Flow Switches Made in the U.S.A.

Installing a PEECO Flow Switch

Installing a PEECO Flow Switch
Installing a PEECO Flow Switch

  1. Optimal installation will allow a straight run of pipe for 10 diameters upstream and 5 diameters downstream but the switch can be successfully installed in less than optimal conditions. The additional turbulence can be compensated for by careful selection of the return spring and/or perhaps a shorter paddle length.  Please let us know if these conditions exist at the quoting stage.
  2. Optimal installation is vertical (within 5°) on a horizontal pipe run. However, the switch can be mounted in any position rotational on the axis of the pipe*. If vertical piping – adjust for gravity with spring tension (B).  Please let us know at the quoting stage if you do not plan to install the switch vertically in a horizontal run of pipe (as depicted in the graphic to the right). * Keep in mind that mounting in a horizontal position on a vertical pipeline will effect the switch’s activation/deactivation capabilities.
  3. Tee models install directly in the pipe run. Do not alter paddle.
  4. Screwed models are to be installed with a weld-a-let, thread-a-let, or half coupling.
  5. Cut paddle length to within approximately 1/2” clearance from the bottom of the pipe. Contour corners as necessary to insure no contact with pipe. The flexible paddle should always be within the run of pipe. If a riser is present, the 3/8” round stem should run the length of the riser before the point of paddle attachment.
  6. Mount switch with conduit connection downstream (pointing in the direction of flow).

All PEECO switches require field setting unless calibration has been requested and provided.
Switch adjustment should be made in the middle of the physical range of movement.

Adjustment (field setting) procedure:

  • Disconnect current.
  • Remove switch cover.
  • Screw actuating rod (A) in or out to point at which micro switch clicks.
  • Increase or decrease tension on return spring as necessary to overcome spring balance.
  • All turns should be done carefully and in small steps.
  • Screw cover on tightly before re-connection of current.

Return springs (B) may be changed as needed for greater or lesser tension (higher or lower flows). Springs are color coded only as to varying weight or tension – not as to quantitative flow range.

The flow switch is fitted with a color coded spring. The lower the flow trip point, the softer the spring should be.

Installing a PEECO Flow Switch

There are seven springs available:
1. Brown (Softest)
2. Red
3. Orange
4. Yellow
5. Green
6. Blue
7. Purple (Stiffest)

In the absence of any flow data from the customer, PEECO fits the red spring as a standard. (If the switch has too soft a spring, there is a possibility that a high flow trip point cannot be achieved.  In addition, the switch can bounce on and off due to the turbulence created around the paddle at higher flow conditions).

To get a lower trip point, the red spring should be swapped out for the brown spring. Once this is done, the trip point screw should be adjusted so that the micro-switch just activates under a no-flow condition.

If the flow switch will still not activate with the low flow, a wider paddle (1-7/8″) can be provided to increase the force produced on the switch at the lower flowrate. If you change to the wider paddle, you may have to adjust the trip point screw to offset for the additional weight of the larger paddle. The downside of doing this is that more pressure drop and turbulence is created at higher flow rates, which may lead to the bouncing effect described above.

PEECO Spring Kit
PEECO Spring Kit

Relieve Pressure Prior to Disassembling Switch Components.

Switches Equipped with a Dashpot

Time delay of the pot can be adjusted by screwing in (shortening time) or out (lengthening time) the small orifice plug at rear of cylinder. Do not tamper with any other part of the dashpot.

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Recommended Spare Parts

PEECO Spare Parts