D
Dotty
For hints, tips and secrets of boiler breakdowns.
Welcome to the forum. Although you can post in any forum, the USA forum is here in case of local regs or laws
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Whyme
Posted before but if you have a glowworm cxi and the fan pulses on and off along with the display after working on it ...get a hairdryer and heat up the pcb because theres a dodgy capacitor on the board that freaks out when cold......i thought tech were winding me up but it works. (if it doesnt the pcb's knacked).
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Whyme
Fit a vailant 937 recently and when the cold tap was turned on the boiler pump would kick in but not fire, like if a hot tap had been opened briefly...apparantly the aquasensor picks up negative pressure sometimes even through the cold so..get to the diagnostics by pressing the i + - buttons simultaneously. To access the second level diagnostic codes scroll through to D.97 press the i button scroll to 17. Press and hold the i button untill it returns to D.97. Then you wil be able to access second level diagnostics.....D.88 (adjust the sensitivity of the aqau sensor for water hammer..0=1.5l/min and no delay..1=3.7l/min with 2s delay........i adjusted with a delay, Good times..
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neily01
Vokera Unicas and mynute he fault code 73 return thermistor faulty. The return thermistor will have corroded because the silly clip holding the flue thermostat to the conveyor has cracked the conveyor. New conveyor and thermistor easy enough done.
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R1CKY
If you've narrowed down a fault to two suspect components, the faulty one will be the one you choose not to order.
Strange intermittent fault on an Ideal Icos/Isar/Istore? Check the rear of the heat exchanger, they tend to melt and can play buggery with the wiring loom.
Ferolli Modena 102 and similar firing up for seconds at a time with NO DEMAND is caused by faulty thermistors usually. Doing the same with demand, is usually caused by the venturi failing. DO NOT REMOVE unless you are 100% sure or have a replacement, 9 times out of 10 it will turn to a little pile of dust as soon as you touch it!
Ariston Microgenus, usually give a fault code relating to the air pressure switch, most of the time its the fan. They seem to be running perfectly, but they slow down with age and don't spin fast enough to operate the APS.
Strange intermittent fault on an Ideal Icos/Isar/Istore? Check the rear of the heat exchanger, they tend to melt and can play buggery with the wiring loom.
Ferolli Modena 102 and similar firing up for seconds at a time with NO DEMAND is caused by faulty thermistors usually. Doing the same with demand, is usually caused by the venturi failing. DO NOT REMOVE unless you are 100% sure or have a replacement, 9 times out of 10 it will turn to a little pile of dust as soon as you touch it!
Ariston Microgenus, usually give a fault code relating to the air pressure switch, most of the time its the fan. They seem to be running perfectly, but they slow down with age and don't spin fast enough to operate the APS.
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neily01
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neily01
Not quite the same but will go with it,poor hw with gled hill 2000 keep pressing sw2 button at the top of pcb until hw temp value is being read. If it reads h85 and the plate is cold then new hw thermistor required.
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Whyme
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neily01
Sorry missed that vaillant water pressure switches detect system pressure but also look for a 0.3 bar spike when the pump first kicks in, if it doesn't detect the spike thinks its a pump failure. So if the pumps running but getting f75 it's a blocked up pressure sensor. Bad position on the old models bottom left now top left on the new models.
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R1CKY
Ahh Gledhill! If you are ever unfortunate to come across a Gledhill Gulfstream, turn around and walk away! I'd rather try and resolve the North Korea crisis that work on one of those abortions!
DHW diaphragm on a Gionnani diverter valve not making contact with the microswitch, bit of plumbers mait and a 5p coin stuck to the top hat on the pin works as great temporary fix until you can make a permanent repair.
Heatline Vizo and similar. Hot water not working will most likely be caused by the diverter cartridge leaking into the motor. Turn the power off at the mains before you touch it, as they can blow fuses on the board, sometime the board itself, when they are moved with water in them.
DHW diaphragm on a Gionnani diverter valve not making contact with the microswitch, bit of plumbers mait and a 5p coin stuck to the top hat on the pin works as great temporary fix until you can make a permanent repair.
Heatline Vizo and similar. Hot water not working will most likely be caused by the diverter cartridge leaking into the motor. Turn the power off at the mains before you touch it, as they can blow fuses on the board, sometime the board itself, when they are moved with water in them.
