A/C blower no good

quote:

Originally posted by BillyK

Hi guys,

That's the problem. I can't get to the motor. Should I drill out the rivets or grind out a hole. I don't want a basket case, but at this point why not.

Thanks,

Billy K.






Why not? Because when you get around to calling in a pro, you don't want to have to pay for damage that you did trying to fix it yourself.
 
quote:

Originally posted by BillyK

The original problem happened on Friday. We left it alone until today. I checked the caps and all seemed well. I started the unit on low fan and it ran fine. As I turned up the speed it made noise and increased amps, but not overload. I slowed it down until the noise stopped and it is still running. I still think I have a motor problem.

Thanks all,

Billy K.






What kind of noise? I've see blowers with bad bearings or other issues causing rubbing. Or it could be the motor...
 
Here is a pic of the capacitors and relay.

0708131827_zps30865cc9.jpg
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The motor is making a metal on metal screech on high, that goes away as it gets turned down.

Thanks,

Billy K.
 
If the motor is making noise and it ain't suppose to make noise, then I think you found your issue.
Again, no expert but that sounds like it to me.
Looks like you need to pull apart that blower housing next.

Or is there anyway to get another blower and wire it in and see if that solves the issue, without ripping out the other one.
If it does, you know its blower, if not then you return the blower and look at the caps.
 
Sounds like blower motor bearings to me. It reminds me of older computer power supply fan motor bearings many years ago, lol. When they went bad they used to screech until the motor warmed up and then it stopped until, of course, the power supply failed.
 
When a start capacitor stop performing it's task usually a visual inspection shows nothing. Sometimes a dimple at the top but not always. They don't blow like DC filter capacitors these will at times blow apart unlike the start capacitor.
I don't like the fan noise. Does it sound like a metal to metal squeal? If so the bearings are probably on their way out.
Here is what I think happened over the weekend. You were probably running the unit non stop. At some point it may have iced up. Then the unit draws excessive current and appears to go into sleep mode. In reality if it's a reverse air unit it might have actually tried to go into reverse mode to clear the icing. That's when you can get a high current condition that tripped the AC breaker. Once you came back to the boat to try some of the suggestions listed here the unit was obviously de-iced. At that point you started it on low and it ran as it should. As you increased the fan speed it still worked but you eventually heard the "noise". I believe the unit would probably run on high other than the noise it emits.
Have I properly listed the series of events that led to the unit tripping the breaker?
If the unit iced up you may have dirty filters, low water flow, low refrigerent or the unit might have been asked to perform outside it's normal range of operations.
Bill
 
That black capacitor looks like a Start Cap, the silver one looks like a Run Cap, and the white boxlike piece could well be a Start Relay. I'm working on the A/C on our "Boat With Wheels" (Motorhome) right now. It has a Start Cap/Relay setup for the Compressor in addition to its Run Cap. The Blower (1/3-HP 120VAC) uses only a Run Cap.
I mention this because I wonder if the box you opened is for Blower or Compressor. The Run Cap for a Blower is likely to be around 5-mfd. Run Cap for Compressor around 40-mfd. A Start Cap will be much higher. The common ones are 108-mfd.
A "stuck" motor (compressor OR blower) will overheat and trip its thermal cutoff, but it'll usually stay within the capacity of the breaker that supplies it. Tripping the breaker usually requires a Shorted motor.
 
He has a remote compressor so these are the start and run capacitors for the compressor not the blower, housed in the junction box near the compressor in the ER
 
quote:

Originally posted by CurrentSea

If the motor is making noise and it ain't suppose to make noise, then I think you found your issue.
Again, no expert but that sounds like it to me.
Looks like you need to pull apart that blower housing next.

Or is there anyway to get another blower and wire it in and see if that solves the issue, without ripping out the other one.
If it does, you know its blower, if not then you return the blower and look at the caps.




