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Lazy-Ferret
30-05-2017, 22:15
3 years ago, we purchased a portable aircon unit for the caravan. It is 2 separate units with an umbilical cord between them, so one bit hangs outside the van, and the cord passes through the window, to the cooling unit on the inside.

It's quite a small unit, only 2400BTU, but was perfect for the ferrets, keeping their area safely cool.

This weekend the internal fan died, and upon closer inspection, I found one of the windings had burnt out. I contacted the manufacturers, to be told they do not sell spares, and as it is 3 years old, it's out of warrantee, but if I would like to send it back, they will see if it can be fixed and give me a quote!!! It weighs in at 20Kg, and is a real pig to box, so I am loathed to spend money sending it back, to then be told they want £150 or more to fix it and return it. I would rather use the money to get a new small portable domestic unit I have seen, which has higher power, and not much bigger than just one of the current units.

Looking further into it, it's a cheap Chinese unit, where anyone can order 300, and sell them under their own name, and the motor is actually produced by the same people who make the whole unit. There are no markings on the motor, other than 230V/50Hz...

So any of you guys have an idea of what sort of wattage motor I would need to drive a 230mm, 5 bladed plastic fan which has quite a steep rake on the fins.

I have been looking at other motors, but they all seem much bigger than the one that was in there, and it's a lot of money to pay out on a whim, if I have got it wrong.

Anyone help?

terranosaurusdoug
30-05-2017, 23:27
I presume it's the fan that blows cold air through and not a cooling fan for something inside, can you use an external one attatched to the outside of it, from maplins or summat :nenau

Lazy-Ferret
31-05-2017, 00:28
I presume it's the fan that blows cold air through and not a cooling fan for something inside, can you use an external one attatched to the outside of it, from maplins or summat :nenau

Yes, it's the main fan that pulls the air through the condenser, so needs to be fairly powerful. Computer fans, apart from not being big enough, tend not to like pulling air through anything, they are designed to push air.

For the weekend, we used a mains fan to push it through from the back, and a large Coleman tent battery operated fan to pull it out the other side, but not only were the fans not really up to the job, but also fans and ferrets do not mix very well... the Coleman fan has soft foam like blades, but what ever the material is, we have one ferret that wants to chew it all the time, even when it is running...:doh

solarman216
31-05-2017, 01:02
That size fan only needs about 35 watts, not sure of the physical size of yours but Elco have a range, they are about 4 inch square and vary in length depending on wattage 75 watts makes them about 4 inch cube, lower watts = shorter 35 being about 2.5 inches, if that helps, if they are near then I have several here and can post a pic, for mountings etc, Rick

Lazy-Ferret
31-05-2017, 01:13
That size fan only needs about 35 watts, not sure of the physical size of yours but Elco have a range, they are about 4 inch square and vary in length depending on wattage 75 watts makes them about 4 inch cube, lower watts = shorter 35 being about 2.5 inches, if that helps, if they are near then I have several here and can post a pic, for mountings etc, Rick

Cheers Rick.... I have ordered this (http://www.ebay.co.uk/itm/321917388460?_trksid=p2060353.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT) off of Ebay, in the hope that it will fit in there with a little work. I says it is 7/35w, but I have no idea what the two values mean. Having said that, none of the figures match up, as it says 240v, 0.25amp, but that would be 60w...

The original motor body is 83mm diameter, and 50mm front to back, excluding the shaft so in comparison, quite tiny, but it is also round, rather than square, like all the others I have seen, and fits in a recess that is exactly the right size.

