Fault Finding Webinar Highlights

good evening and welcome to this vacara barrier fault finding webinar obviously we're working with the carer components for carer boilers but most boilers operate in the same manner and we'll use similar components so this is fault finding so here's a multimeter here i try and encourage everyone to do as much testing as they can with the boiler turned off because you're simply safer infinity there's absolutely no current or voltage passing between the two probes put them together we should see zero resistance because there's nothing stopping the voltage from passing through the cling contacts and finding its way back to the meter so that's showing us 10 kilo ohms so 10 580 ohms air pressure switches i have a couple here these switches can sense eight pascals but if you must blow into them blow across the top and you can possibly hear that making and breaking but the whole of your chest isn't going into that a diaphragm if there are any calcium buildup in there and it could be much smaller than the one you can see on your right so what i'd like to do now is show you the way our water block works the movement of water that is sensed by the flow switch or flow turbine has fired the main heat exchanger up here pump has kicked in the pump is bringing down the primary flow from the main heat exchanger down this tube past the on this boiler low pressure switch the flow passes into this chamber here the diverter valve here has pulled up a cartridge here this is the heating flow that is a heating return it's pulled up a cartridge and that cartridge has blocked the heat in return so the primary flow from the main heat exchanger can't go to the radiators what it does it's a very lightly sprung non-return valve so the pump pushes the flow through that non-return valve there into the plate warming up the domestic water passing through the other side of alternate plates do you advise any silicone grease on the cartridge bit or is it just an attraction to dirt now the if you if you had a new cartridge you'd find it come in a ziploc bag and it will be pre-greased we spoke about testing motors with resistance the actuator is a motor so you can test it with one probe on the middle for the neutral test one side to the other one on this side i think this one is 800 ohms so we're getting ol so this is in the other position so i'm going to go from the other side middle to the other side there we go this is a gas valve offers current a rated boiler these will be gas valves off a b rated boiler solenoid pair here here and here they are the solenoids that lift up the two plungers that allow gas to pass through so they operate in a different way but the solenoids are tested exactly the same way they're the same solenoids these are 240 volt or 230 volt solenoids to test use the meter set for resistance pin 1 to pin 3 we'll test ev2 pin 3 to pin 4 or test ev1 pin one to pin three should give you oh let's get that there about six point four area six point four kilo ohms so that's good ev2 is okay from pin three to pin four about point eight or eight hundred ohms point eight of a kilo ohm well that's point nine that's in in uh area that's fine so if we put a probe on here probe on here this has got a resistance of 44 ohms most of ours will fall between 19 that's 1 9 and 70 ohms all the defense will have a resistance that you can relate to they're the easy ones the more tricky one is the latest style of fan and this has two connections i was told the easy way to check whether it's the fan or the board put the boiler into standby so there's no demand and we've got two sets of connections pull the control wires out because they're low voltage if the fan turns it's the board a few months after that i did exactly what i've just done here pulled the wires out fan turned must be the board so i ordered a new board put the board in same problem i ordered a new fan put the fan in boiler worked took the new board out put the old board back in boiler worked this is the culprit so i have to take it apart and look so buried in the rotor here there are tiny magnets they flash by this device here which is part of the hall effect sensor this rotates and as it spins we're getting a series of blips coming back down to the board so somewhere here or maybe in this circuitry here it's broken down so the fan motors okay the hall effect sensor had failed that's fans that just about wraps up testing components this evening from us all here at vicara from david margaret myself the team uh thanks for joining us we hope you found it informative stay safe and we hope to see you again soon at one of our webinars thank you very much good evening

Channel: Vokera by Riello

Views: 8,362

Keywords: HVAC, gas boilers, boilers, plumbing, heating, domestic heating, central heating, training, gas engineer, gas installer

Id: jcNgBUWEuWg

Length: 6min 15sec (375 seconds)

Published: Wed Jan 06 2021