Heat Pump Balance Point Calculator: Optimize Efficiency and Comfort
As an HVAC professional with more than a decade of experience, I have assisted hundreds of homeowners in getting the best possible performance from their heat pumps, particularly in extreme cold. One very important term that is often missed is the balance point.
In this post, we will discuss:
- What a heat pump balance point is (and why it matters)?
- How to calculate yours accurately?
- Tried and true ways to improve efficiencies; and When to call an expert.
In addition, I will feature my favourite heat pump balance point calculators, so you can make the best data-based decisions for your home.
Heat Pump Balance Point Calculator
The blog will include the following discussions:
The definition of the balance point heat pump concept.
- How heat capacity is related to outdoor temperature according to a balance point graph.
- Using a heat pump balance point calculator to find that temperature.
What is Heat Pump Balance Point?
Heat Pump Balance Point is the outdoor temperature at which heat delivered by the heat pump alone can meet the need for heating of the building-or rather heat pump stage-off to any kind of backup heating.
The balance point lies between 30 and 45, depending on:
- The heat pump's efficiency and capacity.
- The insulation and heat loss characteristics of the building.
- Indoor temperature settings.
In temperatures lower than the balance point, the heat pump cannot provide sufficient heat to sustain indoor warmth, and auxiliary heat will be required to cover the shortage.
How Does Heat Capacity Relate to Outdoor Temperature on a Balance Point Graph?
The balance point graph gives the relationship between the heating capacity of a heat pump against the heating load of a building with respect to outdoor temperatures.
- Heat Pump Capacity Curve. A heat pump's heating output reduces with drops in outdoor temperatures. Manufacturers test at 47°F and 17°F to assess the degree of decline.
- Building Heating Load Curve. As outdoor temperatures drop, a building requires boosting of heat in order to restore room temperature that is comfortable. It is worth noting that heat dissipation rates under very cold conditions depend on insulation, window quality, and leakage rates.
- Balance Point Intersection. The balance point is the intersection of the curves. Above this temperature, the heat pump is providing more than enough heating. Below this temperature, supplemental heating will be needed.
Balance point Formula:
- C(T) = Heat pump capacity at T°F
- C47 = Heat capacity at 47°F
- C17 = Heat capacity at 17°F
- L design = Heating load at design temp. ( eg 10°F)
- T design = Design Temperature
- T indoor = Indoor set temperature (eg 70°F)
A heat pump balance point calculator will calculate the above formula for you. These are the entries to make:
-Heat pump capacity at 47°F (BTU/h)
-Heat pump capacity at 17°F (BTU/h)
-Final Building Heating Load (design temperature) (BTU/h)
-Design temperature (10°F, for example)
-Indoors setting temperature (70°F, for example)
The calculator determines the outdoor temperature where heat pump capacity equals heating load; this is referred to as the "balance point."
Significance of the Balance Point:
When you know the balance point at which your HVAC system operates:
1.You save energy:
Capitalize on energy spent with the efficient and convenient use of electric or other heating alternatives while relying primarily on the heat pump.
2.You increase the chances of correct sizing of the heating system.
Putting yourself off on oversized/undersized units that waste energy.
3.Optimize Comfort:
Set smart thermostats to go into auxiliary heating mode only when necessary.
Conclusion:
This is a temperature at which the air source heat pump will balance out its use with the need for auxiliary heating. Heat pump balance point calculators help homeowners improve energy savings to operate their heating systems more efficiently. This will all help in minimizing the cost of heating.
