And the other way round? Can I do it?In the case of showers from the 127V models without electronic control and a pressurizer, if the heating element is replaced by another one of the same model – but in the 220V tension – the shower will work normally in a 220V installation, as its internal mechanisms are sized to receive electrical currents and dissipate heat properly.
However, you should take care with the marks shown in the shower, which will indicate that is a 127V model. This may cause confusion in future maintenance or for new house owners. Therefore, you should by a shower in the proper tension.
In the case of a 220V shower the resistor should never be replaced for a 127V version and it should never be installed in a 127V network, since it is not prepared for such condition and safety may be compromised.