Module 8 – When to Replace
Part of the Purus Lumina Device Care Education Programme
Cleaning maintains the device. Replacement is what sustains it.
The cleaning and maintenance protocol documented in Modules 2 and 3 is the foundation of device care. But cleaning has a limit. Components degrade. Seals harden and crack. Screens block beyond recovery. Mouthpieces accumulate residue that isopropanol cannot fully remove. At some point, the correct action is not to clean again — it is to replace.
No manufacturer of prescribed dry herb devices publishes a documented replacement schedule in the context of prescribed CBPM use. This module is that schedule. It is derived from the same principles that govern the cleaning protocol: a contaminated or degraded device does not deliver the prescription as intended, and the patient bears the consequences.
The principle of replacement
A component should be replaced when any of the following apply:
- Cleaning no longer restores it to a condition that meets the care standard
- It shows physical damage — cracks, deformation, tears, or corrosion
- It shows permanent discolouration that cleaning does not resolve
- It is past the manufacturer's recommended replacement interval, where one exists
- It is in any doubt — if you are uncertain whether a component is fit for use, it is not
The last point is the most important. A patient who uses a component they are uncertain about has made a clinical decision without clinical authority. The standard is: if in doubt, replace it.
Screens
The Mighty Medic+ uses two screens: a fine mesh screen at the base of the filling chamber and a regular screen in the cooling unit. Both are critical to device function. Both accumulate residue with every session.
When to replace: Replace either screen when cleaning does not restore full airflow through the mesh, when the mesh shows physical damage or deformation, or when residue is visible after a full clean. Do not attempt to use a damaged screen. A compromised screen alters the airpath and the dose delivered.
Replacement interval: For moderate use (3–5 sessions daily), inspect screens after every clean and replace at least every 4–6 weeks. For heavy use (6+ sessions daily), inspect after every clean and replace every 2–3 weeks. For light use, replace at least every 8 weeks regardless of appearance.
Storz & Bickel guidance: Replacement screens are available directly from Storz & Bickel. Keep a stock of both screen types. Running out of replacement screens is not a reason to continue using a degraded screen.
Seals and O-rings
The Mighty Medic+ contains multiple seals and O-rings that maintain the integrity of the airpath. These components are subject to repeated heat cycles, isopropanol exposure during cleaning, and mechanical stress from assembly and disassembly. They degrade over time regardless of how carefully the device is maintained.
When to replace: Replace any seal or O-ring that shows cracking, hardening, deformation, or loss of elasticity. A seal that no longer seats correctly is not a functional seal. Replace immediately — do not use the device with a compromised seal.
Replacement interval: Storz & Bickel recommends replacing the wear set (seals, O-rings, and screens) every 3 months for regular use. For high-frequency clinical use, this interval should be reduced. A patient using the device 6+ times daily should treat the 3-month interval as a maximum, not a target.
The wear set: Storz & Bickel supplies a wear set containing all seals, O-rings, and screens as a single replacement unit. Ordering and replacing the full wear set at the recommended interval is the correct standard — not replacing individual components as they visibly fail.
The cooling unit
The cooling unit is the component most exposed to vapour residue. It is the primary accumulation point for cannabinoid oils, terpene residue, and combustion byproducts. It is also the component most frequently cleaned — and therefore the component most subject to mechanical wear from repeated disassembly.
When to replace: Replace the cooling unit when cleaning no longer removes residue from the internal channels, when the plastic shows permanent discolouration or deformation, when the mouthpiece connection shows wear that affects the seal, or when the unit has been dropped and shows any structural damage.
Replacement interval: For moderate to heavy use, the cooling unit should be replaced every 6–12 months. A cooling unit that has been in daily use for over a year and has never been replaced is not operating to the standard of a new unit, regardless of how well it has been maintained.
The mouthpiece
The mouthpiece is the final contact point between the device and the patient. It is also the component most exposed to saliva, ambient contamination, and handling. In a shared device context — household use, carer-assisted use — the mouthpiece is the primary cross-contamination risk.
When to replace: Replace the mouthpiece when cleaning does not remove residue or discolouration, when the plastic shows cracking or deformation, or when it has been used by more than one person without replacement. In a shared device context, each user should have their own mouthpiece.
Replacement interval: For sole-user devices, replace every 3–6 months. For shared devices, replace each user's mouthpiece every 3 months or sooner if the care standard cannot be maintained.
Dosing capsules and accessories
Replacement schedules for dosing capsules, grinder (Herbing Mill) screens, and filling set components are documented in Module 6. The principle is the same: replace when cleaning no longer works, when physical damage is present, or when the component is in any doubt.
When to replace the device itself
The device as a whole should be considered for replacement when:
- It has been in use beyond the manufacturer's warranty period and shows performance degradation that component replacement does not resolve
- The heating element shows inconsistent temperature performance — sessions that do not reach the set temperature, or that overshoot it
- The battery no longer holds sufficient charge to complete a full session at the prescribed temperature
- Physical damage has compromised the structural integrity of the device body
- The device has been dropped, submerged, or exposed to conditions that may have affected the electronics
Warranty and replacement: The Mighty Medic+ carries a 3-year warranty when registered with Storz & Bickel. Patients who have not registered their device should do so immediately — registration is free and the warranty period runs from the date of purchase, not the date of registration. A device that fails within the warranty period should be returned to Storz & Bickel for assessment before the patient purchases a replacement.
Clinic-supplied devices: Patients whose device was supplied by a clinic or funding scheme should contact the supplying clinic or scheme operator before purchasing a replacement. The supply obligation may extend to replacement in certain circumstances. This curriculum documents that no clinic currently advises patients of this — it should be standard practice.
Replacement schedule summary
- Screens (both): Every 2–8 weeks depending on use frequency. Inspect after every clean.
- Full wear set (seals, O-rings, screens): Every 3 months for regular use. Every 6–8 weeks for heavy use.
- Cooling unit: Every 6–12 months for moderate to heavy use.
- Mouthpiece: Every 3–6 months. Immediately if shared.
- Dosing capsules: When cleaning no longer works or physical damage is present.
- Grinder (Herbing Mill) screen: When cleaning does not restore mesh airflow.
- Device: When performance degradation cannot be resolved by component replacement, or at end of warranty life.
In plain terms
Cleaning keeps the device functional. Replacement is what keeps it safe. The two are not alternatives — they are sequential. When cleaning stops working, replacement is the only correct response.
Keep a stock of replacement screens and a wear set. Order them before you need them. A patient who cannot use their device because they are waiting for replacement parts has a gap in their prescription delivery. That gap is preventable.
If the device is in any doubt — do not use it. Replace the component. If the device itself is in doubt — contact Storz & Bickel and your prescribing clinic before your next session.
Notice of Intent
This curriculum has been submitted to the MHRA, Home Office, NHS England, NICE, the Care Quality Commission, relevant parliamentary and clinical bodies, and device manufacturers operating within the UK prescribed CBPM pathway, as a formal educational contribution to a documented gap in patient care. It is published in perpetuity as a matter of public record. Purus Lumina reserves all rights to the curriculum structure, content, and methodology.
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Module 8 is part of the Purus Lumina Device Care Curriculum — the world's first documented device care education programme for patients prescribed botanical medicine. Published as a matter of public record. Preserved in perpetuity.
This module was published on 4 July 2026 and exists in perpetuity as part of the Purus Lumina Device Care Curriculum — the world's first documented device care education programme for patients prescribed botanical medicine. It will not be removed.
Glenn Hailes · Director · Purus Lumina Ltd · 3rd Floor, 86–90 Paul Street · London EC2A 4NE · United Kingdom · Registered in England and Wales