Step-by-Step Guide: How to Install a 90cm Cooker Hood for Optimal Kitchen Ventilation

A powerful and efficient cooker hood is essential for maintaining a fresh, clean, and comfortable kitchen environment, especially for those with larger hobs. If you've chosen a 90cm cooker hood for its superior coverage and extraction capabilities, the next crucial step is proper installation. While it might seem daunting, with the right tools, careful planning, and adherence to safety guidelines, you can successfully install a 90cm cooker hood and transform your culinary space.

This guide provides a comprehensive, step-by-step approach to installing a 90cm cooker hood, ensuring safety, efficiency, and longevity.

Before You Begin: Preparation is Key

Before you even touch a tool, thorough preparation is paramount. This is especially true for a larger appliance like a 90cm cooker hood.

1. Read the Manufacturer's Instructions: This is the most critical step. Every cooker hood model has specific requirements and instructions. The information provided here is general; always defer to your hood's manual for precise measurements, mounting methods, and electrical specifications.

2. Safety First:

• Disconnect Power: Absolutely crucial. Turn off the electricity supply to the kitchen circuit at your main consumer unit (fuse box) before touching any wiring. Use a voltage tester to confirm the power is off.

• Protective Gear: Wear safety glasses and gloves.

• Assistance: A 90cm cooker hood can be heavy and awkward. Enlist the help of another person for lifting and holding, especially during mounting.

• Pencil, measuring tape, spirit level

• Drill with appropriate bits (masonry bits for brick walls, wood bits for studs)

• Screwdriver set

• Adjustable spanner/wrench

• Wire strippers/cutters

• Duct tape or aluminium foil tape (for sealing ducts)

• Jigsaw or hole saw (for cutting cabinet/wall openings, if required)

• Wall plugs/anchors suitable for your wall type (often supplied, but check quality)

• Silicone sealant (for sealing ducting to exterior wall)

• Ladder or step stool

• Ducted: Requires an existing or new exterior vent hole and appropriate ducting (usually 150mm diameter for optimal 90cm hood performance).

• Recirculating: Requires charcoal filters (usually sold separately) and no exterior vent.
  The installation steps for ducting will be covered.

Step-by-Step Installation Process

Phase 1: Planning and Marking

1. Determine Hood Height: Refer to your manual for the recommended distance between your hob and the bottom of the cooker hood. This is typically 65-75 cm for electric hobs and 70-80 cm for gas hobs. Mark this minimum height on the wall above your hob.

2. Locate Mounting Points:

• Measure the width of your 90cm cooker hood and mark the center point above your hob.

• Using the template provided by the manufacturer (if available) or by carefully measuring the mounting holes on the hood itself, mark the exact drilling points on the wall. Use a spirit level to ensure these marks are perfectly horizontal.

• If installing a chimney hood, also mark the top mounting points for the chimney extension.

• If you need to cut a new hole for the ducting, mark its exact position and size (typically 150mm diameter for optimal airflow with a 90cm hood). This is usually directly above the hood's outlet, extending through the wall to the outside.

Phase 2: Drilling and Mounting Brackets

1. Drill Mounting Holes: Using the appropriate drill bit for your wall type (masonry for brick, wood for studs), carefully drill the marked holes. Ensure the depth is sufficient for the wall plugs.

2. Insert Wall Plugs/Anchors: Insert the appropriate wall plugs into the drilled holes. Tap them flush with the wall surface.

3. Mount Support Brackets: Secure the hood's main support bracket(s) to the wall using the screws provided (or suitable heavy-duty screws if the wall type requires it). Use a spirit level to ensure they are perfectly straight. For chimney hoods, also install the upper chimney bracket.

Phase 3: Ducting Installation (if ducted)

1. Cut Ducting Hole (if new): If you're cutting a new hole for the ducting, use a hole saw or jigsaw. Exercise extreme caution and ensure you don't damage any hidden pipes or wiring.

2. Install Ducting:

• Attach the ducting adapter to the hood's outlet.

• Run the ducting (rigid or flexible) from the hood's outlet through the wall hole to the outside. Keep the ducting as straight and short as possible, with minimal bends, to maximize efficiency and minimize noise.

• Secure all ducting joints with duct tape or aluminium foil tape to prevent air leaks.

• Install an external vent cover (e.g., a cowl) on the outside wall to prevent pests and weather ingress. Seal around the cowl with silicone sealant.

Phase 4: Mounting the Hood Body

1. Lift and Mount: With the help of your assistant, carefully lift the 90cm cooker hood and hang it securely onto the installed wall brackets. Ensure it slots firmly into place.

2. Secure the Hood: Fasten any additional securing screws at the bottom or sides of the hood as indicated in the manual to prevent movement.

Phase 5: Electrical Connection

1. Wire Connection: With the power still off at the consumer unit, connect the hood's electrical wiring to your kitchen's power supply. This usually involves connecting Live, Neutral, and Earth wires. If you are unsure, always consult a qualified electrician. Incorrect wiring can be dangerous.

2. Secure Wiring: Ensure all connections are secure and properly insulated.

Phase 6: Final Touches

1. Install Filters: Insert the metallic grease filters into their designated slots. If using a recirculating hood, install the charcoal filters now.

2. Install Chimney Sections (if applicable): Slide the decorative chimney sections into place, securing them to the upper chimney bracket and the hood body as per the manual.

3. Test the Hood: Once all steps are complete and the hood is securely mounted, turn the electricity supply back on at the consumer unit. Test all fan speeds and the lighting to ensure everything is functioning correctly.

4. Clean Up: Remove any debris, dust, or protective films from the hood.

Troubleshooting Common Issues

• No Power: Check circuit breaker, wall switch, and wiring connections.

• Poor Extraction: Check ducting for kinks or blockages, ensure filters are clean, and verify the external vent isn't obstructed.

• Excessive Noise: Could be loose parts, incorrect ducting size/installation, or obstructions in the fan.

By meticulously following these steps, you can successfully install a 90cm cooker hood, ensuring years of fresh, clean, and comfortable cooking in your kitchen. Remember, when in doubt, especially with electrical work or complex ducting, it is always advisable to consult a professional.