The short answer
Both LD5 and LD7 list sensitivity of 0.05 oz/year for R-134a and 0.0123 oz/year for R-1234yf. LD7 adds a sweep display mode and UV LEDs to its electronic detection features. Choose by the inspection methods you use rather than assuming that the premium model has a lower listed detection threshold.
LD5 and LD7 at a glance
Both models combine a graphic display with an audible alert. The key buying question is whether the LD7's additional display and UV features are useful in your workflow.
| Feature | LD5 | LD7 |
|---|---|---|
| R-134a sensitivity | 0.05 oz/year | 0.05 oz/year |
| R-1234yf sensitivity | 0.0123 oz/year | 0.0123 oz/year |
| Graphic bar mode | Yes | Yes |
| Sweep line-graph mode | Not listed | Yes |
| UV LEDs | Not listed | Yes |
| Inspection light | Yes | Yes |
| Power | 4 AA alkaline batteries | 4 AA alkaline batteries |
LD5
Robinair Select Refrigerant Leak Detector
View specifications and current price →
LD7
Robinair Premium Refrigerant Leak Detector
View specifications and current price →When to compare LD5
The LD5 provides a bar-style graphic display, audible alerts and an inspection light. Compare it when those electronic inspection features cover the task and you do not need the LD7's additional modes in the same tool.
When to compare LD7
The LD7 adds a sweep line graph for observing detection changes and UV lighting for compatible dye inspection. Consider it when you want these methods together rather than using separate tools. UV inspection and electronic sensing are distinct methods; a UV light does not introduce dye into a system.
Choose a detector around your inspection method
- Identify the refrigerant. Match the detector to the exact refrigerant and application. Compatibility with R-134a and R-1234yf should not be treated as approval for every substance.
- Choose the feedback you need. Compare the display modes and sound indications with how you inspect equipment. An additional display mode is a workflow feature, not proof of higher sensitivity.
- Decide whether UV belongs in the tool. If dye inspection is part of the approved service process, assess whether integrated UV lighting helps. Confirm the system's dye requirements independently.
- Check consumables and included items. Review the supplied filters, batteries, test vial and case on the product listing. Confirm replacement-part compatibility before ordering spares.
- Plan for verification and maintenance. Follow the operating instructions for sensor checks, filter condition and use. The comparison table cannot establish whether a particular system is leak-free.
A useful way to make the choice is to list your must-have functions, then compare the current delivered price of each tool. If the LD5 covers the required method, extra features may not change the job. If you regularly switch between electronic and UV inspection, the LD7 is worth comparing for convenience.
Browse leak detection equipment for the current selection, or ask about the exact model and included kit.
Common leak-detector questions
Is LD7 more sensitive than LD5?
The manufacturer lists the same R-134a and R-1234yf sensitivity figures for both. The differences highlighted here are the sweep display and UV lighting.
Does LD5 support R-1234yf?
Robinair lists R-1234yf and R-134a compatibility for LD5. Check the operating instructions for the exact application and inspection procedure.
Does LD7 UV lighting replace electronic detection?
They are separate methods. UV lighting is used with compatible dye inspection; the electronic sensor detects supported refrigerant. Choose and apply the method required by the service procedure.
Does a detector repair a leak or recharge the system?
No. These are inspection tools. Repair and subsequent service require the appropriate procedures and equipment.
Specifications and scope
Prepared from Robinair LD5 Select and LD7 Premium product specifications, checked September 26, 2026. This is a buying comparison, not a hands-on test or operating procedure. Confirm the exact model and follow its operating manual. Current prices and availability appear on the product pages; see our delivery information and store warranty for purchase terms.
