Is the future of Fault Detection & Diagnostics really here?

In case you missed it, York has introduced one of the biggest advancements in the packaged rooftop unit industry since…? Microprocessor controls? The digital thermostat? I’m honestly not sure what the best comparison would be, but this is a BIG deal!

Just imagine this: It’s 5:30 PM on a hot and humid Friday afternoon, your customer calls and is frantically telling you about a unit that is not running in a mission critical area. It’s 100 degrees outside, and this needs to be fixed quickly, or your customer might call someone else. It could be a compressor failure, or maybe it’s a bad board or contractor, or it could be just a dirty filter. Either way, if you can get a technician to go take a look at the unit, you have NO idea what the problem could be.

Now imagine that this unit has the new Fault Detection & Diagnostics (FDD) installed. The story is much different now. Your customer notices the unit is down, pulls out his smartphone and sees that the unit is locked out on low pressure, and is under charged. Now when your customer calls, you know with very good certainty that all you will need is a jug of refrigerant and maybe a leak detector. 

How about another example, since these are fun. Your customer notices that all of a sudden the space is extremely humid, but can’t figure out why. The unit is running, and the temperature in the space is good, but just very humid. Again, your customer pulls out his smartphone, and notices that the economizer is opening when it should not be. So for now, we can disable the economizer function until a service technician can further troubleshoot the problem. The humidity problem is now temporarily fixed and can be looked at later. How cool is that?

So without further ado, here are the details you’ve all been waiting for…

The meat and potatoes, with gravy of course:
Factory installed option on all 3-40 ton York packaged units (excluding the small sunline).
Includes refrigerant pressure AND temperature sensors on EACH liquid and suction line. 
Provides a digital display and data logs of superheat and subcooling on your smartphone or tablet (and much more).
Refrigerant circuit alerts include (35 alerts possible):
Low/high refrigerant charge
Poor evaporator or condenser heat transfer
Refrigerant flow restriction
Low compressor pump efficiency
Non-condensable gas in system
Efficiency index & capacity index (ratios of ideal compared to actual operation)
Economizer alerts:
Failed economizer sensor
Economizing at wrong times
Not economizing at right times
Damper stuck
Excess outside air

Do you have customers that ask for reliable unit operation and can’t afford to have lengthy downtimes? Do you spend a lot of time troubleshooting unit or part failures? If you can think of one reason why this will or will not work for you or your customers, I’d would love to hear from you. Send me an email at or tweet us @cfmCommSales so we can talk about it!

Brad Telker
Connect on:
Latest posts by Brad Telker (see all)
This entry was posted in Rooftop Units and tagged , , , on by .
Back to blog