Vaisala MMT330 - Manual (Page 145)

Chapter 7 _______________________________________________________________ Maintenance
VAISALA _______________________________________________________________________ 143
CHAPTER 7
MAINTENANCE
This chapter provides information that is needed in basic maintenance of
the product.
Periodic Maintenance
Cleaning
Clean the transmitter enclosure with a soft, lint-free cloth moistened with
mild detergent.
Clean the sensor before storing the MMT330 probe and before
calibration. For cleaning of the probe you need instrument air and
heptane (C
7
H
16
) liquid. Dry with instrument air to prevent oxidation of
the oil on the sensor. The oxidation of the oil on the sensor can cause
extended response times or drifting.
1. Blow the probe with instrument air (with filter attached) to remove
the remains of the oil.
2. Immerse the probe into heptane liquid and rinse out the oil (for 1
minute maximum).
3. Dry the probe with instrument air. In case you are going to
calibrate the probe, remove the filter and dry the sensor with
instrument air. Check that the sensor looks clean.
Changing the Probe Filter
1. Turn the filter counter-clockwise to loosen it.
2. Remove the filter from the probe. Be careful not to touch the sensor
with the filter. Without the filter in place, the sensor is easily
damaged – handle the probe carefully.
3. Install a new filter on the probe. When using the stainless steel
filter, take care to tighten it properly (recommended force 5 Nm).
New filters can be ordered from Vaisala, see section Spare Parts and
Accessories on page 164.