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Dotty
Changing one of these on Monday. Vaillant also say there is a filter that can be accessed and cleaned if you remove the rubber flow hose.
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Whyme
if its an old one the part will be on the bottom left in the brass block "rubber hose type". ifs its newer it will be behind the air exhaust to the left just before the pipe goes into the main heat ex " copper connections no rubber hoses"...its a black part that has a little pin plug attached..if you undo the rubber flow hose then make sure youve got a jubilee clip to make good after. (just crunch the hoses croppie to get rid of the crap around the system).
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Whyme
How do ya get your words so small its like your whispering..lol
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neily01
Ideal optia,basically a early condensing classic. Water staining and rusting on the inside of casing running down centre of the boiler. HAd two o these with good fga readings of about 20ppm co and 0.00 ratio so thought it could not be inner flue! Wrong! break the top section of secondary hex and withdraw to find the pipe adaptor corroded through leaking all over the back of boiler. God knows how the fga wasn't going crazy?
Gloworm betacom 24/30c short cycling..... Check flame electrode hasnt bent into burner so flame isnt recognised.
No ignition on ferroli tempra, remove a wire from aps and if fan kicks and ignition commences in you know you have a sticking aps.
No ignition on ferroli tempra, remove a wire from aps and if fan kicks and ignition commences in you know you have a sticking aps.
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shaunsinky
IDEAL LOGIC+ you can find the last 10 faults and also current reading, flow rates, temperatures etc in the installer settings.
all you have to do is turn both dhw and ch potetiometer knobs to minimum and hold the reset for about 2 seconds
all you have to do is turn both dhw and ch potetiometer knobs to minimum and hold the reset for about 2 seconds
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Dotty
Found out today Vaillant do an F75 kit which moves the sensor from the flow to the return just after the pump.
It's about £120.00
Should be free!
B
Billy Bob Bob
baxi 105/24,instants,performa,main 30-24 all HE VARIANTS NOT SE
flame failure light intermittent,fan fault neon on 99% aps has failed or rubber boot on combustion box cracked
pump pressure switch illuminated,pin not lifting,its normally a blocked hole under the diaphragm at fault
no ignition aps or gas valve multiplug fault
cant keep water in it gauge drops instantly,HE hex split,check condy pipe with the boiler off water going down confirms it
heating fault gets up to 60 degrees,kettling ,shuts down,thermistor reading 11k when cold,return filter blocked
fan noisy-plastic boots on plugs faulty does sound like the fans going
baxi duotec1/HEA,plat1,potterton gold,tit,heatmax,promax
E168 pcb internal coms failed,as a temp fix remove all the plugs,have a cuppa,re fit plugs,re set it,will add more as time allows
flame failure light intermittent,fan fault neon on 99% aps has failed or rubber boot on combustion box cracked
pump pressure switch illuminated,pin not lifting,its normally a blocked hole under the diaphragm at fault
no ignition aps or gas valve multiplug fault
cant keep water in it gauge drops instantly,HE hex split,check condy pipe with the boiler off water going down confirms it
heating fault gets up to 60 degrees,kettling ,shuts down,thermistor reading 11k when cold,return filter blocked
fan noisy-plastic boots on plugs faulty does sound like the fans going
baxi duotec1/HEA,plat1,potterton gold,tit,heatmax,promax
E168 pcb internal coms failed,as a temp fix remove all the plugs,have a cuppa,re fit plugs,re set it,will add more as time allows
Not really a fault as such but if you get asked to service a powermax (the older version 155 i think) take the burner gaskets with you and take the burner out. 9 times out of 10 the baffels in the heat exchanger have fallen to bits. They are about £17 each and there are 8 of them. (read in manuall you are suposed to replace the baffels every 2 years!) To remove once cracked you have to remove the sump and its a good few hours. Boiler classed as ID. The last 3 powermax boilers I have serviced have all resulted in winning new boiler changes.
Biasi 24s/m96 unusual one I had. Boiler intermittantly cuts out on temperature and wont reset but does not lock out. The green led flashes fast allowing you to go to diagnostic mode by flipping the dip switches on the PCB. Check BP on heating, ramps up to full and goes out on temperature. Heating NTC at fault.
