Replacing The Diaphragm And Gear Oil For Dosing Head With Single Diaphragm (No Diaphragm Leakage Detection); Drain Gear Oil; Removing The Dosing Head; Replacing A Single Diaphragm (No Diaphragm Leakage Detection) - Grundfos DMH 28X Instrucciones De Instalación Y Operación

10.6 Replacing the diaphragm and gear oil for dosing
head with single diaphragm (no diaphragm
leakage detection)
Warning
Wear protective clothing (gloves and goggles) when
working on the dosing head, connections or lines!
The dosing diaphragm should be replaced with each
gear oil change.
Before removing the dosing head, valves and lines,
empty any remaining medium in the dosing head into
a drip tray by carefully unscrewing the suction valve.
Only use original Grundfos gear oil!
Note
For product numbers, see "Service kit catalogue" on
www.grundfos.com
Pump model Version
DMH 280 Single/double
DMH 281 Single/double
DMH 283 Single
DMH 283 Double
DMH 285 Single
DMH 285 Double
DMH 286 Single
DMH 286 Double
DMH 287 Single
DMH 287 Double
DMH 288 Single
DMH 288 Double
Collect the gear oil in a container and dispose of it
Note
correctly.

10.6.1 Drain gear oil

Fig. 38 Drain gear oil
Pos. Components
B Locking screw
1b Gasket
F Oil-filling screw with dipstick
L Stroke-length adjustment knob
1. Unscrew the locking screw (B) and collect the gear oil in a
container.
2. Screw the locking screw (B) and the new gasket (1b) back in
and tighten securely.
Risk of leaking oil and damage caused by oil loss!
Caution
For each oil change, a new flat gasket (1b) must be
fitted!
Description
1.3 l DHG 68
1.3 l DHG 68
3.5 l DHG 68
4.5 l DHG 68
5.5 l DHG 68
7.5 l DHG 68
5.5 l DHG 68
7.5 l DHG 68
5.5 l DHG 68
7.5 l DHG 68
3.5 l DHG 68
4.5 l DHG 68
F
L
1b
B

10.6.2 Removing the dosing head

1. Close the suction and discharge lines and loosen the suction
and discharge valve connections.
2. Loosen the six dosing head screws (1q with 2q).
3. Remove the dosing head (2).
10.6.3 Replacing a single diaphragm (no diaphragm leakage
detection)
• Remove the diaphragm and fit a new diaphragm (Q) on the
suction side. See fig. 39.
2q
1q
2
Fig. 39 Replacing a single diaphragm
Pos. Components
1q Dosing head screw
2q Intermediate disk
2 Dosing head
Q Diaphragm
10.6.4 Fitting the dosing head
• Fit the dosing head and cross-tighten the dosing head screws
(1q with 2q) using a torque wrench.
See section 8. Start-up/shutdown
Note
start-up!
10.6.5 Filling with gear oil
Risk of leaking oil and damage caused by oil loss!
Caution
For each oil change, a new flat gasket (1b) must be
fitted!
1. Check that the locking screw (B) is tightened.
2. Slacken and remove the oil-filling screw (F).
3. Set the stroke-length adjustment knob (L) to "0".
4. Slowly add the hydraulic oil through the oil-filling opening (F)
until the oil reaches the mark on the oil dipstick.
5. Wait 30 minutes.
6. Let the pump run for approx. 5 minutes with a stroke-length
setting of 0 %.
7. Let the pump run for approx. 10 minutes with a stroke-length
setting of 40 %.
Q
for subsequent
31