The desiccator is a small part that can cause big problems in a 15 ppm bilge alarm. If it stops working, moisture builds up inside the measuring cell and the readings go wrong. This guide shows which desiccator fits your Deckma OMD, how to tell when it is spent, and how to swap it.
What the desiccator does
The desiccator keeps the air inside the measuring cell dry. According to Deckma, a worn-out desiccator can lead to condensation inside the measuring cell, wrong measurement and/or damage to optical components (OMD-24 EV manual, p.20). On the OMD-2005, the manual says the desiccator keeps humidity inside the measuring cell below 40%, to avoid wrong readings from condensation on the glass tube (OMD-2005 manual, p.18).
Which desiccator fits your OMD
Order by the RWO part number. The Deckma article number is shown so you can match it to your manual.
- OMD-24 / OMD-2008: RWO IEGUGU351636 (Deckma Art. 79550)
- OMD-2005: RWO CMSPGU316523 (Deckma Art. 65550)
Older RWO lists show IEGUGU327216 for the OMD-24 desiccator. IEGUGU351636 replaces it.
OMD-24 / OMD-2008
The desiccator comes in a sealed foil pouch. Keep it sealed until you are ready to fit it. The same desiccator is part of the OMD-24/2008 service kit. The cell cleaning brush for these models is RWO TOIESP313523 (Deckma Art. 77555).
OMD-2005 (being phased out)
The OMD-2005 uses a screw-in desiccator with a colour indicator: RWO CMSPGU316523 (Deckma Art. 65550). Its cell cleaning brush is RWO CMBRGU316522 / Deckma Art. 30102.
The OMD-2005 is being phased out. If you still run one, its desiccators and brush are worth keeping on board as common consumables for troubleshooting.
When to replace it
Deckma's manuals tie the desiccator check to the weekly measuring-cell cleaning.
- OMD-24 / OMD-2008: press the TEST button and read the desiccator status. If it shows anything other than "OK", replace the desiccator. You can also check the measuring-cell dew point: it should be lower than both the sample temperature and the clean-water temperature (OMD-24 EV manual, p.20).
- Servicing check: in the SYS menu, the measuring-cell humidity should be below 10 %rH and the dew point below 0 °C. If not, exchange the desiccator (Deckma OMD Series Servicing & Cleaning manual, §1.7).
- OMD-2005: blue means active. Light blue or white means replace (OMD-2005 manual, p.18).
The OMD-2005 manual recommends keeping 2 desiccators on board as spares (§15.1).
How to swap it
OMD-24 / OMD-2008 (OMD-24 EV manual, p.20)
- Unscrew the desiccator cap.
- Replace the desiccant container with a new one.
- Close the cap properly, then give the new desiccator some time to absorb the humidity inside the measuring cell.
OMD-2005 (OMD-2005 manual, p.18)
- Unscrew the old desiccator from the front panel. There's no need to open the instrument.
- Screw in the new one. The protection cap of the spare can be used as a tool.
After a swap, clean the measuring cell as usual. See our guide to cleaning the Deckma OMD-24 measuring cell.
Ordering
N&P Maritime is RWO GmbH's Singapore partner since 2016. We supply genuine Deckma OMD parts sourced through RWO, including desiccators, cell brushes and service kits. Send us your monitor type and the RWO part number and we will reply with a quotation within 1 business day. In-stock parts are delivered within 3 business days. Lead time is confirmed with each quotation.
Deckma OMD spare parts · Request a quotation
Sources
- Deckma Hamburg, Instruction Manual OMD-24 EV, Issue 28.05.2014, p.20 (weekly checks, desiccator Part No. 79550).
- Deckma Hamburg, Instruction Manual OMD-2005, Issue 27.05.08, p.18 (colour check, swap) and p.24 (spare parts, Art. 65550, on-board spares).
- Deckma Hamburg, OMD Series Servicing and Cleaning Manual, §1.7 Desiccator Check.
- RWO spare parts list (RWO part numbers IEGUGU351636, TOIESP313523; IEGUGU351636 replaces IEGUGU327216).