Crusieair Fan Output

[JLR]

I am trying to get to the bottom of an issue on my 74. The output of the a/c fan in the VIP stateroom is pitiful. Frankly, it has been this way since I have owned the boat but I am finally getting around to trying to find out why. I have received feedback from Bruce Morrison and I would like to get some from the folks here to make sure I am not missing anything. Trying to break this down into bite sized pieces, I am trying to diagnose this problem as follows. First, make sure that the keypad adjustment for fan speed is per the manual. Second, as Bruce suggested, take the large hose off the blower and see what comes out before connecting the hose. Third, try to see if there is any blockage in the duct work. The output is not enough to blow out a match and, according to Bruce, this is not the way it was designed to work. If anyone here has any other ideas, I would appreciate some help. One last thing. The stateroom does cool off eventually but since I am moving so little air, it takes a while. Also, the fan is moving air but very little. Thanks.

 

[PeterK]

I will be following this thread. Air flow in my cabins is poor too. Pilot house is good. Just replaced the salon with an Ocean Breeze and it is phenomenal!
We have a big salon and it will cool from 84 to 72 in less than 15 minutes! To be fair, we did increase the air handler from 30K to 36K and the compressor is 32 from 30.

 

[JLR]

I am guessing that the VIP is about 10 x 15 including the head. Bruce confirmed that it is not a known design flaw that the air flow is inadequate in this stateroom. I am sure it is something fairly simple, like perhaps the PO messed up the duct work or something like that. I will report back when I know more. I also forgot to mention that I have already replaced the keypad so that is not the issue.

 

[bobk]

Some thoughts almost too simple to mention, but as a math prof once advised when trying to solve a problem, 'if you don't know what to do, do something'. The solution will come.

Return air filters clean? There might be more than one. How about the evaporator fins, all clear?

Kink in the supply duct? Disconnect at the blower, how's the air flow?

Is your blower a squirrel cage? Are the vanes intact?

Any strange noises or vibrations?

Good luck and please let us know the solution.

Bobk

 

[JLR]

Some thoughts almost too simple to mention, but as a math prof once advised when trying to solve a problem, 'if you don't know what to do, do something'. The solution will come.

Return air filters clean? Yes. There might be more than one. How about the evaporator fins, all clear? Don't know.

Kink in the supply duct? Don't know. Disconnect at the blower, how's the air flow? Will have that checked.

Is your blower a squirrel cage? unlikely since it is so quiet but not sure. Are the vanes intact? N/A

Any strange noises or vibrations? None. Very smooth and quiet.

 

[SKYCHENEY]

I'm guessing you need a new fan motor.

 

[JLR]

That would be an easy solution if that is what it is. I'll report back when I know. Is there some component that regulates the voltage to the fan to make it go faster and slower?

 

[SeaWhisper]

Do you have the SMX II electronic control panel. If so you can adjust the fan speed setting from 60 to 100%. PO may have drop the fan speed at full speed because he did not like the noise. Sometimes to slow will cause the air handlers to freeze up. Just a thought.

 

[northshoreone]

How old is the unit? Evaporator fins could be plugged with mildew or mold! I had to replace two of my units in the master dew to that condition, left unchecked by a previous owner. I get good airflow in the forward stateroom of my 70 witch is the same as yours I believe. I'm betting the fins are plugged thus killing airflow if its an older unit.

 

[JLR]

Do you have the SMX II electronic control panel. If so you can adjust the fan speed setting from 60 to 100%. PO may have drop the fan speed at full speed because he did not like the noise. Sometimes to slow will cause the air handlers to freeze up. Just a thought.

Thanks. Tried that adjustment to no avail.

 

[JLR]

How old is the unit? Evaporator fins could be plugged with mildew or mold! I had to replace two of my units in the master dew to that condition, left unchecked by a previous owner. I get good airflow in the forward stateroom of my 70 witch is the same as yours I believe. I'm betting the fins are plugged thus killing airflow if its an older unit.

As far as I know, the unit is OEM 1996. Also, I am not referring to the forward stateroom but rather the guest stateroom closest to the ER.

 

[northshoreone]

Mine are/were 1996 as well and the master units were plugged almost solid when I bought the boat. The mid stateroom unit also supplies the air to the head in that room so its volume is less than the forward stateroom unit. I am close to replacing that unit as well as I believe it to have a very slow leak of gas and it also has corrosion just not as bad as the master units were. Its on my list for the near future. I would take off the exiting end hose and get a good look at the fins. The salt air over the years eats them up!

 

[JLR]

Thanks for the head's up. I'll have the fins checked as well.

 

[JLR]

Initial efforts to reset the fan speed have failed. Further work will ensue soon. However, before I assume that the fan is the problem, I would like to confirm, once again, that there is no modular electrical component that may be to blame. Since I do not profess to know what they do, could this be a trigger or triac issue and not a fan or duct work issue?

 

[Reefgeorge]

So you have the SMXII control panel?

George

 

[JLR]

Correct.

 

[saltshaker]

How do you set the fan speed max on the SMXII? I have marginalnair flow in one of my staterooms and everything else is fine

 

[Boatsb]

The fan controls are at the bottom.

It can be set to any setting or to automatic where it speeds up when needed to cool and goes to slow when reaching temp.

 

[davidwigler]

How do you set the fan speed max on the SMXII? I have marginalnair flow in one of my staterooms and everything else is fine

Low fan speed is: press Off, then Set, then Down and Set simultaneously.

High fan speed is: press Off, then Set, then Set and Slow simultaneously.

PM your email address to me if you'd like a copy of the manual.

 

[tonytrakovich]

Your AC unit is on the aft bulkhead of the VIP stateroom correct? If so, it is same as mine. If you look in the VIP closet, there should be an access panel to the AC unit. Much better access than going through the drawers. There may be 2 filters. One behind the air intake vent. And one on the evaporator coils themselves. Make sure both are clean. I have no flex duct between the intake vent and the evap. You should have a squirrel cage blower. You will not be able to see fan blades unless you remove the fan output duct. May be a good idea to remove the duct anyway to check output on blower. You should hear what sounds like full rpm on the blower. If you don't then you have a blower issue. Does the motor case get hot? On your SMX II controls, if you have full green leds on the fan speed indicator then you should have near 220 v on the fan motor. Just some random thoughts on how I would start troubleshooting. All stuff you can do yourself.