users of the 550

[pacnw]

for those who have used them or those that know, TruTech/Testo techs;

in the instructions there is a section that you select the monitoring mode- cooling, heating or auto.

it seems like the auto mode switches the display of the pressure without having to switch the hoses when a heat pump changes from heat to cool.

anyone know for sure?

thanks

[mark beiser]

That's what it does, not sure how useful of a feature it is, except maybe on some carrier products.

Also handy for those people that sometimes, for whatever reason, hook the blue hose to the high side and the red hose to the low side by accident.
If it has never happened to you, you haven't been doing HVAC/R work very long!

[jim bergmann]

That feature is for heat pumps that actually reverse flow by a different means than we typically see in the US. Viessmann manufactures a line of heat pumps not sold here that use this technology. The Testo 550 is sold world wide and that was a feature that Testo decided to incorporate to benefit technicians using that technology. I am guessing that we will see it on this side of the pond eventually.

Jim