Can I use a Reactor without a hose thermocouple (FTS)?

Can I use a Reactor without an FTS? Discover the answer to this frequently asked question.

Is it possible to use a Graco Reactor without a fluid temperature sensor (FTS)?

This is a question we are often asked. The answer is: Yes, at least in some cases. In this article we explain when and how you can spray without a hose thermocouple.

Because the fluid temperature sensor (FTS) of the Graco Reactor is a sensitive device, it is often the first part of the system to break down in the event of misuse by the operator. It is the main reason why people ask us the question: “Can I use my reactor without the FTS?”.

Whether you can use a Graco Reactor without the fluid temperature sensor depends on your Reactor type and software version.

  • Do you have a Graco Reactor 2 with the latest software versionYes, then you can use a Reactor without the FTS (see further instructions below).
  • Do you have a Graco Reactor 1No, then you will need to use the FTS at all times.

How to use Graco Reactor 2 without an FTS

If you want to use your Graco Reactor 2 without the fluid temperature sensor, you must update your system to the latest software version (system version 4.01.002 or above). You can do this using the USB port on your Graco Reactor 2.

The latest software version allows you to activate Resistance Control Mode or Hose Resistance Mode on your Reactor to control the hose temperature without the FTS.

To prevent damage to the heated hose, a hose calibration is required in one of the following circumstances:

  • The hose has never been calibrated before.
  • A section of hose has been replaced.
  • A section of hose has been added.
  • A section of hose has been removed.

What is Resistance Control Mode (RCM)?

Resistance Control Mode (RCM) is Graco’s heated hose temperature control technology that automatically controls the average fluid temperature of the A and B material.

RCM uses the electrical resistance of the hose heating element to monitor the hose temperature. As the temperature changes, the electrical resistance will change with it. The Reactor monitors how the resistance of the hose changes in order to calculate the actual temperature.

Using the Resistance Control Mode to automatically control the hose temperature eliminates the risk of broken RTD cables and fluid temperature sensors, resulting in less downtime, less repair costs and increased productivity.

For more information, please read the Graco Reactor 2 manual  (333023, p. 50) and this article about Resistance Control Mode.


Refer to the manual for further directions:

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