BSS Audio BOSS 100, Installation & Maintenance Manual, Page: 13 / 48

Boss Direct / Indirect Installation Guide
13
Dead Legs
The length of hot water draw off to taps and other outlets should be kept to a minimum to reduce the
amount of cold water drawn off before the hot water arrives. The maximum recommended dead leg
lengths are shown in the table below. Where there is more than one size of pipe on a dead leg, the
equivalent length and size should be estimated. Where the dead leg length exceeds the recommended
maximum, secondary circulation should be installed. It should be controlled by a time switch and
incorporate a motorized valve that can prevent gravity circulation in the circuit.
Pipe Size (mm) Maximum Length (m)
10, 12 20
15, 22 12
28 8
35 and above 3
System Noise
Noise in pipework may occur as a result of expansion of pipework over joists or where the pipe has
been left touching other pipes or a part of the building structure. Care must be taken to ensure that
the pipework is correctly bracketed, is not in tension or compression, and does not carry the weight
of components such as a circulation pump.
Setting The Hot Water Temperature
The hot water temperature is set on the dual thermostat by the competent person during the installation.
The dual thermostat should be set to 60°C. If you are heating water in the cylinder for the first time,
or the time controls for the DHW zone have been off for a prolonged period of time, the cylinder may
take additional time to heat up.
Inappropriate adjustments can lead to the damages in the system. If any changes are
made to the cylinder, the controls, the water and power supply lines or the expansion
relief components there is a risk of steam escaping or rupture to the system.