Mira Excel Installation & User Manual page 13

Mains pressurised instantaneous hot water shower, heated from a thermal
store
Packages of this type, fitted with a tempering valve can be used.
A drop tight pressure reducing valve MUST be fitted if the supply pressures exceed
5 bar maintained.
An expansion vessel MUST be fitted (and regularly maintained) if any form of backflow
prevention device is fitted, e.g. non-return valve, PRV. This will ensure that excess
expansion or pulse pressures do not damage the product or the plumbing system.
The expansion vessel may already be fitted externally or internally within the thermal
store (check with thermal store manufacturer).
Pumped showers (inlet pumps)
The shower can be installed with an inlet pump (twin impeller). The pump MUST be
located on the floor next to the hot water cylinder. The hot water cylinder/vent pipes
must be arranged as shown to achieve air separation.
COLD HOT
13
90°
30 to 60°
Air Separation