Installation instructions
39
Greentherm T9900 SE/i – 6 720 813 635 (2019/03)
Fig. 31
Recirculation application
[1]
Cold inlet supply
[2]
Check valve field supplied
[3]
Expansion tank field supplied
[4]
Shutoff valves field supplied
[5]
Cold water inlet
[6]
Gas supply
[7]
Shutoff gas valve
[8]
Hot water outlet
[9]
Pressure relief valve
[10] Grundfos cross-over valve (X2)
[11] SS flexible hoses
Tank loading
This recirculation option gives the option of using one of three
temperature sensors to control the recirculation option. The
scheduling option is not available for tank loading.
•
External NTC
- 7 736 504 583
– Only compatible with Bosch cable/sensor accessory
(7736504583). Sensor must be inserted into the tank
pocket and plug in at the tank connector in bottom of
the appliance.
•
Aquastat
- - 7 736 504 584
– Compatible with thermostat type solution (example
Aquastat). Thermostat/Aquastat must be connected to
the appliance using the tank connector in bottom of the
appliance.
•
Internal NTC
– Allows tank loading without using any external sensor/
cable. Temperature readings will be made at the
appliance.
For more information how to program each menu, see
chapter 6.5.2, page 47.
4.11.3 Recirculation internal pump
Fig. 32
Hydraulic curve
Pump performance curve, shown in Fig. 32, is an extra
information for technical installer.
4.12 Space heating applications
CAUTION:
▶ If the set point temperature is above 120°F (49 °C),
precautions should be taken to protect users of potable
water from scalding.
0
1
2
3
8
7
6
5
4
0
2
4
6
8
10
12
H [ft]
Q [GPM]
672081363
5
-27
.
1V
