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Answers to some frequently asked questions about CTM marine air conditioners.
To determine the amount of BTUs your boat needs you have to take into account several factors.
To calculate the amount of BTUs by volume (The total volume of the space to be air conditioned) first you'll need to calculate the volume of that space with the following formula:
Length x Width x Height
Cabin Length = 10'
Cabin Width = 7'
Cabin Height = 6'
10 x 7 x 6 = 420 cu. ft.
Once you know the volume of the space to be air conditioned the general rule of thumb for pleasure boats is using the formula of 14 BTU x cubic foot + 1,000 BTU.
Using the volume of the previous example:
420 cu. ft. x 14 BTU = 5,880 + 1,000
Recommended BTUs = 6,880 BTU.
Note: This example is intended to be used as a guide. There are many other factors which can influence the recommended BTUs. Seasonal weather, climate zone (Tropical, sub-tropical, Transitional, and temperate), insulation, sunlight, window sizes, humidity, ocean currents, etc should also be considered.
First of all make sure you have power supplying the unit. A red light on the center of the board indicates you have power. However, you should also make sure you have enough voltage (check your unit's voltage requirements).
Second, make sure your control/display is connected properly. 8-pin cables can only be connected to one place on the board; However, 6-pin cables can be connected in (2) two different places. Make sure it's connected to the right terminal. Refer to User Manual to determine the right location.
Reset control/display: Sometimes, re-setting the display fix most issues. 1. Make sure the display is connected to the U-board. 2. Turn OFF the power supply switch of the unit and wait 2 minutes. 3. Turn back ON.
Control/Display Compatibility: Although CTM Marine units use a universal board compatible with most controls/displays, some older models may not have the firmware necessary to work with the new boards. This issues are more consistent with older SMXir (2002-2006) and some older Passport i/o controls/displays.
Connect the unit to a new, updated and compatible control/display.
Thermostat set too low: Raise the temperature.
Improper Flow: Remove obstructions from the return air stream. Clean air filter and grille. Check crushed or obstructed ducting.
Supply Air is Short-Cycling: Redirect supply air so that is not blowing into the return air stream. Check and seal any leaks in ducting.
Humidity Too High: Close hatches, doors, portholes, to minimize humidity inside the air conditioned cabin.
Fan Speed Set To Low: Check your display's user manual to change these parameters. Increase the Fan Speed until unit stops freezing.
Retro-fitting a self-contained unit should be very simple since the location of the unit and the ducting is already in place inside the vessel.
CTM marine air conditioners are compatible with most thermostats used by other competitors.
CTM marine air conditioner units operate with a universal board that will make a retrofit very easy.
For more information about the CTM universal board click here!
Retro-fitting a unit is very simple since you should have a location and ducting already set inside the vessel.
Check if your current system is compatible with CTM Marine units here!
If you are installing a unit for the first time on a vessel that didn't have a marine air conditioner installed, please refer to the Installation Manual and follow the instructions carefully. Units not properly installed can cause serious injury or death.
You may download an electronic copy of the user manual by clicking the following link:
You may also watch an installation tutorial video by clicking the following link:
No, all CTM marine air conditioners come pre-charged with R410A gas.
Units may present a gas leak for several reasons. If your unit seems to have a gas leak, contact your closest CTM marine air conditioner authorized service dealer.
To connect the water pump to the unit, simply connect both active and neutral wires to the u-board on the unit.
On the bottom of the u-board, you should notice the labels Pump L2 and Pump L1 Click here for reference. Pump L2 is your active wire, Pump L1 is your neutral wire.
You may also check our tutorial videos here.
If you are installing a new pump, make sure it follows the guidelines as shown in the installation manual.
Water pumps should be installed under the waterline, unless the pump has self-priming capabilities.
Maintaining your CTM marine air conditioner is very important to extend the lifespan of your air conditioner.
Regularly clean the unit's strainer to keep good water flow in the system.
Clean the air filter regularly to keep good air flow.
There could be a few reasons why your unit is not cooling properly:
1. Make sure the thermostat is not set on heat mode.
2. Seawater temperature may be too high; the seawater temperature will affect your unit's efficiency. In order for the a/c unit to cool your boat properly, the water temperature should not be greater than 90 ºF (32 ºC).
3. Losing refrigerant gas. You should check your unit for any leaks, and contact your closest service provider.
Several causes may prevent your unit to heat properly:
1. Your thermostat is set on cool mode.
2. The reverse valve may be stuck. Try to tap the valve with a rubber hammer while on heat mode.
3. The seawater temperature is too low; the seawater temperature will affect your unit's efficiency. In order for the a/c unit to heat your boat properly, the water temperature should not be lower than 40 ºF (4 ºC).
4. Losing refrigerant gas. You should check your unit for any leaks, and contact your closest service provider.