Teledyne 4250, Installation And Operation Manual, Page: 143 / 204

4250 Flow Meter
Section 5 Maintenance and Service
5-3
well ventilated room.
DO NOT use a microwave oven to recharge the desiccant car-
tridge. Heating the metal cartridge case in a microwave oven
will damage the oven.
Leave the room while heating the desiccant.
Avoid heating the desiccant longer than necessary.
Use the recommended temperature. Avoid heating the desic-
cant at higher than recommended temperatures.
Do not heat the plastic desiccant tube. It will melt in the oven.
5.2.2 Regenerating the
Desiccant Canister
Look at the desiccant canister each time you open the case. The
canister has a window on its side that appears blue or yellow
when the desiccant is dry. As the desiccant absorbs moisture, the
window will turn pale pink or green. When the window is pink or
green, you need to regenerate the desiccant, or replace it with the
spare canister provided in the flow meter accessory package.
Remove the canister from the flow meter by pulling outward on
the spring clamp, releasing its hold on the canister.
Remove the canister and heat it in a vented oven in a well-venti-
lated room at 300°F (150°C) for about three hours, or until the
blue or yellow color returns. Do not use a microwave oven; the
metal case of the canister could cause arcing. After cooling, rein-
stall the canister in the flow meter. Make sure the window on the
side of the canister remains visible.
Figure 5-1 Location of the Desiccant Cartridge
MSDS (Material Safety Data Sheets) for these chemicals are pro-
vided at the back of this manual.