When installing your Propex heater, it is important to follow some specific guidelines when routing your combustion pipes. Failure to heed this guidelines can cause irregular operation and fault codes.

• The golden rule when installing your heater is that you should not shorten your combustion pipes under any circumstances. The heater is engineered to operate under very specific air flow parameters and shortening the pipes WILL lead to improper or failed combustion and a four-flash fault code.

• You can lengthen your combustion pipes up to 1.5 meters if absolutely necessary however this can also lead to air flow issues. If you find that your build requires a run of longer that 1.5 meters, consider choosing a different location for installation.

• Pipes should be mounted so that their ends terminate at least .5 meters away from each other. It is imperative that the combustion intake does not suck in exhaust.

• The ends of the pipes when mounted should not face each other to prevent exhaust flowing into the intake.

• The pipes should never terminate in a boxed section of the vehicle frame. Always route them to the outside of the vehicle.

• Combustion pipes should be mounted with a slight downward slant away from the heater. This prevents any condensation from infiltrating the heater unit and fouling the internal components. Similarly, a downward slope will help drain any water that may get into the pipes from the environment.

• If you must route the combustion pipes under a chassis frame member, drill a 1mm hole in the bottom of the pipe at its lowest point to drain any water that gets in. The pipes should be as straight as possible.

• From the heater itself there should be as little vertical drop as possible. When installing the heater onto a thick insulated floor, it may be necessary to route the pipes vertically a few inches but try to minimize the length of this section. Vertical runs in the combustion pipes (specifically the exhaust pipe) can cause a 'chimney effect' that will slow the speed of the exhaust as the hot air tries to rise back into the heater. The fan typically can overcome this but we have seen instances where vertical runs can cause an air flow fault code.

• Keep the end caps on the ends of the combustion pipes to limit any debris or water intrusion. Let's face it, we install these in camping vehicles that see dusty roads, mud puddles, etc. The end caps prevent blocks in the pipes.

• If you have driven any water crossings or had copious amounts of water or mud that may have entered your combustion pipes, remove the pipes from the heater and blow them out with compressed air to clear them. Do NOT run your heater if you believe water has entered the pipes. Clean them out at your earliest convenience to prevent water and debris from entering the heater and damaging internal components.

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