Biasi 24s (older one) no heating, hot water okay. Heating fires up briefly then goes out indicating a flow fault. If fuse spur is turned off on this model you sometimes need to push up one of the dip switches on the PCB and leave for 10 mins, then flick back. Only found out from technical but have since had this fault twice. Then the heating stays on and works fine.
Biasi 24s (older one) no heating, hot water okay. Heating fires up briefly then goes out indicating a flow fault. If fuse spur is turned off on this model you sometimes need to push up one of the dip switches on the PCB and leave for 10 mins, then flick back. Only found out from technical but have since had this fault twice. Then the heating stays on and works fine.
Some of the guys in work checked with Powermax and they said that it's only NCS if the baffles aren't replaced as long as it isn't having an effect on combustion as they are only there to make the boiler a bit more efficient.
Also, you can sometimes get away with getting some condensate pipe and pushing it down on to the broken baffles at the bottom and then they'll pull out with the condensate, and you can get some really long nose pliers - never work on Powermax myself but the guys that do never seem to remove the sump to remove the old baffles.
Ariston Clas HE - If there's been a power cut it can sometimes cause the PCB to lose it's memory, if you look in the manual, there's a ridiculous amount of parameters - go through them all and make sure they are correct or the boiler will be causing all sorts of problems.
When I spoke with Baxi tech regarding the broken baffels they said it is classed as ID (not that they seem to know much themselves about these boilers) as they are there to slow the gasses down and it would effect the flame. I have replaced the baffels before by pulling them through the bottom but the time it takes to do that and the cost of them makes it seem like a bad choice in my opinion. Plus the fact that if you leave a powermax turned off for more than a day several components seem to fail at once for some reason.
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Whyme
If you fit a vaillant and theres no display and not working on initial fireup. dont get carried away and start swapping pcbs/display boards. Check the pressure sensor (slug) by unplugging it and replace. Dont know why faulty slugs cause this but they can..
Ravenheat CSI 85at, pump running, but nothing else - primary ntc sensor or the loom to it are no good.
Same boiler as above. Boiler lights, but goes out again - bad connection on condense trap. Cut it off and join the PCB end to the spark end.
Same boiler as above. Boiler lights, but goes out again - bad connection on condense trap. Cut it off and join the PCB end to the spark end.
Worcester greenstar
If fan fails to pulse after power up. It usually points to fan failure
From memory you need to check for 240v on purple wire. But if no pulse it's usually dead
If fan fails to pulse after power up. It usually points to fan failure
From memory you need to check for 240v on purple wire. But if no pulse it's usually dead
Fan running constant on a FAN modulation boiler - ideals isar, etc, Worcester greenstar, etc... Usually points to fan failure
It's a failure of the tacho PCB on the fan and it can't regulate the fan speed
It's a failure of the tacho PCB on the fan and it can't regulate the fan speed
Poor flame on pilot
If the flame is not a pronounced crisp blue flame on the pilot then then injector is usually on the way out.
You shouldn't try and. Clear this with a pin Etc. you should always replace
If the flame is not a pronounced crisp blue flame on the pilot then then injector is usually on the way out.
You shouldn't try and. Clear this with a pin Etc. you should always replace
FOR COMMERCIAL
If visiting a Hamworthy boiler with a HSI
You must check the resistance in ohms.
It must be between 80-120 ohms. Of it is outside of this range it is prob on its way out. But also it may cause PCB damage
If visiting a Hamworthy boiler with a HSI
You must check the resistance in ohms.
It must be between 80-120 ohms. Of it is outside of this range it is prob on its way out. But also it may cause PCB damage
ideal classic
If you find the boiler lighting and then going out within a few seconds.
The fault is not always linked to the flame dectection. It is mostly linked to the APS.
Give the fan a good clean and the heat exchanger and this should cure the problem
If you find the boiler lighting and then going out within a few seconds.
The fault is not always linked to the flame dectection. It is mostly linked to the APS.
Give the fan a good clean and the heat exchanger and this should cure the problem
Potterton prima, pilot lights then clicks constantly without going to main flame. Pcb, aps and slow fan can cause this. Also seen the tubes to the aps becoming hard and blocking the air flow to the aps. Usually when you drop the pcb housing it kicks in. Also check for the housing pressing on the overheat stat and causing a false reading.
Baxi Duo Tec HE or HEA/Potterton Promax Combi HE or HEA/Main Combi HE or HEA.
