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Carrier Infinity Two Stage HP

I'll do the best I can to pass on what I know. Yes, its an Infinity Controller. Also, its an Infinity fan coil. The model on the fan coil is FE 4 ANB 006 and the condensor is a 38 YDB 036. A bud at Carrier said the HO is screwed because the condensor is what dictates the air flow as opposed to the Infinity furnace that uses a dip switch to match air flow to the condensor. As long as the condensor is set up for the 3 ton parameters, that's how the indoor unit is going to behave and the massive size of the indoor coil will wreak havoc on the rest of the components. Fortunately, I think my friend hired th right contractor and he just wants to see the system be right even if it does mean changing a fancoil.
Thanks for all the help.



  • Darin(in Michigan)
    Darin(in Michigan) Member Posts: 90
    Carrier Two Stage HP

    I'm helping a friend(yea, I know...). He just built a house on the East Coast. 1750 ft ranch. Carrier Infinty Two Stage Heat Pump (38YDB 036 310) and Fan Coil(FE4 AN 8006) He can't get the humidity in his house below 55%. The contractor usually puts in Rheem but my bud heard good things about the Carrier. My questions come in two parts.

    1) Is there a source for the troublshooting manuals for the heat pump and the fan coil or do I have to go through Carrier Direct?

    2) Is it possible that his expectations are too high and that the system no matter how well it is set up, the humidity will always be above fifty inside?
  • Constantin
    Constantin Member Posts: 3,782
    Did he perform a heat gain calc?

    ... i.e. does the system in there match what's needed?

    ... any sources of humidity in the house, such as wet slabs, moist walls, open crawlspaces, roof leaks, or other such nonsense?

    ... has the Carrier been hooked up with a 2-stage thermostat that knows how to control a 2-stage AC? While reviewing the installation manuals, do all the wires have continuity and do they go where they have to go? I ask because I have seen plenty of single-stage thermostats hooked up to multiple-stage AC/HP units.

    Does said thermostat perhaps have a humidity controller? That kind of a controller would run the fans at low speed while running the condenser at high speed to maximize the latent heat removal.

    ...I'd call Carrier and see what my options are re: thermostats and controls. However, even a two-stage system won't help you if it's much too big for the load - the two-stage scroll in my Lennox runs stage 1 at 66% of capacity... so it's not like you're ending up with very small loads.
  • John Mills_5
    John Mills_5 Member Posts: 935
    I'm with ya...

    Either it is WAY oversized, has tons of east & west glass or has no insulation to have 3 tons for 1750 sq ft new contruction. Around here, that could be done with 2 tons though more likely 2.5 ton.

    The YDB is 50/100% staging. Is he using the Infinity control? That has several methods of dehumidifying but if oversized, even the Infinity may not be enough to help.
  • Empire_2
    Empire_2 Member Posts: 2,343
    What's wrong with 50 to 55%RH???

    When operating in summer months, even on the east cost where it's very humid the A/C is doing well if maintaining a RH% below 60%. Is your HP air handler a variable speed? Like stated before if it's over sized, you have a problem. Temp/ pressure and heat gain to the structure would be nice to know due to the fact that your question has unlimited posibilities as to the possible problem. Just trying to get a-little direction from you my friend.

    Mike T.
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