Central Heating BOILER FANS how to fix a NOISY or STUCK fan

thanks for stopping on our channel which is  dedicated to central heating and as you can see   i've been doing this a long time whether  you install or you have heating hopefully   my videos will make a difference but please  leave me a comment in the section below   likes action camera let's begin if you want to  repair boilers and do diagnostics which is a   huge demand you need a hands-on course  which we've been doing here since 2002   and it's compulsory to learn how to use the  meter and how to test components in a sequence   at the moment we're going to show you how to use  that multimeter to test the fan but you also have   to learn pumps fan sensors stats and all the other  components that make up this particular boiler   that's fallen over and we need to fix it  correctly so let's have a closer look at   using the multimeter and they fan because that's  the only way that you're going to learn on site   to test whether the windings are any good and the  other tests that i've shown you in the other clips boiler fans come in various sizes some are ac  some are dc some are a bit of each so we're going   to look at the ac ones and there are two types the  single speed 230 volts and two speed 230 volts and   we'll look at that in a little while but we also  need to find out whether the fan needs changing so   that's going to be around the year what five years  old six years old seven at the latest it needs   updated to the latest version or it's not been  maintained correctly and it's now seized up or   about to seize up and how to solve that problem so  we're going to need a good auto ranging multimeter   we're going to need some lubricants some of these  are good some of these are banned for example   so first of all let's have a look at the two  different types the single speed fan here's an   excellent example of a single speed fan and we're  going to test it with two ways firstly we're going   to spin the propeller and then secondly we're  going to measure how many ohms there are between   that neutral terminal and that live terminal  so first of all let's just do the spin test   before i can test the windings i've turned the  power off to the boiler so it's nice and dead   i've switched the multimeter onto ohms and now  we're going to do the first part of the test is   the speed so i'm just going to gently spin  it round and i can see that there's there's   no resistance there at all very carefully remove  the live and the neutral wire from the terminals   and we're going to proceed in measuring the  coil so that copper wire goes round and round   and it creates a resistance and on normal single  speed fans that number is between 20 and 120 ohms   so when i measure this i can see whether the  flue is long enough or the fan is good enough   to remove the fumes here of combustion outside  to the atmosphere and of course age has a big   play in this so first of all it doesn't matter  which terminal you use but use the holes up here   i'll do a little close-up so we use that hole  there and this hole here and then now we can   see on the display it's 44 ohms point five or six  now that movement we don't take any notice this   is a resistance value of 44 which is mid-range  because most of the single channel or single speed   fans go between 40 and 80. the slightly better  ones will be a lower number so that could be 25   to 35 would be the the best as it were in that  respect and the difference between this coil   and another one which we're going to measure is  simply the length of that copper wire and how fat   it is and also how insulated it is to stop itself  overheating so this is one test let's do another   on a two-speed fan it's just another  measurement that we have to do   to neutral so we've got two different coils  comparing it to the black lead so i've got in   touch with technical and they say mid 60s and mid  90s the first procedure as before in ohms we'll   put this one on neutral this one on here and then  we'll see which terminal this is when it comes up   it should start mounting so that's the 62  so that's the red lead and we can see the   other one should be 93 so again we'll  put it on the neutral put it on the top   press hard reasonably and then we can see here  yes it's mid 90s so therefore that's going to be   the slow speed when the gas is on low pressure  and that's how we do a double one very easy and let me show you the easy way of finding out  whether the fan needs repairing or replacing   or what's going on by that spinning test so if  we go to this one here and just give it a push   we can see that it's obviously lovely moves  gently and stops easily so let's try this one   straight away see it's stuck and the problem is this bearing here and  there's another one down below and one   here and one down below this one we can  get to very easily we can clean it out   and put some oil into it and  put it back into the boiler   whilst we wait for the latest version because once  this bearing have gone it will come back and you   can't say to the customer it might last a month it  might last six months and then it will break down   that's just not acceptable also we can't sell them  a reconditioned fan because more than likely the   factory has discontinued that model and made  a much better stronger one so we always fit   the latest version but in this particular place  what i'm going to show you is how you can maybe   keep it going for a few days or a week long  enough for the new supplied fan to arrive   so what we're going to do is try and rescue  this fan because it could be christmas   merchants are closed and we need to do something  better because it's not really good enough it's   iffy sometimes it will sometimes it won't  so here's the liquids that we need to do   etc and don't forget sewing machine oil is the  one that we're going to actually lubricate so   the procedure is very gently remove the fan from  the flue housing because it's easy to damage this   and when we spend half an hour cleaning  repairing and oiling put it back into the   boiler switch it on and it sounds like a tractor  because it's now unbalanced so always please be   careful when you remove the fan to put it onto  a nice work top so the first thing we can do is   use our wd-40 because it's a brilliant degreaser  so we can get a can of this and just put a few   drops around here and then very carefully on  the bottom bearings just a little bit here   and a little bit there nothing huge and then  with