The serial numbers on these boilers all begin with 3 letters, followed by some numbers. The first 2 numbers are the build year, the second 2 the build week. The rest are random. So for example, a 28 HE A Duo Tec built in the 23 week of 2010 will be CAC1023XXXXXXX.
E119 - Low water pressure - Look for water leak coming from the water pressure switch of the diverter valve spindle. Also check and re-charge the vessel if required.
E133 - Failure to ignite - On older models built pre 2010, the ignition electrodes warp with the heat. They are now re-designed and much better. As a temporary fix, bend them back to make the gap the thickness of a pound coin.
E131 - (not listed) - Can be caused by a few things, sometimes if 2 fault codes come up together, such as E133 (failure to light) then E119 (low system pressure). It can also be caused by power failure during fault code.
E168 - Communication Error (not listed) - Most likely the PCB. Check the voltage and polarity before ordering a replacement.
E160 - Fan fault - Most of the time the fan is faulty. Check the loom to it. If you unplug the rectangular connector block, the fan should run at fall speed. If it doesn't and there's power going to the fan, it is definitely goosed.
E20 - CH NTC sensor fault - Most likely needs replacing. Check resistance on the pins, it should be about 10k when cold.
E50 - DHW NTC sensor fault - Most likely needs replacing. Could have been caused by a leak from it's gasket. It can then corrode the sensor and the loom. This fault should still provide CH, just not DHW.
E110, E125 and E193 - Circulation fault - Pump could be seized or faulty. Also worth checking is the filter located in the return isolation valve behind the blanking cap or (if fitted) the integral filling loop.
Another fault that I have come across a couple of times is with boilers fitted with a verticle flue. The boiler doesn't provide enough hot water. When it fires up, the boiler becomes noisy and eventually goes out. Check the air intake side on the flue test point. If the CO rises the plastic flue exhaust could well be cracked. You'll have to pull the flue apart to check it.
The gas valve on these boilers also need adjusting, the CO2% should be 8.7 on high and 8.4 on low. Adjustment is made on the front of the gas valve, the throttle for high is behind the blue cap, the offset on low is behind the brass flat headed cap. You'll need some Allen keys to do the adjustment. The throttle is a small allen key, the offset slightly bigger.
To ACCESS SERVICE MODE - Turn the potentiometers to min, then turn the DHW potentiometer to the 3 o'clock position and back to the 12 o'clock position twice. The display should change briefly to SF, the LEDs flash and the boiler should light up. Turn the CH potentiometer to MAX (will display 00) for max fan speed and turn back down to MIN for minimum (will display 0). The temp should then cycle with the letter P. To get out of service mode, turn the DHW potentiometer to any position from 12 o'clock (min).
The serial numbers on these boilers all begin with 3 letters, followed by some numbers. The first 2 numbers are the build year, the second 2 the build week. The rest are random. So for example, a 28 HE A Duo Tec built in the 23 week of 2010 will be CAC1023XXXXXXX.
E119 - Low water pressure - Look for water leak coming from the water pressure switch of the diverter valve spindle. Also check and re-charge the vessel if required.
E133 - Failure to ignite - On older models built pre 2010, the ignition electrodes warp with the heat. They are now re-designed and much better. As a temporary fix, bend them back to make the gap the thickness of a pound coin.
E131 - (not listed) - Can be caused by a few things, sometimes if 2 fault codes come up together, such as E133 (failure to light) then E119 (low system pressure). It can also be caused by power failure during fault code.
E168 - Communication Error (not listed) - Most likely the PCB. Check the voltage and polarity before ordering a replacement.
E160 - Fan fault - Most of the time the fan is faulty. Check the loom to it. If you unplug the rectangular connector block, the fan should run at fall speed. If it doesn't and there's power going to the fan, it is definitely goosed.
E20 - CH NTC sensor fault - Most likely needs replacing. Check resistance on the pins, it should be about 10k when cold.
E50 - DHW NTC sensor fault - Most likely needs replacing. Could have been caused by a leak from it's gasket. It can then corrode the sensor and the loom. This fault should still provide CH, just not DHW.
E110, E125 and E193 - Circulation fault - Pump could be seized or faulty. Also worth checking is the filter located in the return isolation valve behind the blanking cap or (if fitted) the integral filling loop.
