Suitable Plumbing - Combination Boiler
Digital Mixing Valve (High Pressure/Combination Boiler)
1. Combination boiler systems - the digital high pressure/combination shower can be installed with an instantaneous
combination boiler.
2. Unvented mains pressurized system - the digital high pressure/combination shower can be installed with an unvented,
stored hot water cylinder system.
3. Mains pressurized instantaneous hot water heater - the digital high pressure/combination shower can be installed with
systems of this type with balanced pressures.
CAUTION: High pressure mixing valves must never be plumbed to gravity systems. This includes mixed gravity
and mains pressure, for example, gravity hot and mains cold. Doing so will invalidate the warranty and potentially
cause product and property damage.
Use of Warm-up Feature with Combination Boilers
When using the warm-up feature (see Homeowners Guide) with the digital mixing valve supplied via an instantaneous
water heater/combination boiler, the user may experience a brief temperature fluctuation. This is caused by the normal
operation of a standard instantaneous water heater/combination boiler whereby the boiler will turn off when the flow is
stopped (as happens after the warm-up sequence has been completed). Upon restart of the shower, a cold shot will be
flushed through followed by a brief hot shot until the hot water supply has stabilized.
Showering Maximum Flow Rate
NOTE: The digital mixing valve can demand hot water quicker than some instantaneous water heaters/combination
boilers can provide, especially in winter when the mains water is colder. It is therefore possible that this mixing valve will
need to have its outlet flow rate altered to match the capability of the water system.
High flow rate demanded from low kW combination boilers will result in poor blend temperature stability and could
result in your shower going cold. We strongly recommend you to alter the outlet flow rate as the table below.
The flow rate can be adjusted using the Controller or using the App.
Boiler Rating
24 kW (80,000 Btu/h)
30 kW (100,000 Btu/h)
36 kW (120,000 Btu/h)
Outlet Flow Rate
2.2 gal/min (8 l/min)
2.6 gal/min (10 l/min)
3.2 gal/min (12 l/min)
Kohler Co.
5
1430528-W2-
A
