Rebuilding a Cruisair FX16C condenser

[Reefgeorge]

Both of my 2002 Cruisair FX16C (R22) condensers have seized compressors and need to be rebuilt. I already have the replacement compressors and need to decide what else to replace while I am at it. I am EPA certified and have all the equipment but this is my first marine compressor failure. A few questions:

1) Do either the accumulator or receiver have screens and/or desiccant such that their replacement is a good idea?

2) Do the reversing valves fail often or should I just leave those alone? That's a lot of extra cutting and brazing.

3) Are the heat exchange coils prone to leaking and should they be replaced. They were never acid washed and the tube ends look good but I assume that a coil failure would be a real disaster with salt water in the lines and evaporators.

4) Do you guys flush the linesets and if so, how.

5) Do you put a filter/drier in the liquid line and if so, where?

Thanks,

George

 

[SKYCHENEY]

When I replaced my condenser, it was a complete unit. I did not flush the lines or evaporator, just vac it down and fill. I've had no problems in 2+ years since replacement.

 

[Reefgeorge]

When I replaced my condenser, it was a complete unit. I did not flush the lines or evaporator, just vac it down and fill. I've had no problems in 2+ years since replacement.

Was that a brand new condensor or a rebuilt one? If rebuilt do you know what was replaced?

Thanks,

George

 

[Boatsb]

I usually replace the whole unit but sometimes a compressor. its not worth putting new parts on old worn out gear.

The reversing valve is a PITA but if its fried or has debris you have to change it.

The driers are easy to add I just add one to the liquid line when I open a system. If I sometimes add a sight glass too to keep an eye on things.

Why did 2 compressors lock up? Did they overheat? did they grenade parts in the refrigerant? Something to look into before replacing them.

 

[SKYCHENEY]

Was that a brand new condensor or a rebuilt one? If rebuilt do you know what was replaced?

Thanks,

George

New one

 

[Reefgeorge]

I usually replace the whole unit but sometimes a compressor. its not worth putting new parts on old worn out gear.

The reversing valve is a PITA but if its fried or has debris you have to change it.

The driers are easy to add I just add one to the liquid line when I open a system. If I sometimes add a sight glass too to keep an eye on things.

Why did 2 compressors lock up? Did they overheat? did they grenade parts in the refrigerant? Something to look into before replacing them.

The first unit for the cabins failed a while ago. I just left the cabin doors open and the main unit handled everything until it failed recently. I don't think that the failures are related. Neither unit showed evidence of a burn out when I reclaimed the R22 so I don't think that either one imploded.

Do you put the dryer in the line set after the service valve or in the piping for the condenser? My line sets turn right after the service valves and virtually disappear behind the units on the outboard side. Can the original receiver be replaced with a receiver/dryer?

What about the condenser coil? Do you change those as well or just leave the original coils in place? I don't know how often those fail and risk dumping salt water into the refrigerant circuit.

Thanks,

George

 

[Reefgeorge]

I am in the process of replacing the compressors in the existing condensing units.

1) What do you guys do about the oil charge in the new compressor given that some of the initial compressor charge is now distributed throughout the system? One of the old compressors had 25% of the factory charge in it when I poured it out and the other one has about 50%.

2) Where do you put the filter dryer? Because of the liquid line routing near the condenser, putting it there is a problem, especially given that it may need to be replaced after a start up period. I might be better off up at the evaporator in the brow as apposed to down near the condenser? Braze or flare?

3) Do you ever also use a temporary suction side filter (one of the compressors was a partial burnout with some acid and gunk)?

Thanks,

George

 

[Reefgeorge]

I decided to rebuild both condensing units and the failed salon blower. Got the OEM Tecumseh compressors from PTAC for $290. New American made high grade run and start capicitors. Had the suspect logic board rebuilt by flightsystems.com with a warranty for half of new. Found the exact blower motor in an unrelated blower assembly from Amazon (Fasco B45227-2) for around $100. Parker bidirectional filter dryer from Zoro Tools for $30. New water cooling pump from Tesco pumps. Stayed with R22. Of course this is only cost effective if you have brazing and refrigeration skills or have access to the work for good prices but if you do it beats $3k for a new condensing unit installed. Also, most of the components need to be in good shape. My heat exchangers had never been acid cleaned so they were in good, etc.

I was staring at a $6k+ bill and I did the whole thing for around $1k and everything works great.

 

[Milacron]

I decided to rebuild both condensing units and the failed salon blower. Got the OEM Tecumseh compressors from PTAC for $290. New American made high grade run and start capicitors. Had the suspect logic board rebuilt by flightsystems.com with a warranty for half of new. Found the exact blower motor in an unrelated blower assembly from Amazon (Fasco B45227-2) for around $100. Parker bidirectional filter dryer from Zoro Tools for $30. New water cooling pump from Tesco pumps. Stayed with R22. Of course this is only cost effective if you have brazing and refrigeration skills or have access to the work for good prices but if you do it beats $3k for a new condensing unit installed. Also, most of the components need to be in good shape. My heat exchangers had never been acid cleaned so they were in good, etc.

I was staring at a $6k+ bill and I did the whole thing for around $1k and everything works great.

Neat that you did that. I've got an early 90's vintage Cruisair FS7C (7K BTU) condenser unit that needs new compressor, R22 system. Do you think a replacement for a compressor that old would be available ? (who is PTAC ?)

 

[Reefgeorge]

ptacsolutions.com. An online source with good prices and good service for compressors.

Mine was easy to figure out because the original OEM label is on the old compressors and that exact model is still made so all I had to do was find a good price. Others have warned that "equivalents" may have problems in these units. Does yours still have a legible OEM sticker on top of it?

 

[Milacron]

ptacsolutions.com. An online source with good prices and good service for compressors.

