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249 VAN Launch Kit 249 VAN Consumer Brochure Smart Thermostat Sell Sheet 249 VAN Launch Kit

Unlock the Full Potential

View Quick Start Guide

This installation was on a 4-story home, and the tech had not yet gone to the basement to troubleshoot the “infinity” water source heat pump, as he was told he by the homeowner. He was in the attic at the infinity furnace above the 4th floor. He was getting his dcv in the proper range on his A and B green plug on the air handler, 3 to 4 vdc. His indoor board ohm reading was in range, 28k to 32 k. The tech ohmed out the A and B thermostat wires on the water source heat pump from the upstairs. His ohm reading was not in range of a normal infinity board. His reading was around 64.4k. The tech then made the long walk to the basement where the “geothermal heat pump” was located. Bingo. 

Now get out there and organize some zone wiring!

Zone equipment would be identified as indoor unit- blue black/ outdoor unit-blue green:

Two wire bundles with colored insulated strands and blue tape ties on brown cable ends.
CRM dashboard showing customer list, summary cards, and a highlighted button on the right

I have cropped some screens, and modified the serial numbers to keep certain dealer and customer’s information private. Setting the customers up on the portal is an easy process and could reap many benefits. Carrier and Bryant are going to begin utilizing this portal more with new upcoming equipment.


Get out there and get connected to the portal!

Dark “Edit System” settings dialog with multiple checkboxes and a blue Save System button
Marketing dashboard showing two “Connected Portal” cards with blue and red app icons.
Outdoor Control Details page with sidebar menu and expandable sections, highlighted by purple arrows on the right

These units are more complex and have more variables to consider.


*to keep things simple, we typically round close decimal numbers*


Min. Piping Length per each indoor unit- This is the minimum allowed amount of lineset for each indoor unit


Standard Piping Length per each indoor unit- this is the amount of lineset that has been “reserved” for each indoor unit for refrigerant charge purposes.


Max. outdoor-indoor height difference- how far you can separate the indoor from the outdoor vertically. Two labels are shown- IU indoor unit above OU outdoor unit and vice versa.


Max. height different between indoor units- if the indoor units are on different levels, then they should not exceed this amount of vertical separation amongst themselves.


Max. Length per each indoor unit- no indoor unit should have a lineset longer than this number. Do not exceed this number for any indoor unit lineset.


Max. Piping Length with no additional refrigerant charge- add together all of the lineset lengths for all the indoor units. If your lengths are above this number, then additional charge is needed.


Total Maximum Piping Length per system– when adding together all the indoor pipe lengths, this is the total length that the unit can support. Pipe lengths greater than this are not approved nor recommended.


Additional refrigerant charge- if your total lineset length is over the “Max. Piping Length with no additional refrigerant charge” amount, this is how many ounces per foot should be added to the unit for proper operation.


Pipe sizes: these show the pipe sizes with an asterisk (*) and then the quantity of those ports.
For example: from the 36K– 1/2 *2+3/8*2
This means 2 at ½ and 2 at 3/8.


In the event that the correct line set size is ran and it is not the same size as the hookup of this unit, use the factory supplied adapters to make the connections.

*Wiring diagrams highlighted with colors chosen for high contrast- not for wire color designation*

Low voltage starts in the red box at the transformer, 24vac goes to the Indoor Fan Board (IFB), through a fuse and on to the thermostat. Depending on what the thermostat calls for, 24vac will be sent down a different wire(s) to turn on/off the multiple devices in the system. The other low voltage wire (C) has an unbroken path to EVERY component in the unit. I have highlighted the pathway in blue and circled each component in purple. This wire/path is something each device has in “common”—it is the common wire. In layman’s terms, the common wire is the return pathway for voltage to come back to the transformer since it left out on the 24vac side.


The Common wire/terminal is always the one thing that is relatable or in common with the surrounding wires/terminals. Relays, motors, control boards, and even transformers all have some type of common wire/terminal. Common for a relay isn’t the same as common on a motor, but within each given device they carry the same meaning. Now go back and reread the second paragraph above—it will have a deeper meaning now.


Challenge: Check out the high voltage side of the Transformer. It has a COM terminal…. it’s not low voltage common. What is it?


That’s all.

Floor plan with a blue note bubble in the top right corner.

If a Wi-fi Network security key is shown as in the picture below enter the key and press Next.


The Iron Controller will inform you if the wi-fi connection was successful. Click Done

Picture of Kevin Thigpen

Kevin Thigpen

Technical Services Manager North Alabama District

October 14, 2020

Fan Coil Setup Parameters

Mingledorff’s Technical Services Group would like to cover the setup of an HVAC Fan Coil on an Ion Controller. Follow the steps to check and make changes to the parameters for Fan Coil.


You may need to make adjustment to airflow CFM per ton in order to help with sweating ductwork or a problem with air noise.

HVAC Fan Coil

Thermostat touchscreen showing 80° with up/down arrows, Home button, and menu options in cool mode.

Step 1

From the main screen press menu.

Bryant thermostat touchscreen showing settings menu with icons and back/done buttons

Then, press the down arrow button.


Black touchscreen HVAC control panel with service, photo upload, heat source, wireless, weather, and sensor icons

Step 2

Select the service cap. Press and hold it for 10 seconds or until it changes to green.


Bravant thermostat install and service menu with equipment summary, setup, and check out options on screen

Step 3

Select setup from this screen.

Thermostat setup screen showing fan coil, AC/heat pump, and heat source lockouts options

Then, Select Fancoil


HVAC touchscreen menu showing fan coil setup options for airflow, altitude, dehumidification, and G terminal input

Step 4

Select airflow


HVAC control panel with comfort/normal settings, up/down arrows, and cancel/save buttons

Step 5

From this screen, you can select Comfort, EFF, OR Max for cooling and same for heating. The dehum airflow is set to normal but can be changed to high if you have duct sweating.


249 VAN Launch Kit 249 VAN Consumer Brochure Smart Thermostat Sell Sheet 249 VAN Launch Kit

Unlock the Full Potential

View Quick Start Guide

This installation was on a 4-story home, and the tech had not yet gone to the basement to troubleshoot the “infinity” water source heat pump, as he was told he by the homeowner. He was in the attic at the infinity furnace above the 4th floor. He was getting his dcv in the proper range on his A and B green plug on the air handler, 3 to 4 vdc. His indoor board ohm reading was in range, 28k to 32 k. The tech ohmed out the A and B thermostat wires on the water source heat pump from the upstairs. His ohm reading was not in range of a normal infinity board. His reading was around 64.4k. The tech then made the long walk to the basement where the “geothermal heat pump” was located. Bingo. 


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