CAPTAIN 10 (AV10PS) Greenhouse Ventilation Controller – Setup & User Guide

System overview

A greenhouse is like a living room for your plants. To keep them healthy you need to control temperature, humidity, air movement, and light. The CAPTAIN ventilation controller is the “brain” that does this work for you.

It connects to vents, fans, heaters, dehumidifiers, lights, and weather sensors. Using timers, setpoints, and safety rules, the controller decides when each piece of equipment should run, keeping the climate inside your greenhouse steady no matter what the weather is doing outside.

What the controller does

• Temperature control: vents open to let heat out, fans move air to cool crops and bring in fresh air, and heaters switch on to keep plants warm at night or on cold days.
• Humidity control: vents crack open briefly to release damp air, fans exhaust humidity and dry leaves faster, and dehumidifiers remove moisture when it is too cold or wet outside to vent.
• Light control: grow lights turn on and off on a set schedule, and light-deprivation curtains close to give crops an artificial “night” even during the day.
• Safety & weather protection: wind sensors close vents and stop fans when it is too windy, rain sensors close vents to protect crops, and master/slave sensor share lets one weather station protect multiple houses.

How it all fits together

• The controller has relay outputs (like light switches) to run vents, fans, heaters, lights, and dehumidifiers.
• It has inputs for temperature probes, humidity sensors, and weather sensors.
• You program parameters (P-numbers) to tell the controller what equipment is connected, what temperatures or humidity levels to react to, and when to run special features like DIFs or grow lights.
• Once set, the system works automatically, adjusting the climate minute by minute, protecting plants, and saving energy.

Why it matters for growers

• Healthier plants: stable conditions reduce stress, disease, and uneven growth.
• Higher yields: the right temperature, humidity, and light mean stronger plants and better harvests.
• Energy savings: the controller only runs equipment when it is needed.
• Peace of mind: safety rules protect crops during storms, cold snaps, and hot days.

A quick example day

• Morning: heaters switch on early, vents crack briefly to dry leaves, fans mix the air.
• Midday: vents and fans run together to cool, grow lights turn off.
• Evening: heaters stage on to hold warmth, fans slow down.
• Night: dehumidifier functions remove moisture, heaters keep the crop safe.

Main features

• Temperature DIFs with manual overrides
• Wind speed sensor option
• Humidity option
• Battery-backed clock
• 8 or 10 relay outputs
• Adjustable temperature settings
• Touch screen display
• Manual overrides

Installing the CAPTAIN

• Protect the enclosure from moisture. Mount it in a secure, dry place.
• Only drill holes in the bottom of the enclosure.

Wiring the temperature sensor

Place the temperature sensor in the middle of the building, or in a location that represents the building’s average temperature. Do not let sensors come into contact with direct sunlight.

Connect the temperature sensor to the Sensor #1 terminals. Polarity is not important.

Extending the temperature sensor

1. Run 18–22 AWG wire (twisted or shielded if possible) from the sensor to the CAPTAIN. Keep the sensor wire at least 1 foot away from high-voltage wire, and especially away from VFD output wires.
2. Solder or use gel-filled crimps to connect your wires to the temperature sensor.

Developer feature: 3 temperature probes

Up to 3 probes can be connected. You will need to move the #1 jumper to the T position.

Connecting the wind meter

A wind meter closes vents in high wind. Wind data can be shared wirelessly between units.

Mounting the wind meter

• Put the sensor outside where it can catch wind from all directions.
• Mount it upright with the rotating cups on top.

What if nothing shows up?

If you do not see any wind speed, adjust the config settings: set P29 = 1.

If the wind meter is spinning but the screen still reads zero MPH for a whole minute, something is wired wrong.

Connecting a rain sensor

You can connect a rain sensor to the system. The rain sensor closes select vent motors when it is raining. The system supports one rain sensor.

If you connect a rain sensor, the controller needs to know about it. Setup parameters P40 and P41 assign the sensor to the vent motors.

