Filling And Draining; Filling - A.O. Smith ST-300 User And Service Manual

3
Legend
1. pressure relief valve
(mandatory if mains water
pressure is too high)
3. T&P-valve
4. stop valve (recommended)
5. non-return valve
(mandatory)
6. circulation pump (optional)
9. drain valve
11. service stop valve
12. temperature gauge
(optional)
14. draw-off points
15. expansion valve
(mandatory)
16. expansion vessel
(mandatory)
A. cold water supply
B. hot water supply
C. circulation pipe

3.1 Filling

Installation, Service and User Manual
ST 300

Filling and draining

Installation Diagram
To fill the water heater, proceed as follows:
1. Open the stop valve (11) in the hot water pipe and, if present, the stop valves (4)
for the circulation pump (6).
2. Close the drain valve (9).
3. Open the nearest hot water draw-off point (14).
4. Open the stop valve (4) on the cold water side (A) so that cold water flows into
the water heater.
5. Completely fill the water heater. When a full water jet flows from the nearest
draw-off point, the water heater is full.
6. Bleed the entire installation of air, for example by opening all draw-off points.
7. The water heater is now under water supply pressure. There should now be no
water coming out of the inlet combination expansion valve or (if used) out of the
T&P valve (3). If there is, the cause might be:
- The water supply pressure is greater than the specified value (1.6 "General
specifications"). Rectify this by fitting a pressure reducing valve (1).
- The expansion valve in the protected cold supply set-up is defective or
incorrectly fitted.
IMD-1285 R0
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