15 amp fresh water pump with 10 AWG wire

[scross]

I know replacing the fresh water pump has been discussed many times before. Haven’t seen the answer to this question yet though.
On page 32 of the Cutwater 28 owners manual it says that the wiring to and from the fresh water pump (labeled Water Pressure) is Brown/Yellow 10. I’m assuming that the 10 means 10 AWG. The stock fresh water pump is a 10 Amp pump with a 10 Amp fuse on the PDP Fuse Block.
I would like to replace the 10 Amp stock water pump with a 15 Amp Johnson Pumps 10-13329-103 Flowmaster Variable Fresh Water Pump.
If the wiring to and from the water pump is actually 10 AWG then I should be fine to use the existing wiring, install a 15 Amp fuse at the PDP fuse block and be good to go. The Brown/Yellow 10 wire exiting the PDP fuse block is labeled Fresh Water Pump and seems to be 10 AWG as indicated in the Owners Manual.
Am I missing anything?

 

[Red Raven]

Hi Al,

You are not missing anything as long as the wire is actually 10 AWG. I personally would want to see 10 written on the wire sleeve before proceeding and not rely on the owners manual. I don’t recall wires to the pump on our boat of 10 AWG. The gauge should be written on the wire jacket somewhere. That said, even 12 gauge wire may be fine for a 15 amp pump with a total run length of less than 12.5 feet (25 feet round trip). The pump should not be that sensitive to a voltage drop of less than 10% and a 15A fuse is more than adequate fire protection for 12 gauge wire.

Curt

 

[Brian John]

One consideration beyond the amperage of the #10 AWG, is the Voltage Drop (VD), I am assuming the pump is 12 VDC?

If so check the VD based on the actual amperage and conductor length here.

https://www.calculator.net/voltage-drop-calculator.html