GAH Electrastream User And Installation Instructions Manual page 26

3
2 4
40
60
20
1 5
80
0
6
0
bar psi
Note
One Tundish is supplied with the
Electrastream, this should be fitted to the
hot water TPR discharge, see 4-5.
HIGHEST POINT OF SYSTEM
EXPANSION VESSEL
Fig. 4-4b Static Head
Note
Normally expansion requirement is 4% of
the system water content including the
unvented cylinder coil.
4-4.1 Notes on Heating System
1. The total output from the Electrastream for hot water and heating is 30,000 Btu
(9kW). The radiators should be sized to suit.
2. The schematic system shows a kick space fan assisted heater, these are efficient
space saving units, ideal for small dwellings.
4-4.2 Pressure Gauge
The pressure gauge is provided to indicate the heating system pressure.
When the system is full with cold water and all radiators are full, on and vented, the
gauge will show the cold fill pressure.
Set the red pointer to the cold fill pressure. If the system pressure, indicated by the black
pointer, falls below the cold fill pressure, it means that the system requires topping up.
4-4.3 Pump
Electrastream is supplied with a standard 3 speed central heating circulating pump and
isolating valves. This should be fitted in the flow from the indirect cylinder before the
bypass valve.
Normally the pump will be set at speed 2.
The pump is wired so that it is ON when the heating control system is set for heating ON
and the room stat is set higher than the ambient temperature - see wiring diagram fig. 3-3a.
4-4.4 Heating TPR Valve
The temperature pressure relief valve is provided to vent excess pressure from the
system. The valve will open when the pressure exceeds 3 Bar ± 10%.
The TPR valve can be manually opened by turning the red knob clockwise, to close the
valve continue turning clockwise until it clicks.
4-4.5 Heating TPR Valve Discharge Pipe
The outlet from the heating TPR valve must be piped using 15mm copper pipe to a
visible position outside the dwelling. The pipe must have a continuous fall and ideally
be terminated over a drain.
Local by-laws may require a Tundish to be fitted - see note.
The heating TPR valve may be plumbed to the hot water system discharge prior to the
Tundish, see 4-5.
IMPORTANT Scalding water and steam can be emitted from the
discharge pipe. Position the discharge so there is no hazard to property
or people (especially children).
4-4.6 Expansion Vessel
Maximum charge pressure
Pre-charge pressure
Capacity
An expansion vessel and mounting kit is supplied, this is suitable for systems with a
static head of up to 5 metres. If the static head is greater than 5 metres the charge
pressure of the expansion vessel will need to be increased. Increase the pressure using a
standard car tyre pump and pressure gauge when the system is empty (zero pressure).
Expansion vessels are suitable for systems requiring a maximum expansion of 7 litres as
detailed above. For systems requiring more expansion a second expansion vessel will be
required. BS7074 Part 1 includes information on this requirement.
INST INSTALLA INST INST INST ALLATION ALLA ALLA ALLA
1.5 Bar Maximum working temperature
1 Bar Maximum working pressure
8 litres for maximum system expansion of 7 litres.
TION TION TION TION 4 4 4 4 4
4 4 4 4 4
90°C
3 Bar
25