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AAP817 - Heater Matrix – Downward-Facing Pipes

Original price - Original price €63,50
Original price
€63,50
€63,50 - €63,50
Current price €63,50
Aftermarket Part
Aftermarket: Quality alternative. This is a quality alternative, designed to fit and function like the original part, often at a more competitive price.
Heater Matrix is the compact coolant-to-air heat exchanger at the core of the cabin heating circuit, housed within the heater box behind the dashboard.

Engine coolant is circulated through the matrix while the blower motor forces cabin air across its finned core, transferring heat into the passenger compartment. This version is configured with downward-facing inlet and outlet pipe stubs and is intended for heater assemblies without air conditioning.

With age the core can corrode internally or weep at the pipe unions, reducing heat output or allowing coolant to enter the footwell. Fitting a new matrix restores full cabin heating performance.
Vehicle Model Land Rover Defender up to 2016
Fitment Notes DEFENDER 1987-2006 — Heater matrix with downward-facing pipes, to VIN WA159806, non-AC; 2.5L 200TDi/300TDi diesel, petrol
Alternative Codes
AAP817AAP817RBR 1347

In stock 3 units
2 · Gouda 1 · Drachten
Express delivery available

When will my order arrive?
  • Order before 15:00 (Mon–Fri): same-day dispatch for in-stock items.
  • UPS Express (order before 14:00): dispatched today, delivered tomorrow where available.
  • Netherlands / Belgium / Germany: 2–4 working days.
  • Other EU countries + UK: 4–8 working days.
  • Outside EU/UK: delivery times vary — contact us for an estimate.

Items may ship from multiple warehouses at no extra cost.

Job kits containing this part

This part is included in 0 job kit(s) below. Pick the kit that matches your vehicle and job, then add what you need.

Frequently asked questions

What does the heater matrix do on a Defender?
The heater matrix is a small coolant-to-air heat exchanger inside the heater box behind the dash. Hot engine coolant passes through it while the blower fan pushes cabin air across its fins, warming the interior. On a Defender it's the core of the cabin heating system.
What's the difference between the downward-facing and upward-facing pipe heater matrix?
This heater matrix has downward-facing inlet and outlet pipe stubs, which sets how it plumbs into the heater box. Land Rover used more than one pipe orientation, so match the pipe direction to your existing unit. This version is for heater assemblies without air conditioning.
Which Defenders does this heater matrix fit?
This heater matrix fits the Land Rover Defender 1987-2006 up to VIN WA159806, non-AC models, with 2.5L 200TDi and 300TDi diesel and petrol engines. Check your VIN against WA159806, as later vehicles use a different matrix.
Why do Land Rover heater matrixes fail?
Heater matrixes typically fail as the core corrodes internally or weeps at the pipe unions with age. Symptoms include weak cabin heat, a sweet coolant smell, misted windows, or coolant in the passenger footwell. Fitting a new matrix restores full heating.
How hard is it to replace a Defender heater matrix?
Replacing the heater matrix is typically an involved job, as it sits inside the heater box behind the dashboard and the cooling system must be drained first. Many owners find it a specialist task. Fresh coolant and a check of the pipe unions are usually needed on refit.