ProDave Posted March 16 Share Posted March 16 I have been aware of my ASHP getting more noisy than usual all winter. When a passing neighbour enquired today what the noise was, I thought it was time to have a look. It is the fan motor looks to have failing bearings. It's a sort of high pitched whine sound that varies with fan speed. It is not the compressor, that purrs as quiet as a quiet thing. So probably time to start looking for a sollution. Here is the fan motor: Googling the part number FMEC531LGB and the motor is available, most places seem to be charging between £250 and £300 but Alibaba have it for £150 with postage https://www.aliexpress.com/i/1005003764026412.html I'm torn between buying a new motor, or trying to replace the bearings in the one I have. Trouble with that is it will take time to dismantle it, find the bearings, order them etc, all the while the ASHP will be out of action so that will have to wait until we have finished with heating. Or I might buy a new motor and then look at fixing the old one as a spare. I have not yet found anyone dismantling this exact motor so have no clue if it is easy or hard and if the bearings are obtainable. Link to comment Share on other sites More sharing options...
joe90 Posted March 16 Share Posted March 16 Gosh you have not had it very long (IMO), as you want to stay there (I presume) buying a new motor and servicing the existing one as a spare sounds like a plan. 1 Link to comment Share on other sites More sharing options...
ProDave Posted March 16 Author Share Posted March 16 The HP was installed in mid 2018, so coming up to 6 years old. Yes it is disappointing but it has not yet "failed" I am hoping someone else who has had one fail might find this thread and let me know where they got a replacement, or did they replace the bearings. I have never used Alibaba so not sure whether to trust them or not, the worry being in some way it may not be the right thing and resolving that may not be easy. I generally only buy really cheap stuff from China on the basis I can afford to lose the money if something goes wrong. 1 Link to comment Share on other sites More sharing options...
sharpener Posted March 16 Share Posted March 16 1 hour ago, ProDave said: I'm torn between buying a new motor, or trying to replace the bearings in the one I have. I would expect them to be industry standard bearings and you can probably get them from simplybearings.co.uk, they may even know what it is you need. I fitted their SKF bearings to the AEG motor in my oil boiler. It was quite easy to dismantle and obvious how to fit the replacements, just needed a wooden drift of about the right size, it has been running OK for two seasons since I did it. So that would be the way to go IMO once you don't need the heating for the summer. Link to comment Share on other sites More sharing options...
ProDave Posted March 16 Author Share Posted March 16 Yes I am leaning that way. There was only 1 review of the motor on alibaba and that was to say it arrived broken and they were not interested in resolving that. That does not encourage me to buy from there. My thinking is once the heating season is over I should be able to remove it, open it up, identify the bearings and put it back together in a day. IF anyone has replaced this motor and has the old one I would be interested in that to repair it off line so to speak? Link to comment Share on other sites More sharing options...
dpmiller Posted March 16 Share Posted March 16 A shot of spray grease in the general direction of the front bearing might be worth a try, in the short term at least? Link to comment Share on other sites More sharing options...
JohnMo Posted March 16 Share Posted March 16 Noticed a few fan motors on eBay, may be worth asking for the part number... 2 hours ago, ProDave said: fan motor looks to have failing bearings. Link to comment Share on other sites More sharing options...
joe90 Posted March 16 Share Posted March 16 3 hours ago, ProDave said: FMEC531LGB Link to comment Share on other sites More sharing options...
joe90 Posted March 16 Share Posted March 16 Question @ProDave, how long would it take to remove motor, remove bearings and measure them with a vernier, then put bearings back in and re fit ? A few hours 🤷♂️Then find supplier for new ones (I have used simply bearings in the past for various replacements). Link to comment Share on other sites More sharing options...
