View Full Version : Lennox chiller flow switch

19-04-2013, 05:06 PM
Hi everyone!
Need info about this differential flow switch. Impulse hoses were disconnected by others and now Im not sure if I connected them back correctly.

install monkey
19-04-2013, 07:49 PM
shoud be markings to indicate hi and low pressure, turn the pump off see if it stops the chiller

19-04-2013, 09:41 PM
Hi Narcom.
Time to repay for all the times you have helped with info.
I have come across these and they are sensitive to how they are adjusted.
The attached should help?

Attached are 2 pages but the middle and most informative one is to big, so follow the link.

or download from the sontay site.
Please note there are 2 adjusting screws. 1 to trim the switch action and the other is a factory setting (not adjustable).

I have seen these when chillers have their water circuits in series. Meaning that when there may be more than one chiller running with others off.
You want each chiller to be able to sense that it's own pump is running and therefor it needs a made contact.
A flow switch would always be made as long as 1 of the chillers and its pump were on.
These are capable of recognising the slight increase it the water flow/ pressure across the individual chiller.
All you need to do is prove when the relevant pump is off the switch drops out!


19-04-2013, 10:07 PM
Also check out this labelled as Hubba!

20-04-2013, 06:15 AM
Thank you very much! The chiller does not stop when I turn off the pump.
Now I can get it sorted.