RBI Gas boilers - Page 19

Finned copper tube gas boilers & water heaters – Boiler Manual
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Figure 13 Multiple Water Heating Piping (CW Models Only) (See Notes)
NOTES:
1. When using intermittent pump and pump delay, locate HeatNet sensor with well in lower 1/3 of tank.
Install sensor with heat sensing compound.
2. Thermal expansion tank may be required, check local codes.
3. CAUTION: TEST WATER HARDNESS AND pH AT JOB SITE.
Be sure to specify when ordering the pH and water hardness. This must be measured before selecting heat
exchanger and pump. Consult the Heat Exchanger Graph before making selection.
4. Common piping must be sized for maximum combined heater  ow.
5. Hot water tanks should be equipped with a combination temperature & pressure relief valve.
6. MA Code requires an 1/8 in hole in check valve to compensate for thermal expansion.
7. Boiler and pump purging required. Air must be purged from 3-way valve after boiler is  lled. Use purge
valves provided. Purge valve may be located on pump  ange. On multiple boiler installations the  ow switch
may fail due to trapped air. See manual procedure.
Notice: These drawings show suggested piping con guration and valving. Check with local codes and ordinances for
speci c requirements.
Air Vent
Aquastat Union
Automatic
Thermometer
Flow Switch
Pressure
Relief Valve
Reducing Valve
Check Valve
Pressure
Pump
Valve
Balance Valve
Vacuum
Relief Valve
Temperature &
Pressure
Relief Valve
Drain Valve
(Typ.)
3-Way
Mixing Valve
1
D-18 REV.B
2
2
1
5
5
4
4
6
7
7
7
7