eBac 2600 dehumidifier. Just stoppped collecting water.

[Jethro_uk]

Had an issue with a 3 year old eBac dehumidifier where the microswitch that senses a full/missing water container jammed, and it overflowed.

A few screws and I removed the casing, and found the problem - for some reason there was a bit of resistance in the actual switch. An eye-dropper of light oil, and it's completely free, and working as usual. It's easy to test, as the moment the water container is moved, it cuts out (you get a red light on the panel). For good measure I fitted new filters too.

However, since this, and resiting the unit, it runs as before - the humidistat seems to cause it to cut in and out. However, 4 days later, there's not a drop of water been collected in the container.

The only hint as to something is now when it's running, there's a click sometimes - like a relay somewhere is cutting in or out. Sure it wasn't there (or audible) before. It's not the switch for the fan, as the fan keeps spinning through the click.

After checking the filter and humidistat (both done) the manual goes to "request a service". This being DIY, I wondered if anyone had any ideas first ?

[Andrew Gabriel]

I am presuming this is a compressor based dehumidifier?

Did you leave it standing for 24h after moving before switching on? If it got shaken too much or tipped off vertical, it can end up pushing the motor oil into the refrigerant pipework, which can block it and, sadly, burn out the compressor. Standing allows that to drain back into the compressor sump.

Could be compressor over-current trip.

Do you have a mains power meter? If so, run it through that and watch the power consumption. The fan will be somewhere between 20-50W. The compressor will be 150-400W depending on model. Some makes have up to a 3 minuite delay before the compressor comes on (so that it won't try and start immediately after it's been switched off). The compressor may draw vastly more starting, but only for a second. If it draws something like 2-3kW just before the 'click', that would suggest it burned out and now has shorted windings. That can be as a result of switching on with oil in the refrigeration pipework.

Another possibility is the compressor capacitor has died - they're quite check to replace.

[Jethro_uk]

It has a cooling matrix like the back of a fridge, so I'm guessing yes.

Not ... as ... such :(

I'll leave it off for 24 hours, and report back.

[Peter Parry]

Leave the machine running for an hour or so, is the compressor (large black thing) very hot to the touch?

Disconnect the fan wire temporarily do you can hear the compressor over the fan noise - you should be able to hear the compressor running. If you can't and after a short time you hear a click from the relay on the compressor then the compressor has failed.

[Caecilius]

I've got a 2650e, which is probably similar.

If you remove the filter housing from the rear of the unit, the aluminium fins should feel ice cold if the compressor is running.

For another check, the power usage when the compressor is running is around 200w.

[tabbypurr]

or put a hand on the compressor, avoiding the wiring. It heats up when getting power, and vibrates when operating.

NT

[Jethro_uk]

Many thanks for all the replies.

I've now opened the unit, and can confirm that the "click" I was hearing is occurring about 2-3s after the compressor cuts in (which I felt with my hand on it).

So the question now: what (if anything) can be done to fix a ****ed compressor ?

Given that this all started after the sodding thing was moved, it's probable oil contaminated the refridgerant ? Would a "simple" regassing help ?

[Jethro_uk]

Is there anything further that can be done at this point ?

[Fredxx]

Do you feel any movement of the motor after its been left to settle for a few minutes?

Normally the whole thing is scrapped, new motor, including fitting, plus gassing usually costs more than a new one.

The oil should be miscible with the gas. If the motor runs for a few seconds before stalling them it might be the nozzle is blocked with oil.

[Andrew Gabriel]

Won't be economic if it's really that.

No

I would check the power draw when the compressor starts with a power meter, and also check the motor capacitor is OK, but most likely, the motor has overheated and now has shorted windings, which means it will draw several kW's, and trip its over current sensor (speaking as someone who did this to a freezer many years ago).

To test the capacitor, run it in series with a 100W filament lamp, and the filament should run dimmer than normal. Full brightness or nothing means the capacitor is dead. Sometimes the death is obvious if the capacitor overheated and spewed its guts out.

[tabbypurr]

Nothing. Need to determine if it really is that. It could also be a failed capacitor

I say nothing... long ago a friend had a partly shorted refrigeration compressor that ran in series with a 3kW heater, but needed a kick to get it going. How things change!

NT

[Fredxx]

What I meant to say was before turning it on again. My thoughts are, is the motor seized, or is it hydraulically locked such it will stop after a few seconds.

[Peter Parry]

Not really as the cost of repair is often greater than a new unit.

[Jethro_uk]

I'll have a go later.

I'm a little curious as to whether it would have been possible to protect the compressor from an overload with a simple trip as current drawn exceeded a threshold ? Maybe the capacitor should have blown first ? (I know it's not a fuse ...)

[Andrew]

Curious to know, Did you lay it on its side while fixing the microswitch or simply move it about ?.

My Ebac homedry was bought 2nd hand in 1988 and shipped out to Fiji and back. It weighs a ton, but has castors, and has been up and down stairs a few times but because of its weight would have been tilted 10 to 15 degrees off vertical, while bumbing from step to step, and still works fine.

Maybe this is a problem with the lastest refridgerant. Before I shipped it out, I painted all the metal panels with galvafroid paint to protect it from the very high humidity, some of which has covered the specification plate, so all I can see now is R [12 and whatever might be to the right of [12 is hidden.

[Jethro_uk]

I laid it on it's side outside, as the bottom had filled up with water :(

I then put it upright on the workbench to open up (pleasingly easy, just a set of matching screws and a little plastic manouvering).

Kicking myself that I then went an switched it on immediately.

Apart from that, it's been flawless.

[Andrew Gabriel]

Oh dear, that will do it...

That's exactly same as I did with the freezer. I did know that it had to stand before use and did leave it 24h, but that wasn't good enough after tipping on to side.

Spoke to a Hotpoint engineer afterwards who told me what I should have done, but too late by then.

[Andrew Gabriel]

The compressor has an overload trip on the side, because it expects to fail to start sometimes. To make them run efficiently, there's barely enough starting torque, and if there's still any pressure differential in the system since the last run, the compressor won't be able to start, so the trip trips out with locked rotor current after a few seconds. (That's also why some systems add a 3 minute delayed start.) After a minute or two, it cools and self resets, trying to start the compressor again.

I suspect the failure with oil getting in the wrong place is different. Compressor probably starts and runs so it's not drawing locked rotor current, but the compressor and motor rely on the refrigerent to cool them, and if the refrigerent isn't running around the system properly, motor will eventually overheat as the heat isn't being carried away to the condenser. The overheated motor suffers failure of the winding insulation, and ends up with shorted turns. From that point on, the windings will then draw much more current normal.