Installing the rain sensor

When installing the wires, keep the rain sensor cord 6 inches away from high-voltage wires. The vent motor’s close signal is activated when the sensor is wetted; the position of the sensor relative to the sky dictates the response.

Troubleshooting the rain sensor

Quick test: wet your hand and vigorously rub the clear dome of the sensor. About 30 seconds of rubbing should trigger rain. You will hear a faint click and a dim green LED turns on when triggered.

Controller does not detect rain: run the quick test. If rain is detected at the sensor, check the sensor connections and wiring back to the controller. All connections must be dry and corrosion-free. Wet or corroded connections need to be replaced.

Rain sensitivity

Rain sensitivity is adjustable, but it requires opening the rain sensor. Remove the 4 screws holding the sensor together to reach the switches inside. Adjust the switches as noted below, and keep the gasket in place when reassembling.

Sensitivity settings (switches 1 & 2)

The sensor has 4 sensitivity settings. DIP switches 1 and 2 set the rain-detect threshold.

15-minute reopen delay: normally the vent reopens after rain stops. To keep it closed for a while after the rain, set DIP switch 3 on. Normally switch 3 is left off so vents reopen sooner.

Connecting a humidity sensor

The humidity sensor lets you monitor and control humidity. If humidity is too high, a vent can open or a fan can start. If you connect a humidity sensor, activate it by selecting humidity for setup parameter P10.

Location

Mount in a central location. Keep the sensor away from heaters, or you will get a low reading while the heater runs.

Installing the humidity sensor

Route humidity sensor wires 6 inches away from high-voltage wires.

Powering the CAPTAIN

• AC versions come with a power cord. Plug it into a 120v outlet. Requires 120V, 5 amp.
• DC versions are either 12 or 24 vdc. Check the voltage labeled on your unit.

Controller relay outputs

There are 10 relay outputs on the CAPTAIN 10. Each has normally-open (NO) and normally-closed (NC) contacts, rated for a maximum of 0.3 hp or 7.5 amps, whichever is less. Each relay also has a green mechanical test button used to manually activate the contacts.

Each button on the screen and each output terminal is associated with the corresponding relay.

Motor connector bus bars

The motor connector bars are for low-voltage motors only. By default they include bus bars for the first 8 relays (4 vents). If you want to repurpose any of outputs 8, 7, 6, 5, 4, 3, 2, or 1 for another application (remapping), the bus bars must be removed from the remapped outputs. Remove the bus bar entirely, snip it with pliers, and reinstall it on the correct outputs.

Bus bars can be shortened or removed to connect fans, heaters, or lights instead of vent motors. To shorten one, remove the connector completely, then snip it to length with pliers. With the bus bar removed, the outputs become dry contacts.

Motor & device wiring examples

4 heaters and 3 low-voltage motor connections

Example connection of three 24v vents and four heaters. The three 24v vent motors connect directly to the terminals in this example.

Connecting 5 low-voltage motors

Fan connections (paired shutters)

Many fans can be connected. Wire the fan’s signal wires to the controller as shown. Paired shutters mean the inlet shutters open along with the fan motor.

Fan connection with independent shutter

Independent shutters can open before the fan starts.

Connecting DC motors

If the controller has a PS suffix in the part number, it includes a 24v motor supply. PS models are prewired to run several DC vent motors. Connect motors directly to the board as shown (connector bars installed).

120v or 240v vent motor

This shows a high-voltage motor wired to a contactor box. To keep it simple, the example maps it to relays 5 and 6, but you can remap it to any other set of relays.

Vent motor circuit breakers

There are several vent motor breakers, each protecting one motor. If a motor’s amps go too high, the center tab trips out. Press the tab in to reset.

Can I connect two motors to the same circuit?

It depends. If both motors run without tripping a 5 amp breaker, it will likely work. You are responsible for getting both motors to run in the same direction. This also increases the risk that a tripped breaker affects a larger area.

How big a DC motor can the CAPTAIN 10 power supply run?

It depends mainly on how hard the motor starts and moves. A rule of thumb: if it rarely trips a 10 amp breaker, it will likely work. The life of the replaceable relays will be reduced if the motor starts hard. The supply handles high-amp starts and a maximum of 15 amps.

