[skipshein]

We installed a new Carrier Infinity 19 Seer condenser. The control is a Honeywell IAQ. (Furnace is Heil 96% variable spd). The problem is that the condenser will not start/run in low speed. The IAQ is sending 24vac to Y1 on initial call for cooling but condenser does not start (furnace blower engages). Unit runs perfect with power to y1 & y2. If I then pull power from Y2, unit drops to low speed, amps drop about 25%(per Carrier claims) but units shuts down after ~20 sec. No error code noted from LED on Infinity board. Thanks in Advance, Skip Shein

 

[RyanHughes]

I assume this is the Infinity 19 heat pump? According to Carrier's product literature on the 25HNA9, "Infinity Control (MUST be used, no substitutes)."

 

[skipshein]

Unit is NOT a heat pump. Just 2 spd scroll condenser.

 

[BaldLoonie]

According to the installation instructions, the 19 can only use a standard stat in "emergency mode". I guess that means if your Infinity control dies, you can get some cooling.

Indoor Thermostat Control Options
Model Infinity Control Standard 2 ---stage Thermostat
24ANA7 Yes Yes
24ANA1 Yes No (Emergency Mode Only)

 

[skipshein]

Are you saying that even though the Honeywell IAQ has two cooling stages, the Infinity condenser will not function in low unless I purchase a matching Infinity thermostat & control?

 

[skipshein]

After reviewing installation instructions, I agree that Infinity controller is required. My furnace is Heil VS 2-stage. Will the Infinity controller operate this furnace. Does it also have 24Vac output relays? If not, is there an interface board?

 

[1-Hvacdoc]

The Infinity thermostat will not work with this furnace. It must be used with an Infinity furnace. There is not an interface. Your only option is to replace the furnace or switch to a different condensing unit.

 

[mark beiser]

OOPS!

On the other hand, you don't really need that silly control board to run a 2 step scroll in both stages, or even an ECM condenser fan motor in both speeds.

 

[skipshein]

Use of Y1/Y2 Possible?

Are you saying the interface Bd can be disabled thus providing control from Y1/y2? Why would they provide traditional G,C,Y1,Y2 connections if it is not possible to use these connections? Again, unit runs perfect on high(y2), Just no start on Y1.

 

[BaldLoonie]

So, Mark, is there any hope for him or does he need to swap out to the TS model of Infinity that will work with a non-Carrier furnace?

 

[mark beiser]

So, Mark, is there any hope for him or does he need to swap out to the TS model of Infinity that will work with a non-Carrier furnace?

Beats me, I don't know the Carrier products that well.

My comment in the previous post was more joking than anything.
The compressor and fan motor in the outdoor unit could be made to function as a 2 stage unit without the control board. It would likely have some warranty implications, but all that would be needed to "fix" the system is a rectifier and some reconfiguring of wiring.

The non communicating Trane XL16i straight cooling units use the same Copeland 2 step scroll compressor, and often an ECM fan motor, but don't have a control board at all, just a rectifier to rectify the 24vac from Y2 into DC to operate the solenoid in the compressor.
Y1 goes straight to the contactor, and Y2 goes straight to the rectifier to energize the solenoid in the compressor.

 

[BaldLoonie]

I'd say he's sunk on this one. Dealer who put it in needs to make it right, switch to the TS version of the Infinity which will work fine with the Heil and IAQ. OR better yet, put in a matched ICP system that could qualify for the tax credit.

 

[dougvhvac]

Ran into something similar on same product. Our situation was originally created by retrofit where existing control wire only had three wires available. It later became evident that this condenser needed to see 24v at the condenser C and R terminals, in addition to hitting Y1 or Y2. Several ways to resolve it, we intended to use add-a-wire but mounted dedicated trans in condenser.

Also learning that Infinity series products don't seem to love the new Honeywell stuff, but that can be worked out to some extent.

 

[skipshein]

So the refrigerant slide valve solenoid is 24Vdc and is normally de-energized or open in the low speed position? What controls the condenser fan speed? Just power on/off to different winding via a relay?

 

[skipshein]

Are you suggesting that 24vac be supplied constantly at R,C and then sending another signal to Y1 and Y1/y2 for Low/Hi control?

 

[dougvhvac]

Are you suggesting that 24vac be supplied constantly at R,C and then sending another signal to Y1 and Y1/y2 for Low/Hi control?

In essence, yes. We found that if R, C terminals were not powered, no go. Carrier local tech support helped us, suggest you engage them - each application has it's unique issues.

 

[jpsmith1cm]

forty305

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