprint and help reduce greenhouse gas emissions.
* The cost savings of heating depends on a number of factors such as: the HSPF rating of the heat pump, the prevailing climate conditions and the home specifications (insulation, heating preferences of the customer, etc).
Central or ductless?
We say that a heat pump is central when it is installed on a heating and cooling system distributing heat or air conditioning through ventilation ducts located in every room of the house. The system will be equipped with a forced air furnace (electric, oil or gas). A heat pump is considered ductless when the heat or cooling is distributed through a diffuser that is wall mounted. There is therefore absence of ventilation ducts. This type of installation is often used for condominiums or apartments. The ductless heat pump is very popular for single-family homes that lack ventilation ducts . The price of a ductless heat pump is generally lower than that of a central.
What is SEER and HSPF?
When we speak of energy efficiency for a central heat pump, you must linger in 2 key ratios: SEER and HSPF. The SEER rating stands for: Seasonal Energy Efficiency Ratio. This ratio assesses the energy efficiency of the central heat pump in air conditioning mode. The higher the rating, the greater the system is efficient and consumes little energy to produce air conditioning. The HSPF rating stands for: Heating Seasonal Performance Factor. This ratio assesses the energy efficiency of the unit in heating mode. The higher the rating, the higher the system is able to produce heating by using less energy. Obviously, energy efficiency has a price. The installation of a high efficiency central heat pump will cost more than a device with lower efficiency. However, with the steady increase in the cost of energy, it is more profitable to install a system with high energy efficiency.
1 stage, 2 stages or Inverter compressor?
How to differentiate them? The compressor is the heart of a central heat pump. Depending on the type of compressor installed, the heart will function differently. In the case of 1 stage compressor, when the heat pump is running, it runs at 100% capacity, consuming thereby maximum energy. The 2 stages compressor has the particularity of being able to operate at 2 levels of capacity: about 67% or 100% capacity. When operating at 67% capacity, the compressor uses less electricity. The heat pump is then in ''maintenance'' mode. It only maintain the required temperature while putting down regime. In the case of a Inverter compressor, it has the particularity to modulate its functioning as a variable light (dimmer). The operating range of an inverter compressor is from 30% to 100% of its capacity. The compressor modulate is operation according to demand. Power consumption is reduced at low speeds. Systems equipped with two stages or inverter compressor can be confusing for consumers who have been accustomed to the stop-start cycle of a conventional device. When the heat pump is in low speed, it works longer than a standard heat pump. Although it works longer, it is more energy efficient than a standard heat pump because the power consumption is at low regime instead of full capacity.
Explanation of a Inverter compressor: