For many years, PRIMUS has strongly and repeatedly advocated for the installation of a reverse osmosis system to provide pure water to PRIMUS integral and standalone boilers.

Poor quality feedwater is the root cause of easily avoidable sterilizer downtime issues, including fouling of steam valves, chamber discoloration, and check valve failures.

PRIMUS Sterilizer

While it is easier and more cost effective to purchase the R/O system (Option P-30) when ordering a PRIMUS sterilizer, installing an R/O system in the field is relatively simple and inexpensive.

A field installation should only take 2 – 3 hours if installed by a PRIMUS Authorized Service Agent (ASA) or an experienced in-house technician who has completed the PRIMUS InSpire Institute Sterilizer School.

The following information outlines the basic steps required to accomplish an aftermarket installation. PRIMUS service associates can help via phone or e-mail if unexpected issues arise.

NOTE: R/O water should be used for the boiler to increase the life of heating elements and the overall integrity of the boiler.

Preparing the Sterilizer for the New R/O System

1. Turn off all power and water to the sterilizer.

2. Follow all facility lockout/tag out requirements.

3. Disconnect city water to the boiler.

4. Remove the feed water pump and motor.

Installing the New R/O System

1. The R/O filter system is usually mounted on the back of the sterilizer, but can be mounted on the side if there is sufficient room. Some end-users also prefer mounting the system on an adjacent wall.

2. The water tank for the R/O system should be mounted just below the filter system. This tank holds approximately 10 gallons.

3. Place the new pump and motor in the same place as the pump that was removed.

The original pump and motor is a two piece design. The R/O System pump and motor is a one piece design.

4. Connect city water to the incoming port of the R/O system

5. Connect the R/O water from the filter to the top side port of the water tank. Connect the R/O waste water to the floor drain.

6. Connect the bottom port of the water tank to the boiler feed pump. Connect the feed pump to the boiler feed water solenoid.

7. Connect the tank overflow to the floor drain

The R/O tank has (2) floats.

The top float is mechanical and shuts off the flow of R/O water when the tank is full.

The bottom float is electronic and removes power to the boiler contacts if the tank runs low on R/O water.

The R/O low water float connects in series with the boiler low water cut off (LWCO) probe to prevent the pump from running dry for an extended period of time. (see the included boiler electrical drawing for the proper wiring configuration).

Returning the Sterilizer and Boiler to Service

NOTE: The R/O system for PRIMUS vertical door sterilizers produces approximately 100 gallons every 24 hours. The RO system operates best at 70 to 80 PSIG water pressure, but will work with water pressure as low as 40 PSIG. At 40 PSIG, the output is about half that at 70 PSIG.

1. Turn on the water to the R/O system.
2. Once the tank is full, turn On the sterilizer and the boiler.

NOTE: The boiler should be blown down to remove residual sludge from operating on untreated facility water. Boiler elements with hard scale should be thoroughly cleaned or replaced.

Have questions?

Email our resident PRIMUS sterilizer expert, Dave Schall , to answer your questions. Contact Dave at Spire Integrated Solutions at 877.679.7800 x1212.

Want to know more?

Water quality: why is it so important in a sterilizer?

Steam quality

PRIMUS water quality testing laboratory

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