MVHR Maintenance: the Essential Guide to Keeping Your System Running Smoothly
Congratulations on joining the growing number of homeowners enjoying the benefits of a Mechanical Ventilation with Heat Recovery (MVHR) system. You've invested in technology that provides fresh, filtered air, recovers heat, and creates a healthier, more comfortable living environment. But like any sophisticated system, your MVHR unit needs a little TLC to keep it performing at its best.
Just like owning a car, regular checks and maintenance ensure it runs efficiently, reliably, and lasts for many years to come. Conversely, neglecting your MVHR system can lead to reduced efficiency, poor air quality, and even potential damage if left untreated. Let’s explore what you can do to get the very best in quality and longevity from your MVHR system.
Your DIY MVHR Maintenance Checklist
Much of the essential MVHR aftercare can be handled easily by you. Setting a regular schedule for these simple checks will make a significant difference to your system's efficiency and longevity.
Here’s your checklist for straightforward MVHR system maintenance:
1. Check and Change Your Filters (Every 3-6 Months)
This is arguably the most important DIY maintenance task. Your MVHR filters are the unsung heroes, trapping dust, pollen, and other pollutants before they enter your home. Over time, they get clogged, which restricts airflow and makes your system work harder (using more energy).
- How often? Check your filters every 3 months and replace them at least every 6 months. You may need to change them more often depending on your surroundings. Traffic and built-up urban areas will take their toll on filters, but floating pollen, pets and insects in rural areas can also increase filtered matter.
- How to check: Most MVHR units have easily accessible filter compartments. Simply slide out the old filters and hold them up to the light. If they look dirty or clogged, it's time for a change. Don't be tempted to wash or vacuum disposable filters – this can damage them and reduce their effectiveness. Always replace them with new, manufacturer-approved filters.
- Where to buy: You can easily purchase replacement filters directly from us. Ensuring you use the correct type (check your system manual or the label on the old filter) is crucial for performance and warranty.
Ordering your replacement MVHR filters with 21 Degrees is easy.
2. Clean Supply and Extract Grilles (Every 6-12 Months)
The grilles (or valves) on your ceilings or walls are where the fresh air enters, and stale air leaves your rooms. Dust and grime can build up on or around these over time, looking unsightly and potentially hindering airflow.
- How to: Gently wipe the grilles with a damp cloth. Dust around them if there is a ring of dust on the ceiling (note this is dust already in the room being caught in the airflow not dust being introduced by the MVHR system).
3. Check External Vents (Annually)
Your MVHR system has terminals on the outside of your house where fresh air is drawn in and stale air is expelled.
- What to look for: Ensure these vents are clear of obstructions like leaves, cobwebs, debris, or vegetation. Blocked vents severely affect performance.
A printable MVHR maintenance checklist can be found here, handy to keep alongside your MVHR unit for reference and easy filter ordering.
MVHR Troubleshooting FAQs
Even well-maintained systems can sometimes throw a curveball. Here are answers to some common questions:
"My Mvhr System is Making a Strange Noise – What Do I Do?"
First, check if it's filter change time – clogged filters can cause the unit to work harder and become noisier. Also, check that room grilles haven't been accidentally adjusted or knocked. If the noise is a persistent hum or whirr, but liveable with, it' best to leave the unit on but call us to arrange a service. Should it be a more worrying grinding or rattling noise, then turn the unit off. If you have turned the system off, then consider naturally ventilating by opening windows.
"Can I Turn Off My Mvhr When I Go on Holiday?"
It's generally recommended never to turn off your MVHR system when you're away. It uses very little energy on low settings and ensures your home stays ventilated, preventing moisture build-up and stale air which can lead to mould growth in ducts while you're gone. Most systems have a "holiday" or "away" mode to ensure minimal power requirements.
"My Filters Look Clean – Do I Still Need to Change Them?"
Yes. Filters trap microscopic particles that aren't always visible. Sticking to the recommended 6-month replacement schedule (or sooner if needed) ensures optimal air quality and system efficiency, even if the filters don't look completely dirty.
"Will I Void My Warranty if I Service the Basic Parts Myself?"
Performing the basic maintenance outlined above (filter changes, grille cleaning, visual checks) will generally not void your warranty. However, trying more complex internal repairs or using non-approved filters might. Always refer to your manufacturer's warranty documentation. Professional servicing (see below) is often a warranty requirement.
"My Machine Turned Off and Won't Turn Back on. What Do I Do?"
Check your home's main fuse box first to see if a circuit breaker has tripped. Check if the unit's isolator switch has been accidentally turned off. Some units have internal fuses or fault indicators – consult your manual. If these checks don't resolve the issue, contact a qualified service engineer.
When to Call the Professionals: 21 Degrees MVHR Servicing
While DIY checks are vital, professional servicing is essential for the long-term health and efficiency of your MVHR system.
How Often Should an Mvhr System Be Professional Serviced?
We recommend a professional service every year, or as specified by the manufacturer. This is often needed to maintain the warranty.
Why Does an MVHR system Need Professionally Serviced?
Trained engineers perform deeper checks beyond the scope of DIY maintenance.
What to Expect From a Professional MVHR Service Visit.
During a 21 Degrees service visit, our engineers typically:
- Replace filters (if not recently done).
- Clean the heat exchanger core.
- Inspect and clean fans.
- Check condensate drains and traps.
- Inspect all internal components and seals.
- Check ductwork connections and integrity (where accessible).
- Measure airflow rates to ensure the system is balanced and performing correctly (re-commissioning if necessary).
- Test controls and settings.
- Provide a full report on the system's condition.
Regular professional servicing ensures your system runs at peak efficiency, maximises heat recovery, keeps the air quality at its best, prolongs the unit's lifespan, and upholds your warranty.
Keep Your System Healthy With 21 Degrees
Looking after your MVHR system doesn't have to be complicated. By following the simple DIY checks and scheduling regular professional servicing with 21 Degrees, you ensure years of efficient operation, fresh air, and comfortable living.
Ready to book your professional MVHR service or need advice?