ProDave Posted March 16 Author Share Posted March 16 1 hour ago, joe90 said: Question @ProDave, how long would it take to remove motor, remove bearings and measure them with a vernier, then put bearings back in and re fit ? A few hours 🤷♂️Then find supplier for new ones (I have used simply bearings in the past for various replacements). That's the plan but I would rather wait a few weeks until we are done with heating so there is less pressure in case something goes wrong. From what I know of this motor is the main body is plastic. The front where the spindle emerges is a metal plate held on by I think by 4 screws. I suspect the front bearing might be easy to access, but I suspect the rear bearing is pressed into the plastic housing so may be harder to extract and replace without breaking something. Disappointing that unlike other motors there are no details yet emerging of anyone repairing one. 1 Link to comment Share on other sites More sharing options...
HughF Posted March 17 Share Posted March 17 I would imagine a standard fan motor from any other heat pump would work just the same…. As long as it was a three phase one (which they all are these days being variable speed). Link to comment Share on other sites More sharing options...
dpmiller Posted March 17 Share Posted March 17 1 hour ago, HughF said: I would imagine a standard fan motor from any other heat pump would work just the same…. As long as it was a three phase one (which they all are these days being variable speed). except it's not 3ph. It's 310VDC plus an enable and a speed control input? Link to comment Share on other sites More sharing options...
HughF Posted March 17 Share Posted March 17 33 minutes ago, dpmiller said: except it's not 3ph. It's 310VDC plus an enable and a speed control input? Sorry, bad choice of terminology on my part/lack of bother to explain myself properly. It’s 3 phase from a vfd at varying frequency. It’s not DC. you could swap any brushless fan motor from an aircon unit into it and I bet the fan driver wouldn’t care. Link to comment Share on other sites More sharing options...
HughF Posted March 17 Share Posted March 17 (edited) 7 minutes ago, HughF said: Sorry, bad choice of terminology on my part/lack of bother to explain myself properly. It’s 3 phase from a vfd at varying frequency. It’s not DC. you could swap any brushless fan motor from an aircon unit into it and I bet the fan driver wouldn’t care. Seems there are both types available…. Daikin also seem to use one that does indeed have the controller in the fan motor. all the ones I’ve seen have had UVW terminals coming out the side, hence my earlier assumption/statement. Edited March 17 by HughF Link to comment Share on other sites More sharing options...
ProDave Posted March 17 Author Share Posted March 17 The motor connections can be seen on my original picture if you enlarge it: RED: YM 310V DC That will be the main power (rectified 220V ac gives about that, it will be a bit over in the UK) Blue: GND I take that as power ground. Brown: VCC 15VDC I take that as power for the control electronics inside the motor. White: FG Functional Ground? Ground for the control electronics? Orange: 0-6.0VDC Probably speed demand input Violet: Reverse logic signal to tell it which way to rotate. When I do get around to opening the motor, I will take pictures. Link to comment Share on other sites More sharing options...
Simon R Posted March 17 Share Posted March 17 17 hours ago, ProDave said: I am hoping someone else who has had one fail might find this thread and let me know where they got a replacement It may be worth considering an outfit like Beastons https://www.beatson.co.uk/ they do all sorts of fan work. Link to comment Share on other sites More sharing options...
Strangey71 Posted April 13 Share Posted April 13 I would think you have probably already done this but it has worked for me on some of these issues where you think 'I would just like to know someone has done this before, and you can do it relatively easily' Have you tried searching on Youtube, Instagram and Facebook for tutorials of any kind, sometimes putting wildly different search criteria works well. Sorry if I am suggesting the obvious, just may be worth trying first. Link to comment Share on other sites More sharing options...
ProDave Posted April 13 Author Share Posted April 13 No not done it yet. Up until a day or 2 ago we have had some lousy wet cold windy weather. Plus I have been quite busy. I have been waiting for a weather window where I can be certain it is going to be dry the whole day so I can dismantle it without pressure to get it done in a hurry. Unfortunately the next 7 days forecast on XC weather all show rain. It is a good job I am not in a hurry. Heating is off now (at last) and it is only running for DHW now. Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now