Air conditioning installation

[Honch]

I am replacing the original 16k btu Marine Air unit in the salon with a new Dometic. It is a perfect replacement with all dimensions making it an easy swap. All that is left is the wiring. The original unit had four wires, one green two brown wires and a blue wire. The new unit has places for an additional wire, but as I remember reading from the old Grand Banks Forum that it is simple to wire(that forum is down).View attachment 105433
If anyone has experience with this, I would appreciate your input.
Bob

 

[STB]

What is the model of the new unit? Is it 115V or 230V

Normally, there will be three power wires coming in, either L1-L2-GND or L1-N-GND.
Then, there will be three wires going out to the pump, probably with the same configuration as the wiring coming in. The blower and compressor are usually wired internally. The temperature sensor is usually connected inside and run to the return.
The control panel, which usually connects via a telephone-style cord.

Looking at that picture, I think I see the L1, L2 and GROUND incoming connections. If this is a 230V unit, that L2 is L2, if not it is Neutral.

L1-Pump and L2-Pump look to be the switched L1 and L2 electrical output to the pump.
L1-Fan and L2-Fan look to be the switched L1 and L2 electrical output to the fan/blower.
L1-comp and L2-comp look to be the switched outputs to the compressor.
They all share GROUND one way or another.

If you can pass along the model of the new unit, and if you have it the old unit, I can take a look for online manuals.

Alternatively, you've got the wiring diagrams for each. They are usually on or in the controller box. Match up the wires on each and you'll know how to connect them.

 

[Honch]

The new unit is a 120 v turbo 16k Dometic.
DTG16-1171-410A turbo. The wires for the fan, comp and valve are already connected from the factory. It is just the Others I am not sure of.
Thanks for any help.

 

[LarryM]

Sounds like your Grand Banks might be wired according to European & New UK standards.

Wire Color Codes in Europe (IEC) for AC supply are as follows:

Single Phase, Line (Hot) – Brown
3 Phase, Line 1 – Brown
3 Phase, Line 2 – Black
3 Phase, Line 3 – Grey
Neutral – Blue
Ground – Green or Green with Yellow Stripe

Here's a link to these wiring colors you might find useful.

So, applying these standards to the new system, the Single Phase A/C wiring circuit from the breaker panel should be:
L1 = Brown
L2 = Blue
Gnd = Green

The wiring to the raw water pump should be:

L1 Pump = Black or Brown
L2 Pump = White or Blue
Gnd = Green

This should be relatively easy to check with a multimeter. The confusion comes from the second brown wire you mention.

Are both brown wires the same gauge? The L1 and L2 wires should be the same gauge.

Refer to gkesden's clear and accurate explanation of the standard wiring for modern marine air conditioning systems.

Hopefully this gets you pointed in the right direction, but that's all I can suggest without more info.