Good Question.However, the fused circuit modification you suggest should NOT be undertaken.
Reason - you will negate the recommended fuse rating for all the wiring and components that they relate to.
The 20A fuse is required to correctly protect the higher current (ampere) consuming heater unit ie, the heater internal combustion motor, glowpin and larger cross section cables powering the heater.
The 5A fuse is lower rated to protect the heater controller and small cross section cables utilised in that circuit.
Please keep these two fused circuits separated as shown in the electrical circuit diagram attached.
Any further questions, please call 01522 243310 or email sales@butlertechnik.com
Thank you
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