**Heat of Extraction Training**
**Introduction**
Today we're going to be talking about heat of extraction. This is a very important diagnostic tool that we can use to quickly and easily check the performance of our geothermal units. We'll cover the basics of heat of extraction, how to calculate it, and some examples of how to use it to troubleshoot problems.
**What is Heat of Extraction?**
Heat of extraction is the amount of heat that is removed from the home by the geothermal unit. This heat is then used to heat the water in the loop field. The amount of heat that is extracted is determined by the following factors:
* The temperature of the water entering the unit
* The temperature of the water leaving the unit
* The flow rate of the water through the unit
* The brine factor (the specific heat capacity of the fluid in the loop field)
**Calculating Heat of Extraction**
The formula for calculating heat of extraction is:
```
Heat of Extraction = (Temperature Difference * GPM * Brine Factor)
```
Where:
* Temperature Difference = The difference between the entering and leaving water temperatures
* GPM = The flow rate of the water through the unit
* Brine Factor = The specific heat capacity of the fluid in the loop field
**Example**
Let's say we have a geothermal unit with a 40 degree entering water temperature, a 30 degree leaving water temperature, a 9 gpm flow rate, and a brine factor of 485.
```
Heat of Extraction = (40 - 30) * 9 * 485 = 38,848 BTU/hr
```
**Using Heat of Extraction to Troubleshoot Problems**
One of the best things about heat of extraction is that it can be used to troubleshoot problems with geothermal units. If the heat of extraction is lower than what is listed in the unit's specifications, it could indicate a problem with the unit.
Here are some common problems that can cause a lower heat of extraction:
* **Insufficient water flow**. If the water flow through the unit is too low, the unit will not be able to extract as much heat from the home.
* **Incorrect brine factor**. If the brine factor is incorrect, the heat of extraction calculation will be incorrect.
* **Faulty sensors**. If the sensors on the unit are not working properly, they could be giving inaccurate readings, which could lead to an incorrect heat of extraction calculation.
**Conclusion**
Heat of extraction is a valuable diagnostic tool that can be used to quickly and easily check the performance of geothermal units. By following the steps in this guide, you can troubleshoot problems with your geothermal unit and get it back up and running in no time.
