If you set this option to on, each time the pump stops, due to flow stopping the
T20 will prevent the pump from restarting for the set period of time. The delay
time can be set from zero to 99 hours 59 minutes in increments of 1 minute. De-
layed restarting is a form of anti-cycling and cyclic running, wherein the pump is
limited in its ability to cycle on and off by preventing it from restarting for a set time
period. Its uses include preventing rapid cycling if the system’s air cell becomes
water logged or if a fault develops in the system.
Delayed Restarting
If you choose to use the delayed restarting function and press (P) you will be
asked to enter the delay hours and minutes. You will then be asked if you
want automatic starting at the end of the delay period. If you choose yes to
this question the T20 will automatically start your pump at the end of the de-
lay period. If you choose no the T20 will only start the pump after the de-
lay if flow pushes the paddle of the remote flow switch into the on position.
You may choose to set the delayed restart to perhaps 12 hours. At the end of
the 12 hour period the pump will automatically start and if the tank level is low,
the pump will run continuously until the tank fills and the float valve in the tank
closes. If however, there has been no draw-off from the tank during the 12 hour
period, the automatic restart at the end of the delay will start the pump and run it
for whatever period you have set on the start timer (perhaps a few seconds). The
flow switch connected to the T20 will sense no flow because the float valve will
still be closed. The T20 will then shut down the pump and again wait for 12 hours
before attempting to start the pump. Using this technique prevents the pump from
hunting on and off when the tank is full because of slight leakage from the float
valve or pipework. It allows you to set the pump to only operate after a chosen
delay, and if there has been no usage of water, to test the system for demand by
momentarily starting, and only run the pump if there is a genuine call for water.
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Summary of Contents for T20
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