If the one I have purchased does not fit the bill, I will have a look at the 35w motors.

solarman216
31-05-2017, 01:27
That is precisely the Elco multi-fit motor I was talking about, have loads of them here you could have had one for nowt, Rick

zippy656
31-05-2017, 06:14
I though of this motor... from caravan omni vent

https://www.google.co.uk/search?q=omni+vent+fan+motor&client=tablet-android-asus-rev&prmd=sivn&source=lnms&tbm=isch&sa=X&ved=0ahUKEwiO7LWfr5nUAhVoLMAKHb2KBV8Q_AUICigC&biw=1024&bih=600#imgrc=czDenAnGKR-MdM:

Lazy-Ferret
31-05-2017, 10:21
I though of this motor... from caravan omni vent

https://www.google.co.uk/search?q=omni+vent+fan+motor&client=tablet-android-asus-rev&prmd=sivn&source=lnms&tbm=isch&sa=X&ved=0ahUKEwiO7LWfr5nUAhVoLMAKHb2KBV8Q_AUICigC&biw=1024&bih=600#imgrc=czDenAnGKR-MdM:
Cheers Zippy, that looks like a potential alternative if the current plan does not work, only issue is it is 12v, not mains, but should be able to work something out... expensive though.

Sent from my SM-G930F using Tapatalk

Lazy-Ferret
31-05-2017, 10:25
That is precisely the Elco multi-fit motor I was talking about, have loads of them here you could have had one for nowt, Rick
Cheers Rick, the original fan is held on by a nut which runs down a threaded bit on the motor shaft, so that one gives me the option of a fan blade tgat I know will fit if I can't get the original one back on.

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Lazy-Ferret
03-06-2017, 15:17
Well the fan I ordered from Ebay arrived yesterday, and with a few minor modifications I got it fitted. I had to loose the adjustable fins, as the motor was much longer, but we never used them anyway.

Might need to find somewhere to regas it now though, as it does not seem to be getting as cold this year.

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solarman216
03-06-2017, 18:24
What gas Clive? Rick

zippy656
03-06-2017, 18:35
Cheers Zippy, that looks like a potential alternative if the current plan does not work, only issue is it is 12v, not mains, but should be able to work something out... expensive though.

Sent from my SM-G930F using Tapatalk

Um no!!! Just found how much!! Over 140

terranosaurusdoug
03-06-2017, 19:48
Well the fan I ordered from Ebay arrived yesterday, and with a few minor modifications I got it fitted. I had to loose the adjustable fins, as the motor was much longer, but we never used them anyway.

Might need to find somewhere to regas it now though, as it does not seem to be getting as cold this year.

Sent from my SM-G930F using Tapatalk

Nice one, I put my fan on last night and started thinking you could buy a normal cooling fan and take the motor out as they seem quite powerfull.

Lazy-Ferret
03-06-2017, 19:56
What gas Clive? Rick

I can't find anything on it specifically, but as it is only 3 years old, I would think the newer type.

The manual says...
In all air conditioning systems a small amount of refrigerant gas is lost from the system each year. When air conditioning units no longer run cold or the air from the evaporators is not as cold as you would like it is time to re-gas the system. These air conditioning systems use pneumatic tube manufactured from nylon so have a low loss of refrigerant gas. Users should not need to re-gas a unit until it is at least 3 years old.

Important EU Law put in place in 2010 to protect the environment effectively means that end users should not remove or release fluorinated refrigerant gas from air conditioning equipment. While equipment to re-gas a system is readily available from retailers the costs are prohibitive and these kits do not come with the guidance required (nor the adapter required to fit a push-on automotive service valve to the Schrader service valve on a/c units). In short – get your unit re-gassed by someone who knows what they are doing and qualified to F-Gas - C&G 2079 Cat I & II. Existing customers can bring their units to us where we will recover, re-gas and leak check their unit while they wait - please contact us if you wish to book this service.

This is what the valve looks like...

http://i316.photobucket.com/albums/mm322/Lazy-Ferret/Caravan/20170601_200153_zpshtugyunp.jpg

http://i316.photobucket.com/albums/mm322/Lazy-Ferret/Caravan/20170601_200204_zpsyaksc8lc.jpg

http://i316.photobucket.com/albums/mm322/Lazy-Ferret/Caravan/20170601_200135_zps08wdgqjf.jpg

Lazy-Ferret
03-06-2017, 20:08
Nice one, I put my fan on last night and started thinking you could buy a normal cooling fan and take the motor out as they seem quite powerfull.

