In the West Island, HVAC systems are often found in tight spaces: between a sagging vinyl siding, an outdoor electrical box, and a cedar hedge that has grown faster than expected. This is exactly the scenario we encountered in Pointe-Claire , during a call about an LG wall-mounted heat pump ( mini-split type) whose efficiency had clearly decreased.
The customer described typical symptoms: less consistent heating , longer cycles, and the impression that the unit was working harder than before. Outside, the LG condensing unit was mounted on wall brackets , a few inches from a dense hedge. The refrigerant lines were visible, and a portion of the insulation on the piping appeared worn/damaged , which is often an important diagnostic clue.
Our mission: to restore stable, safe, and sustainable performance, without improvisation. As always, we followed a comprehensive diagnostic process before any intervention.
Context: a compact… and demanding residential installation
The photo shows a configuration that is very common in Greater Montreal:
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LG compact outdoor unit (mini-split)
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Installation on wall brackets (to avoid direct contact with the ground and snow)
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Wall-mounted electrical disconnect switch nearby
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Exposed refrigerant lines with insulation
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Cedar hedge on the left, very close to the ventilation grille/area
This type of location works… until the day maintenance and the environment (vegetation, humidity, debris) begin to impair heat exchange and the stability of the system.
Machine type and model (LG consistency)
This is a wall-mounted heat pump (mini-split / wall unit) .
The exact model is not legible on the label from the image, but the unit does indeed correspond to an LG “Dual Inverter” (common residential range in Quebec), a format often installed for heating/cooling comfort with good modulation.
In this type of case, the important thing is not to “invent” a model number: it is to diagnose precisely what is preventing the unit from delivering its actual capacity .
The reported symptoms: when comfort becomes irregular
The customer told us:
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A less stable temperature in the main area
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A sensation of warm airflow when heating (or less cold when air conditioning, depending on the season)
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More frequent cycles, and sometimes a feeling of more noticeable noise/vibration
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Performance is better earlier in the day, then less efficient after several hours.
This portrait often corresponds to one (or a mixture) of the following elements:
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External heat exchange disrupted (obstructed ventilation, clogged coils)
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refrigerant charging problem (micro-leak, flare fitting)
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electrical component/control or probe that drifts
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Deteriorated line insulation leading to losses, condensation or localized icing
Step 1 — Visual inspection and environmental factors
Before opening anything, we carried out a complete inspection:
1) Air clearance around the outdoor unit
The cedar hedge is very close. On a heat pump, this is critical: the unit needs to breathe . When the return air supply is limited, the system compensates by increasing the compressor's workload, which can cause:
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actual capacity reduction
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longer cycles
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accelerated wear
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unstable behavior during defrosting (in winter)
2) Condition of refrigerant lines
A section of damaged insulation is visible on the pipe (the larger section, usually the suction line). Damaged insulation can:
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increase heat loss
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create condensation that drips and damages the envelope
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promote localized icing phenomena depending on the conditions
3) Wall mounts and vibrations
The supports seem adequate, but a wall-mounted installation can transmit vibrations if:
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the silent blocks are aging
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the piping touches a rigid element
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the fasteners were tightened too tightly
Step 2 — Technical diagnosis (the part that avoids “random repairs”)
Next, we moved on to the measured diagnosis:
Measurements and checks carried out
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Verification of the control and behavior (start-up, modulation, stability)
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Temperature readings (ambient air / supply air) to validate the difference
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Monitoring of pressures and consistency of the refrigeration cycle (depending on the season)
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Validation of parameters indicating a possible micro-leak (pressure/temperature trends, reaction to the operating regime)
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Targeted inspection of flare fittings / service valves (typical areas of slow leakage)
In this case, our diagnosis converged on a very common combination for outdoor mini-splits in vegetated environments:
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Ventilation partially obstructed by the proximity of the hedge + slight fouling of the coil
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Insulation degradation along the line increases losses and creates conditions for reduced efficiency.
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Suspected slightly faulty connection (micro-leak or minor loosening), to be confirmed and properly corrected.
Step 3 — Intervention: complete, clean and sustainable upgrade
A reliable repair isn't just about "adding gas" or "a quick clean-up." Therefore, we applied a comprehensive procedure.
1) Clearance and optimization of ventilation
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Safely clear the area around the unit (without damaging the hedge)
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Clear recommendation to the client on the minimum clearance to be maintained (incoming/outgoing air)
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Targeted cleaning of the external coil when required, to restore heat exchange
Immediate result: the system breathes better, and the modulation becomes more stable again.
2) Repair of line insulation
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Removal of damaged insulation sections
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Installation of new, suitable exterior insulation (UV/moisture resistant) and protection of sensitive areas
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Verification that the piping does not create a rigid contact point that could vibrate
It seems “simple”, but it is often this detail that prevents: losses, condensation, and recurring discomfort.
3) Correction of joints and sealing
When our tests confirm a doubt about a fitting, we apply a professional method:
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Check and correct the connections as needed (appropriate torque)
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Leak test (rigorous procedure)
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If the load needs to be adjusted: a clean, compliant, and measured approach, never blindly.
4) Performance tests
After the procedure:
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Extended operating test
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Validation of cycle stability
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Verification that the unit reaches the setpoint without "forcing" it
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Noise/vibration control and adjustments if necessary
Result: comfort restored, performance stabilized
After the upgrade:
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The customer has regained a stable temperature in the service area.
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The cycles became more regular, with better modulation
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The outdoor unit operates with healthier ventilation
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The piping is better protected, which improves the durability of the installation.
In short: an LG wall-mounted heat pump that starts delivering what it's supposed to deliver — without overconsumption, without unnecessary mechanical stress, and with significantly more consistent comfort.
Key takeaways (useful for many homes in Pointe-Claire and elsewhere)
Even an excellent heat pump can lose performance if:
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vegetation blocks the air
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The insulation on the lines is deteriorating.
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a fitting is starting to leak very slightly
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The maintenance of the coil is neglected
Our approach at AirGreen: comprehensive diagnosis, lasting fixes, and transparency . We don't "guess" — we measure, we confirm, then we repair properly.