ORLANDO HVAC & INDOOR AIR QUALITY SERVICES Air conditioning companies in orlando florida

Carrier high efficiency units

Unlike some other brands carrier some what made it easier to diagnose using the old OBD1 vehicle diagnostics L.E.D Flashing systems.

In this article I will cover diagnostics characteristics ,parts location and also cover more curiosity that you technicians  many have some manufactures started building this high-efficiency units using one main board meaning inverter is combined with control systems also,so when one goes bad you must replace the whole board kinda like your uncles TV VCR combo or your mothers dryer washing machine together she refuses to get rid of.

Well carrier has two boards in their green systems meaning you can replace them one at a time they say the inverter is something you hardly would have to go into.


The 25VNO Heat pump condensing unit has a variable speed compressor,Infinity communication controls,variable speed drive,Highest efficiency,air source heat pump,HSPF,S UP TO 13,AND seer up to 20.5.

The benefits of it are:

Comfortable supply air temperatures,less dependency on auxiliary heating,performance approaches water source heat pump,at 17 degrees F’ THE VARIABLE SPEED HAS 86% More capacity 29% more efficient than the competitor I’m not here to promote this product lets move on.

Model numbers

Look below at the model numbers notice the change more like a car’s vin number every letter means something


Notice the board below has terminals such as ABC

to hook up thermostat wires for Both high and regular efficiency  on the right of the right side.


The Infinity series heat pump with Greenspeed intelligence is the first of its kind. No other ducted, air source heat pump can beat its 13 HSPFrating for heating efficiency. It’s a winner too, when it comes to cooling. But perhaps the biggest story is what it can do for your home comfort.

Greenspeed intelligence is created by pairing adaptable-speed technology with our Infinity control’s intelligence. The unique, variable-speed compressor of this unit, when managed by the Infinity control as part of a complete Infinity system, allows it to literally adapt its output to the needs of the home. With infinite adjustments between 40 and 100% capacity, it gives the home only the amount of cooling or heating necessary.



Notice the contactor below





Notice it has a muffler which is needed during high-efficiency mode


Line applications


Be careful



By now you get the picture this is new to all of us although you may have installed one or two it takes a few years for them to start breaking down so diagnostics knowledge know how is a must.


In any event you have to remove any wiring be sure to put them back exactly the way you’ve taken them out if they were looped loop them back the same way

L E D Flashing diagnostics so you would refer to your code chart

green systems by carrier

Living in florida what really concerns me is lightning:

by now you are probably thinking arrestors ,resitors of all types that can stop lightning from damaging these units! Yes that’sthe way technicians think ”A solution to the problem” But there are many ways the high voltage can travel to enter the unit maybe from a chain link fence. (National Electrical Code (NEC) requires you to install a second rod at least 6 ft away from the first rod, if the resistance of the first rod is greater than 25 ohms) or any other paths .My own solution is to use an earth ground away from the house ground as far as you can . you can use multiple rods personally I prefer copper because of its conductivity.





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