That's how I started out, but I just hit one snag after another... Firstly, and quite majorly, normal fans blow the air, while the aircon unit sucks the air. I did eventually work out how the reverse the fan motor, but you can only do that on certain motors if they happen to be assembled in a particular way. Even having worked that out, I kept hitting one issue after another... like physically mounting it, in the right place, and the blades on a normal fan all seem to be either to big, or too small, finding a fan where the blades are actually 9" was not easy. I couldn't use the old fan blades, as the motor shafts on all the fans I checked out, were a lot thinner than the original one. On top of that, the cost of a reasonable fan was more than I managed to get that unit for.

I thought of using a car radiator fan, as they are nice and slim, reversible plus have all the right mountings, but not only are they very noisy, but it then opens a whole new bag of worms, as I would need a high current mains to 12v converter, and find somewhere in there to hide that...

terranosaurusdoug
03-06-2017, 20:26
That's how I started out, but I just hit one snag after another... Firstly, and quite majorly, normal fans blow the air, while the aircon unit sucks the air. I did eventually work out how the reverse the fan motor, but you can only do that on certain motors if they happen to be assembled in a particular way. Even having worked that out, I kept hitting one issue after another... like physically mounting it, in the right place, and the blades on a normal fan all seem to be either to big, or too small, finding a fan where the blades are actually 9" was not easy. I couldn't use the old fan blades, as the motor shafts on all the fans I checked out, were a lot thinner than the original one. On top of that, the cost of a reasonable fan was more than I managed to get that unit for.

I thought of using a car radiator fan, as they are nice and slim, reversible plus have all the right mountings, but not only are they very noisy, but it then opens a whole new bag of worms, as I would need a high current mains to 12v converter, and find somewhere in there to hide that...

Yeh my fan was quite cheap I think I got a deal on it, however it is a good one and probably cost a fair bit more today, messing about with converters etc gets messy and you end up with franken-con in your van, glad you got that bit sorted and if rick can't sort the gas out I'll eat my underpants :D

solarman216
03-06-2017, 21:30
Re the gas Clive there are several "newer" gasses but they are not compatible with each other so you have to identify the exact gas, and if it is one of the type to be charged in the liquid phase only, then it needs to be de gassed and recharged completely, this is because they are a mixture of two or more gasses and if the leak was/is of the gas phase then you have no way of knowing which gas you have lost, Rick

Lazy-Ferret
03-06-2017, 21:37
Re the gas Clive there are several "newer" gasses but they are not compatible with each other so you have to identify the exact gas, and if it is one of the type to be charged in the liquid phase only, then it needs to be de gassed and recharged completely, this is because they are a mixture of two or more gasses and if the leak was/is of the gas phase then you have no way of knowing which gas you have lost, Rick

That makes sense, they do say it has to be drained, vacuum down, and then re-charged.

Because it is effectively 2 units joined by an umbilical cord, they say that the nylon pipes naturally leak off over time, so I guess it would be just the gas that is lost tough. I wonder how I find out which gas it has... looks like a bit more RTFM'ing... LOL

solarman216
03-06-2017, 22:51
That makes sense, they do say it has to be drained, vacuum down, and then re-charged.

Because it is effectively 2 units joined by an umbilical cord, they say that the nylon pipes naturally leak off over time, so I guess it would be just the gas that is lost tough. I wonder how I find out which gas it has... looks like a bit more RTFM'ing... LOL

Just as important Clive is there a various oils, wrong gas with wrong oil = no more AC unit, look on the compressor if there is no outside label, it will be R134a/R404/R407/or R410a but the last one is doubtful as your charge point does not look big enough, I have the other three gasses, Rick

Lazy-Ferret
04-06-2017, 15:42
Just as important Clive is there a various oils, wrong gas with wrong oil = no more AC unit, look on the compressor if there is no outside label, it will be R134a/R404/R407/or R410a but the last one is doubtful as your charge point does not look big enough, I have the other three gasses, Rick

Just found the manual, and it says R134a 220gr, which I guess means it takes 220grams of the stuff.

terranosaurusdoug
04-06-2017, 16:13
Just found the manual, and it says R134a 220gr, which I guess means it takes 220grams of the stuff.

:clap:thumb2 nice one fella, you've nailed now :D