Problem with encoding (display wrog characters)

Server: PostgreSQL 9.3.5 on FreeBSD 10.0
Client: pgAdmin4 v3.4 on Windows 7 Profesional 64 bits

The database is LATIN1, when I run the next query

SELECT nom_usr FROM public.usuarios WHERE id_usr = 8;

in psql (in the server), it is displayed correctly

ACUÑA AARON

But in pgAdmin the display is wrong (Ñ is converted to 2 characters)

ACUÑA AARON

When I consult the encoding inside of pgAdmin with

SHOW client_encoding;

It shows

UNICODE

If I run the next command in a consult in pgAdmin

SET client_encoding = 'LATIN1';
SELECT * FROM public.usuarios WHERE id_usr = 8;

It display correctly

ACUÑA AARON

Is python assuming that because the database is in LATIN1, the
character arrive in LATIN1?

Any ideas about what is happening?

--
Martin Paredes
Hermosillo, Son. Mexico