MAC MAC155H, Instruction Manual

Page: 52 / 143

MAC155 Rev. 12 ©Copyright MAC Instruments 2005. All Rights Reserved.
Pg 36
WATER TANK
Before servicing the water tank with the MAC155 Probe in place,
turn off the power and remove the power cable from the unit to
eliminate any possible contact with hazardous voltage.
The MAC155 Probe calibration system uses water that is stored in the water
tank to generate reference gases of a known percent of water vapor by volume.
The water tank holds enough water to last for over a year under normal
operating conditions. Do not wait for the low water level detection circuit to trip.
Instead, a regular maintenance schedule should be set up. The tank should be
drained, flushed, and refilled at least once per year.
Read the “OPERATION” section in this manual for information about filling
the tank.
When it is time to re-fill the water tank, proceed as follows:
1. Remove all electrical power from the instrument, and then open the
cover.
2. Loosen the mounting clamp on the barrel of the MAC155 Probe just
enough to rotate the instrument clockwise approximately 15 degrees.
This will assure that water will not run into the instrument when filling
the tank.
3. Siphon water from the tank as previous described.
4. Flush the tank as previously described.
5. Turn the instrument until it is approximately level and re-fill the tank
with distilled water as previously described. Install the fill plug and
make sure it is tight. Wipe up any water that found its way into the
instrument during this process.