Dave, the blower needs to be mounted exactly where the original is on the MarineAir unit. This would be directly at the Evap. If you run the unit long enough without the proper air flow the compressor will eventually draw excess current and the AC breaker will trip.
This brings me to another point Billy you said there is no duct work? I see this being a potential problem because the air can circulate inside the box like assembly in the salon. You won't get anywhere near the maximum cooling from the unit by it being installed this way. Another tip if you can get to it pull and clean the Evap filter, it slides in small rails on the Evap (the filter's very thin).
Bill
 
That whole thing went in as a Unit. It comes out the same way. Then you can work on it easily.
 
quote:

Originally posted by Thudpucker

That whole thing went in as a Unit. It comes out the same way. Then you can work on it easily.






Not really, with remote compressor you can't pull the air handler assembly (blower, evaporator) with disconnecting the gas lines and having to recharge the system... Not a DIY job
 
quote:

Originally posted by Billylll

This brings me to another point Billy you said there is no duct work? I see this being a potential problem because the air can circulate inside the box like assembly in the salon. You won't get anywhere near the maximum cooling from the unit by it being installed this way. Another tip if you can get to it pull and clean the Evap filter, it slides in small rails on the Evap (the filter's very thin).
Bill






The evaporator is right against the bulkhead... Air is being pulled from the return and blown directly thru the evap and in the cabin. No need for duct. Fairly common on boats with remote compressors and just air handlers.
 
quote:

Originally posted by PascalG

quote:

Originally posted by Billylll

This brings me to another point Billy you said there is no duct work? I see this being a potential problem because the air can circulate inside the box like assembly in the salon. You won't get anywhere near the maximum cooling from the unit by it being installed this way. Another tip if you can get to it pull and clean the Evap filter, it slides in small rails on the Evap (the filter's very thin).
Bill






The evaporator is right against the bulkhead... Air is being pulled from the return and blown directly thru the evap and in the cabin. No need for duct. Fairly common on boats with remote compressors and just air handlers.







I agree now that it's clear this is a split system.
Bill
 
quote:

Originally posted by PascalG

quote:

Originally posted by Thudpucker

That whole thing went in as a Unit. It comes out the same way. Then you can work on it easily.






Not really, with remote compressor you can't pull the air handler assembly (blower, evaporator) with disconnecting the gas lines and having to recharge the system... Not a DIY job








While it's not a DIY job, unless your an A/C tech or have A/C gauges and know how to use them :-), you don't have to lose the gas. You can have a tech. do a pump down and let the compressor pump all the refrigerant into the condenser coils and then trap it there. So you don't have to add much, if any, gas after you change out the evaporator. You should have him or her add an inline gas drier when installing the new air handler.

As to the question of replacing the blower assembly if that is what turns out to be the problem, yes it can be done. And may involve drilling out pop rivets. I've done it a number of times with units in place and it can be a real PITA or impossible if you don't have good access.

That is just one things that is nice about chilled water A/C. If you need to pull an air handler you just turn off and disconnect the water lines going to it and remove the unit so you can work on it. No worries about loosing costly gas.
 
"That is just one things that is nice about chilled water A/C. If you need to pull an air handler you just turn off and disconnect the water lines going to it and remove the unit so you can work on it. No worries about loosing costly gas."

Show off :)

I wish...

By the time you gets a tech n the boat to recover the gas, you may as well let him replace the blower :)
 
We used to have a good Marine Airr and Cruise Air tech on the board Beaucomfort I haven't seen him post in awhile.
Bill
 
Thanks all for the advice. Billy, Marie changed the filter earlier in the day. The material she used was not to be used as filter material, so yes it could have froze the unit. I agree the caps in the compressor unit are not for the blower. At some point when it cools off, I'm going to drill out the rivets and see where I get. I'll let you know how I make out.

Thanks guys, you're the best.

Billy K.
 
Any updates Billy? Many people don't know about the Evap filter they get really nasty and can cause icing because they reduce the air flow through the Evap.
Bill
 
Hey Billy,

The fan on high makes a metallic noise when we start it up. If as Pascal suggested we start on low fan and bring it up slowly after a few minutes , it has not been a problem. Until last night. Out of the blue the breaker tripped just before we went to bed. I reset the breaker, but only turned on the the aft A/C. I will check out what happened later. I'm trying to buy time, but I'm pretty sure about the blower motor being the problem.

Billy k.
 
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