Thermal Needle Probe measurement Thermal Needle Probe measurement
Thermal needle probe measurements are used to measure ground conductivity at shallow depths.
Thermal needle probe measurements are used to measure ground conductivity at shallow depths.
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What is a Needle Probe Measurement?
A needle probe measurement is a testing method used to work out the thermal conductivity of the ground at shallow depths. It’s often used when a horizontal ground loop is being used for a ground source heat pump system.
It is very useful during the early design phase of a system. It provides important data to inform the size and layout of horizontal ground collectors.
How It Works:
- The ground is lightly augured (bored) by a technician to create access at specific depths.
- A thermal needle probe, which contains both a heating element and a temperature sensor, is placed into the soil.
- The probe applies a controlled amount of heat and records how the temperature changes.
- This data is studied using thermal equations to calculate the soil’s thermal conductivity.
- Multiple readings may be taken across the site to improve accuracy. The results are combined to produce a geometric mean thermal conductivity value.
Why It’s Useful:
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Non-invasive and low-cost. It’s ideal for small to mid-scale projects.
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Helps ensure the horizontal ground array is the correct size and spaced well.
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Predicts system efficiency and long-term performance.
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Quicker and simpler than full-scale Thermal Response Testing. This is especially true when boreholes are not planned.
When Is It Used?
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On sites proposing horizontal ground loops for GSHP systems.
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When shallow ground conditions need to be assessed.
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During feasibility studies or preliminary design stages.
Needle probe testing gives designers and installers like Geowarmth a reliable understanding of local ground conditions. It ensures efficient, well-sized systems with reduced design risk.
Contact Us
If you’re unsure what’s right for your home or business, get in touch today
Contact Us
If you’re unsure what’s right for your home or business, get in touch today