I think that there are two ways to resolve this problem:

1. You can trying overwrite DecimalPipe from @angular/common library:

In this way:

point-replacer.pipe.ts

import { Pipe } from '@angular/core';
import {DecimalPipe} from "@angular/common";

@Pipe({
    name: 'pointReplacer'
})
export class PointReplacerPipe extends DecimalPipe {

  transform(value: any, digits?: string): string {
        return super.transform(value, digits).replace(',', '.');


    }
}

and in your html code:

<div padding *ngIf="TotalAPagar">
    $ {{TotalAPagar | pointReplacer }}  
</div>

2. You can write your own pipe, which replaces characters and use **double pipe in your html code**

Try in this way:

point-replacer.pipe.ts

import { Pipe, PipeTransform } from '@angular/core';

@Pipe({
    name: 'pointReplacer'
})

export class PointReplacerPipe implements PipeTransform {
    transform(value: string, args: any[]): string {
        if(value) {
          return value.replace(',', '.');
        }
        return '';
    }
}

and in your html code:

<div padding *ngIf="TotalAPagar">
    $ {{TotalAPagar | number | pointReplacer }}  
</div>

No matter which method you choose, don't forget to declare your own pipe in module, where you use it:

@NgModule({
  declarations: [PointReplacerPipe],
  providers: [PointReplacerPipe]
}) 

​After reading in forums and docs about angular js y javascript i found a method that puts the numbers in format and currency, that method is toLocaleString(), is a method from javascript that helps to put it in the currency or languaje that you need.

i search the name of the country that i need with the method and show me the info that need about. (http://www.localeplanet.com/icu/es-CO/), In my case was colombia.

in my functions i just have to add the .toLocaleString('es-CO') to the result and put the value with the specified currency.

for example:

this.TotalAPagar = (this.calcularDescuentosLiquidacion(this.TotalDevengadoValor, this.sueldoPendientePorCancelarValor, this.item.libranza, this.item.prestamo_empleado)+ this.calcularIndemnizacion(this.item.promedio_salario, this.item.fecha_fin_contrato, this.item.fecha_inicio_contrato)).toLocaleString('es-CO');

I think that this is a cleaner solution:

Import LOCALE_ID in app.modules.ts

import {ErrorHandler, NgModule, LOCALE_ID} from '@angular/core';

and define in providers like this:

  providers: [
    PouchServiceProvider,
    DbProvider, {
      provide: LOCALE_ID,
      useValue: "nl-NL"
    }
  ]

this will auto choose the seperator id, based on local_id