Mine was easy to figure out because the original OEM label is on the old compressors and that exact model is still made so all I had to do was find a good price. Others have warned that "equivalents" may have problems in these units. Does yours still have a legible OEM sticker on top of it?

Thanks. The compressor does have a metal data tag on top still in place...not sure about the legible part...will check it today.

 

[Reefgeorge]

BTW, you should also test the oil for sludge and acid because if you had a burnout, additional clean up is in order which I had to do on one of the units.

 

[Milacron]

BTW, you should also test the oil for sludge and acid because if you had a burnout, additional clean up is in order which I had to do on one of the units.

The compressor still runs but for only 5 seconds before system shuts down. It starts ok but maybe 2 seconds but then slows down and system shuts off. Not R22 pressure related and not run/start capacitor nor is it main relay related (known because I have switched all 3 components from good unit to bad and vise versa with no changes in either unit)

So, it runs but motor is weak. Voltage is fine at motor when running, keep forgetting to bring clamp ammeter to check amps but if I temporarily straight wire the thermal overload, the compressor motor will keep running (allbeit too slow and strained) until the panel breaker trips, so from that one assumes the amp draw is "too much" whatever it is.

To know absolutely the compressor motor is shot, and not some other strange problem, any suggestions ? Megger to get reading on motor windings, perhaps ? Or maybe compressor motor is ok but under undue strain internally due to other component ? (sounds ok though...no broken bearing noise for instance)

 

[Reefgeorge]

Some things to consider:

Have a gauge set on the system so you can watch the pressures at shutdown, especially the high side.

Have a probe on the output of the compressor thermal switch to confirm that it disengages.

Monitor compressor amp draw as it goes through the cycle. Same for voltage.

Measure the compressor winding resistances

Do you have any control panel codes?

Was the triac replaced?

Are you sure that both units independently generate good water flow?

George

 

[Milacron]

Some things to consider:

Have a gauge set on the system so you can watch the pressures at shutdown, especially the high side. static discharge pressure is 150 psi and remains at that pressure during the brief compressor run.

Have a probe on the output of the compressor thermal switch to confirm that it disengages. It does disengage.

Monitor compressor amp draw as it goes through the cycle. Same for voltage. Voltage is constant, assume amp draw rises as it runs but haven't checked that yet

Measure the compressor winding resistances With ohmeter or megger ? What figures to expect with ohm meter ?

Do you have any control panel codes? No, in fact that SMX 1 panel shows the "cool" light on even when the compressor has stopped. In other words the control panel thinks everything is just fine even when it is the opposite of fine

Was the triac replaced? No. What does that triac do exactly ?

Are you sure that both units independently generate good water flow? Yes, good water flow on both units

 

[Reefgeorge]

Milacron
Re: Rebuilding a Cruisair FX16C condenser

Some things to consider:

Have a gauge set on the system so you can watch the pressures at shutdown, especially the high side. static discharge pressure is 150 psi and remains at that pressure during the brief compressor run.

The discharge pressure would normally climb to over 200 psi if the system has time to stabilize. 250ish.

Have a probe on the output of the compressor thermal switch to confirm that it disengages. It does disengage.

Monitor compressor amp draw as it goes through the cycle. Same for voltage. Voltage is constant, assume amp draw rises as it runs but haven't checked that yet.

The most telling reading would be if the amperage gets near the LRA (locked rotor amp) spec.

Measure the compressor winding resistances With ohmeter or megger ? What figures to expect with ohm meter ?

Regular ohm meter. I belive that most compressors should read single digit ohms, both legs to ground, both legs together. Once you have the compressor model you can look up these numbers as well as normal and LRA amps.

Do you have any control panel codes? No, in fact that SMX 1 panel shows the "cool" light on even when the compressor has stopped. In other words the control panel thinks everything is just fine even when it is the opposite of fine

Was the triac replaced? No. What does that triac do exactly ?

Some systems have a triac or relay to switch the high current for the compressor and/or the water pump. Like a residential AC contactor. If the voltage does not sag badly and you get to LRA at shutdown, this is probably not your problem

Are you sure that both units independently generate good water flow? Yes, good water flow on both units

 

[Reefgeorge]

Also, what is the suction pressure at shutdown?

 

[Finalee]

Ok so what was the amp draw and low side reading at shutdown?

 

[Milacron]

The most telling reading would be if the amperage gets near the LRA (locked rotor amp)

Aprox 14 amps when it shuts down. In constrast, the same but slightly larger unit (10,000 BTU) draws 5.2 amps while running.

 

[Milacron]

Have a guy doing repairs on our house that happens to be a liscensed AC guy and he was enthused to see my setup on the boat. He listens to the Cruisair 7K BTU condenser try and run and says the compressor is locked up. He has replaced many compressors before and wants to replace just the compressor, says it should be fine...if we can just figure out what the model is.

Can't read the original metal plate but I can tell from other units it is a Tecumseh. So I find the same physical size, same gas (R22) and voltage (230) unit on the Tecumseh website. Rated for 6,500 BTU rather than the 7,000 the condenser unit is rated for. Tecumseh tech says that is close enough, due to water cooling.

But then it turns out they only make that one for OEM's....in fact he says they shipped a hundred or so of them to Cruisair last year. The only one that physical size and gas available for general distribution is the AEA5460EXA....even Amazon has that one. The catch is, it is 6,000 BTU and 115 volts.

So this brings up two questions-

1. Would Cruisair sell me the AEA5465EXD or are those units probably for their repair folks only ?

2. Would 6,000 BTU be close enough for 7,000 BTU rated condenser unit and would simply leaving out one of the positive wires and running a neutral be ok to bring 115 volts to the new compressor motor rather than it's original 230 volts ? (allbeit using twice the amperage thus calling into question the wire sizes to the unit)