Checking And Changing The Motor Liquid; Checking The Motor Liquid; Changing The Motor Liquid On Sl Pumps - Grundfos SE Instrucciones De Instalación Y Funcionamiento

8.1 Checking and changing the motor liquid

Clean the outside of the pump at regular intervals in
order to retain the heat conductivity.
Change the motor liquid every four years to prevent
oxidation.
Lack of motor liquid may cause overheating and
FM
damage of the mechanical seals.
Use cooling liquid SML3 for motor cooling. Liquids
with lower specific heat capacity than SML3 may
FM
cause overheating of the motor.

8.1.1 Checking the motor liquid

You can check the ingress level of pumped liquid into the motor
liquid. Use a refractometer (product no. 98676968) which will
show the refractive index in percent of ingress.
Liquid ingress refractive index in %:
0 %: -22 °F (-30 °C)
5 %: -17 °F (-27 °C)
10 %: -13 °F (-25 °C)
15 %: -10 °F (-23 °C)
20 %: -8 °F (-22 °C)
If the refractive index is higher than 20 %, change the motor
liquid.
We recommend that you do not exceed this level of refractive
index in order to ensure that the shaft seal and the bearings are
in the best possible condition for reliable operation. For further
information, see service instruction for SE, SL pumps.

8.1.2 Changing the motor liquid on SL pumps

The shaft seal housing has two plugs as shown in figures
14.
Plug A is for checking the level of motor liquid and filling motor
liquid into the shaft seal housing.
Plug B is for draining motor liquid from the shaft seal housing.
Fig. 13 Checking the liquid level, pump in vertical position
18
Fig. 14 Checking the liquid level, pump in horizontal position
There must be minimum 10 % air in the seal housing
due to thermal expansion of the motor liquid during
operation
You can check the motor-liquid level by removing plug A either in
vertical or horizontal position. See figs
Draining the motor liquid
Place a container under the pump to collect all the drained-off
motor liquid. Tip the motor to horizontal position so that plug B is
pointing downwards. See fig. 14. Due to possible pressure build-
up in the shaft seal housing, open plug A cautiously and then
remove plug B. Allow all the motor liquid to drain from the housing
into the container.
WARNING
Pressurized system
Death or serious personal injury
- When loosening plug A of the shaft seal housing,
note that pressure may have built up inside the
chamber. Do not remove the plug until the
pressure has been fully relieved.
13 and
Dispose of the motor liquid in accordance with local
regulations.
Filling motor liquid, pump in vertical position
While the pump is standing vertically, fill the shaft seal housing
with motor liquid through hole A until the motor liquid level
reaches hole B. See fig. 13. Replace the O-rings with new rings,
insert the plugs and tighten securely.
Filling motor liquid, pump in horizontal position
Place the pump horizontally with plug B mounted and pointing
downwards. Fill the shaft seal housing with motor liquid through
hole A until the motor liquid reaches the level indicated in fig. 14.
Replace the O-ring with a new ring, insert plug A and tighten
securely.
13 and 14.