source: http://blog.hekkers.net/2011/03/14/remeha-interface-revisited/
source: http://blog.hekkers.net/2010/10/03/monitoring-the-remeha-calenta/
source: http://www.barrydegraaff.tk/2012/11/remeha-recom-interface-simplified.html

Remeha is a USB connector with built-in FTDI chip. This cable can be very handy – if you don’t need Ethernet or don’t like soldering, this will probably be the easiest/best/quickest option for you.

The wireing is a 4p4c (RJ14) modular_connector:

In the photo the wireing is as follows:

1 – red – +5V
2 – yellow – RXD
3 – orange – TXD
4 – black – GND

Remeha Interface connector RC11 (4P4C) pinout
using 4p flatcable
# 1 Ground (Black)
# 2 Device RXD* (Red)
# 3 Device TXD* (Green)
# 4 VCC (5v) (Yellow)

FTDI USB/TLL Interface
Farnell TTL-232R-5v-WE
# 1 Ground (Black)
# 2 CTS# (Brown)
# 3 VCC (v5) (Red)
# 4 Interface TXD* Orange
# 5 Interface RXD* Yellow
# 6 RTS# Green

*Remember to cross connect the datalines (TXD<>RXD)