Screen overview & overrides

The screen shows you what is happening, including the temperature and the status of the relays. Press the temperature to open your settings. Press the bottom row of buttons for manual overrides.

Overrides

Overrides let you force an output. In Auto, it operates automatically. Selecting Off or Forced lets you bypass the control system. The app’s temperature is shown, and all contributing probes are highlighted. To exit, press the blank space on the sides.

Temperature DIFs

Your controller has a feature called Temperature DIFs. DIFs let you temporarily change the temperature setpoints during certain times of day. In the morning, DIFs can help dry out the greenhouse by warming and venting more. In the late day, DIFs can help hold in heat by adjusting when vents open or close. Think of DIFs as a way to bend your normal heating and cooling rules for a short time to help the crop.

How DIFs work

• The status screen shows when a DIF is active.
• If you pressed “Force On,” the screen shows the DIF running even outside its normal schedule.
• To change when DIFs happen, press the clock button. DIF override buttons let you manually override any clock setting.

In simple terms

• Normal mode: vents open when it is too hot.
• DIF1 (morning): vents open a little sooner to dry the greenhouse.
• DIF2 (evening): vents close a little later to keep in warmth.
• You set the times and temperatures, and the controller does the rest.

Parameter reference

Parameters are labeled P1, P2, and so on. They hold the temperature setpoints and values you can adjust. From the parameter screen you can scroll between parameters and edit each parameter ID.

Vent parameters

Normal operation: vents open when the greenhouse is warm and close as it cools. During DIF1 (morning) they may open earlier to push out damp air; during DIF2 they may adjust to trap warmth. If it gets too humid, a vent cracks open briefly to dry the air unless it is too cold. If it is windy or raining, vents close safely until conditions improve.

Wind settings

The wind helper closes the ridge or side vents when wind is strong, lowering the risk of damage. You set how strong the wind must be before vents close (the high-wind event). When wind exceeds your number the vents close; when it slows they open again. Keep the clear (reopen) MPH lower than the high-wind event MPH, or the vents may cycle constantly and wear out the system.

Fan settings

Fans turn on when the greenhouse warms above their setpoint and turn off once it cools below the gap. During DIF1 (morning) fans may start earlier to push out damp air; during DIF2 they may run differently to manage late-day heat. With a humidity sensor, certain fans switch on briefly to dry the greenhouse. If outside wind is too strong, fans can shut down until conditions are safe.

Variable-speed (VFD) fans

A VFD makes 3-phase fans go faster or slower, but it does not tell the fans when to start (that is a separate relay). Fans run slower when cooler and faster when hotter, ramping with temperature. At full heat they run at 100%. You can also set one fixed manual speed.

Heater parameters

Heaters keep the greenhouse warm. The controller turns heaters on or off based on your setpoint. With multiple heaters it stages them so they do not all switch on at once: heater 1 comes on first, then heater 2, 3, and so on as the greenhouse keeps cooling, shutting off in reverse order as it warms. This keeps heating smooth instead of swinging hot and cold.

Dehumidifier parameters

The dehumidifier runs only when the greenhouse is too humid. Once on, it keeps running until humidity falls below the start humidity minus the hysteresis buffer, which prevents rapid cycling and saves energy. It is most useful when it is too cold or wet outside to vent.

Light deprivation (Light DEP) parameters

The Light DEP logic closes shades and vents when DEP is activated; afterward the vents wait 2 minutes in the reopen sequence. Shades only move when the shade time has elapsed. If vents are set to respond to Light DEP, they close as well.

Grow light control (the “sun clock”)

Grow lights act like an artificial sun. Set when the lights turn on and off so plants get the right amount of daylight. At the on time the lights turn on automatically and stay on until the off time. If a 2nd cycle is programmed, the lights turn on again at the 2nd on time and off at the 2nd off time. If the second cycle is left at 0:00, the lights stay off after the first cycle.

