Mira [B] fault codewhat it means and how to fix it

This code only exists on the Advance Flex and Flex Extra, the drain-pump-compatible variants, and understanding the architecture explains both the fault and the remedy. The pump is not there to boost the water supply. Mira’s guide forbids fitting the Advance to a gravity system at all; it is a mains-fed shower, and the pump it talks to is an Instantmatch by Whale drain pump, fitted in level-access wet rooms where the shower area cannot drain by gravity and the waste water has to be pumped away. The shower tells the pump when it is running. The pump is a separate assembly with its own transformer, and the shower and that transformer communicate either through a signal cable or, on the Bluetooth installations, wirelessly rather than through a cable. That means there is a radio link in the middle of the appliance, and radio links have failure modes that plumbing does not.

Code B is the shower reporting that it cannot reach the transformer. Mira publish three things to check and they map onto the three ordinary reasons: the transformer has no power, in which case its own power light will not be flashing green; the two units are out of range of each other; or the link has simply dropped and needs re-establishing. Their instruction is specific about the green light, which is useful — it gives an owner a way to tell "the pump is dead" from "the pump is fine but unreachable" without any tools.

The remedy Mira offer for the range case is worth flagging because it is unusual candour in a fault table. If the transformer is out of range, they say a hardwired connection may need to be installed. That is the manufacturer acknowledging that the wireless design does not work in every property and that the fix is to stop using it, which is a more honest answer than telling people to move furniture.

1. 1

   Find the pump transformer — mounted near the drain pump, which sits below or beside the shower area on a level-access installation — and confirm its supply is switched on at whatever feeds it.

   Do not open the transformer or the pump. This step is confirming a switch and looking at a light, nothing more.
2. 2

   Check the transformer’s power light is flashing green, which is the state Mira specify. No light means the fault is the transformer’s supply rather than the radio link.

3. 3

   If the light is green, work through the Bluetooth setup in the Mira guide to re-establish the link between the shower and the transformer.

4. 4

   Consider what is between the two units. Distance, a solid floor or a foil-backed wall are all enough to break a link that used to work.

5. 5

   If the link will not hold, ask about a hardwired connection. Mira name it in their own remedy as the answer when the transformer is out of range.