a paper towel just gently mop it up here   and mop it up there the next thing we need to  have is our favorite can of fresh air to blow that   out because it's gone into the bearings but  because it's a degreaser it doesn't oil the   spindle because it's not designed for that so we  have to get that fresh air and put it all around   here and remove as much of that wd-40 as possible  and obviously we're going to use some more of this   now we've got silicon now you would  think silicon in here was very good   but it isn't because when silicon gets hot it gets  gungy and greasy which is not a lot of good here   then we've got our favorite three in one this  is absolutely excellent for lots of things   but it has the same problem as this gets hot  it goes greasy and really thick so you can put   a few drops in here and then it will gradually  grind the fan to the pulpits so imagine this was   singer sewing machine oil here's a picture that  we've got i couldn't get one in time to make the   film and all you're going to do is to put a  couple of drops in here and just gently just   gently move it a few more drops gently gently  to get it into those bearings and you'll find   it's going to be a lot lot easier and we've got  to repeat the process very slowly at an angle   that we can just put a few drops in here to  hopefully push it down and again move the spindle   and eventually this should be more than  loose enough to put gently back into the   housing on the flue check all the seals the  washers the o-rings and the screws are perfect   plug the fan in put a cover on because when  we switch this on we want to make sure that   the tube to fire up the boiler the blowing dude  you remember that's disconnected so the boiler   doesn't fire up but we need to protect this  so you'd either wear goggles a mask or put the   cover on just so this starts working because we're  going to have oil we'll shoot all over the place   well in the fluid it's not too bad  because we can just get more tissue paper   and just clean up the mess so just be careful  when we do switch it on for the first time   without gas we just want to lubricate it wear  goggles wear a mask because it will splash   and i hope this this is giving you some ideas but  remember this is a temporary job we've got a brand   new latest version zipping through the roads all  the way to the house so that's the proper works   and now we can send this fan back to a company  that can recondition it and we've got a spare   one to lend them on the next job because we  always say if this model is going down today   there'll be others in town same age so we've got  a spare one that we can zoom off and that's how   we interchange parts as a temporary measure here's  a really good example of a manufacturer worcester   who's taken the time and trouble not  to fit just a standard single speed   but two speeds so what's the advantage as we can  see on the cutaway there's a really good reason   so the question is peoples is it for modulating  in hot water as we get here on wednesday a lot   of people say that and they could be right does  it modulate in central heating mode that sounds   logical because that's cheaper to run but the  answer is it's a time delay a lot of boilers   now a few boilers the manufacturer thinks about  the consumption of the amount of gas that this   uses and where the two-speed fan comes into  place is that there's a time delay of up to three   minutes on low gas so the fan would obviously  have to run at slow speed this particular one   is around 19 seconds and then over the next  minute it slowly increases the gas flame   until it reaches a point where the sensors  in the top send the fan into full speed and   that saves an awful lot of money and especially  people on lpg who pay their bills in gold bars   that's why this is one of the best boilers  that's ever been built on the planet one way we can measure the quality  of the fan is using air pressure   water gauges are a complete waste of  time because they're simply not accurate   we need a digital handheld one and there's also  one on your gas flow analyzer so first of all   what we need to do is to simply remove  the tube that blows which is identified   either on the air pressure switch or on  the fan and then we put our manometer   into the same hole switch on and this is going to  be one of those very rare times that we switch the   hot water on demand so the boiler can't fire up  because obviously i've disconnected it but the hot   water will send the fan into full speed whereas as  i said earlier if this was switched on in central   heating mode we could be standing here for three  minutes which is not a lot of use so now we can   see how many millibars of air pressure is being  generated by that fan and the flue and you get   that information from the factory so they should  tell you and then particularly on condensing   boilers is usually written in the manual as well  so this is a really good way of testing a fan one thing we've found out from various  organizations that occasionally   just occasionally some hero buys a can of wd-40  and they spray all over here switch the boiler on   and it explodes there's a surprise on the can  it says inflammable it is it will explode quite   happily and here's a cutaway of the instructions  where it tells you don't put it anywhere near heat   and i've seen engineers go like this and look  down around they absolutely drown it switch   it on and then whoosh some of them of course  get their eyebrows and their hair burnt out   but basically they're going to buy a new boiler  which is terrific so instead of selling a new fan   they're going to give them a brand new  boiler so there's a clever thing wd-40 is   absolutely brilliant not for fans so i hope you've  enjoyed this video please subscribe to our channel   and have a look at all my other adult videos and  any comments i'll be happy to answer take care me um hmm   so you

Channel: Mr Combi

Views: 42,490

Keywords: Y plan, S plan, no heating, PRV, cold rads, filling a combi, Vaillant, Baxi, Vokera, ideal, Glow, Danfoss, AAV leaking, no water pressure, low water pressure, Drayton, filling loop, dripping overflow, Worcester, Bosch, pump, sludge, Fernox, inhibitor, Honeywell, scale, boiler, air in rads, vent a rad, noisy boiler, Boiler Fault finding, wiring controls, Nest, Hive, zone valve, pcb test, condense pipe, Grundfos, noisy fan, Alan Hart, heating geek, test pcb, mr combi

Id: 0K68-M841RM

Length: 20min 32sec (1232 seconds)

Published: Sun Aug 29 2021