DIF timers

Hardware setup & configuration

Before the climate programs can run, tell the controller what equipment is installed: define your equipment (vents, fans, heaters, lights, dehumidifier), assign relays so the controller knows which switch powers each device, enable your sensors, and link probes to devices so each output responds to the right temperature reading.

Sensor share (master/slave)

If you have more than one greenhouse, Sensor Share lets one “Master” controller send its wind and rain readings to other “Slave” controllers, so multiple houses share the same weather information instead of each needing its own sensors.

• Master: acts as the weather station and broadcasts wind and rain data once per second.
• Slave: has no weather sensors of its own; it listens to the Master and reacts the same way.

How to set it up

• Master: set P38 = 1. To send wind data, also enable the wind sensor with P29. Rain status is always sent.
• Slave: set P38 = 2. To receive wind data, enable the wind sensor with P29. Rain status is always received.

Radio connections

The controllers talk via radios once per second. The TX and RX lights blink accordingly.

Diagnostics: the PWR LED should be on all the time. RX lights when the radio hears something; TX lights when it talks. If a Slave never hears anything, check whether the Master’s TX light comes on once per second.

Channels: DIP switches 1–4 pick the radio channel like a walkie-talkie. All switches off is channel 0. Put unrelated systems on different channels so they do not mix; any combination works, for 16 channels total. Controllers that should work together must share the same switch combination.

Boost: the boost switch makes the signal stronger. Only use it if controllers are not talking well, since a stronger signal can interfere with other devices and shorten radio life. The radio normally works up to 1,000 feet with a clear line of sight. Metal walls or screens block the signal.

Slave connectivity indicator: a red “!!!” means it is a Slave and no messages were heard in the last 3 seconds; “TX” means it is the Master; “.:|” means it is receiving messages.

Sharing sensor data over wires (RS-485)

Instead of radio, controllers can share sensor data over wire, daisy-chained from one unit to the next using 4-conductor twisted-pair 18-gauge shielded cable. Set the controllers up exactly as if using a radio (P38, P29, channels).

• Ground one shield end only. Connecting both ends can cause sensor problems.
• Keep away from high voltage. If high voltage touches these wires, all connected controllers can be instantly ruined.
• Keep runs short. Long wires can attract lightning. Cable can run up to 4,000 feet in theory, but it is proven to about 1,000 feet depending on gauge and load.
• Use the right cable. Follow TIA/EIA-485 standards. Good makers include Carol, Alpha Wire, Tyco/Raychem, and Belden. For best results, search “RS-485 best wiring practices.”

Remapping outputs

Think of the controller like a phone with different apps for different jobs. Changing which apps an output uses is called remapping, similar to reassigning the buttons on a game controller. Remapping is an advanced job done only in the setup menu. For a walkthrough, search YouTube for AutoVent LLC Captain.

Putting it all together

1. Define what equipment you have (vents, fans, heaters, lights, dehumidifier).
2. Assign relays so the controller knows which switch powers each device.
3. Enable sensors (temperature, humidity, wind, rain) so the controller knows what conditions to react to.
4. Link probes to devices so each vent, fan, or heater responds to the right temperature reading.

Troubleshooting

Controller continually reboots

Does it show an error at startup? If you see an error code right as it turns on, it is most likely a software bug or a parameter out of range. Report the error code and controller version number to tech support.

Does the controller reboot randomly? First, confirm 120v is consistent on the L and N terminals of the RS-15-24 power supply. If not, check the incoming power circuit.

If power is good, disconnect all rain, humidity, and wind sensors:

• If it stops rebooting with only the temperature sensor connected, a sensor is likely overloading the supply. Check the sensor wires and sensors.
• If it still reboots, check whether the reboot coincides with another device turning on or off. If so, see how that device is interlinked and disconnect it.

If none of that resolves it, work through these in order of significance:

1. Turn the power-supply voltage adjustment so the supply outputs about 23v (rare, but above 24v can be an issue). Compare your meter against a known DC voltage elsewhere.
2. Change the power supply – a bad supply could cause it.
3. Pull all relays out and check them – a shorted relay could cause it.
4. Change the lid.

Specifications

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