Another fault that I have come across a couple of times is with boilers fitted with a verticle flue. The boiler doesn't provide enough hot water. When it fires up, the boiler becomes noisy and eventually goes out. Check the air intake side on the flue test point. If the CO rises the plastic flue exhaust could well be cracked. You'll have to pull the flue apart to check it.
The gas valve on these boilers also need adjusting, the CO2% should be 8.7 on high and 8.4 on low. Adjustment is made on the front of the gas valve, the throttle for high is behind the blue cap, the offset on low is behind the brass flat headed cap. You'll need some Allen keys to do the adjustment. The throttle is a small allen key, the offset slightly bigger.
To ACCESS SERVICE MODE - Turn the potentiometers to min, then turn the DHW potentiometer to the 3 o'clock position and back to the 12 o'clock position twice. The display should change briefly to SF, the LEDs flash and the boiler should light up. Turn the CH potentiometer to MAX (will display 00) for max fan speed and turn back down to MIN for minimum (will display 0). The temp should then cycle with the letter P. To get out of service mode, turn the DHW potentiometer to any position from 12 o'clock (min).
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JBP Heating
Ideal isar/icos HE. If the boiler lights ok from cold but goes to LF during ignition when boiler is warm check the spark generator. Check for correct DC voltage into the generator and if there is a spark at the electrode. These generators can develop a fault where they only fail when warmed by the ambient heat inside the boiler.
Have changed lots of powermax baffles there are whole estates of them round here and very few have been reg serviced so almost always have the baffles corroded and dropped inside the heat exchange tubes. I use a flexible nylon cable pulling rod to get them out. With the sump off push the cable rod past the baffle in the tube reach under the tank in to the sump hook the cable rod hook over the bottom edge of the baffle and pull out the cable rod from above. Hey presto your baffle is out and you can give the tube a good brushing.
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julesverne
common problem always asked in the private forum vokera boiler only firing when cover taken off. always a partially blocked venturi or has been in my case.
I
IDCHAPPY
If you're topping up the pressure on a glowworm 30cxi best to do it slowly as they have a tendency to spit out the return filter beside the pump 🙁
Vaillant Eco tec plus 2 (new ecotec)
F70
Check coding resister (on harness right hand side of main heat x)
Check gas type plug on pcb
Check all cable plugs for poor connections.
Check plugs with any faults. female connections spread open causing poor contacts.
F70
Check coding resister (on harness right hand side of main heat x)
Check gas type plug on pcb
Check all cable plugs for poor connections.
Check plugs with any faults. female connections spread open causing poor contacts.
K
Koogatubac
B
buckley plumb
Glow worm cxi no display or lights board check.
If there is no display, there are some other things ratherthan the boards which can take the display out.
Any of the low voltage components can also do that, so wealways say to disconnect the 3 connections on the left hand side, J1 J4 and J2and see if the display comes back, if it doesn't then you need to ease J13 offthe top centre so you can see the metal tracks underneath, and see what voltageyou are getting on the first track on the right hand side. It should be reading15-16 volts DC, this is the feed to the display board by the main board so ifyou are not getting that then it is the main board, if you are then it is thedisplay board.
Most of the time we do recommend in changing them bothtogether as some of the new software doesn't always like the old software, soeven if if you do or don't get the voltages it still might need both boardsreplacing.
If there is no display, there are some other things ratherthan the boards which can take the display out.
Any of the low voltage components can also do that, so wealways say to disconnect the 3 connections on the left hand side, J1 J4 and J2and see if the display comes back, if it doesn't then you need to ease J13 offthe top centre so you can see the metal tracks underneath, and see what voltageyou are getting on the first track on the right hand side. It should be reading15-16 volts DC, this is the feed to the display board by the main board so ifyou are not getting that then it is the main board, if you are then it is thedisplay board.
Most of the time we do recommend in changing them bothtogether as some of the new software doesn't always like the old software, soeven if if you do or don't get the voltages it still might need both boardsreplacing.
Vaillant 824e Turbomax Plus comes up with fault code F28. Did all my resistance and voltage check and still nothing happening. It goes all the way to ignition but does not fire. Hence decided will go next day with a new gas valve, turned up next day without one just wanted to check what could be wrong, when I took it out it had water in it. Don't know how it got in there. But after drying it out everything working perfectly fine. Saved few bobs for the customer and earned few more for myself.
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I went to a ferrolli optimax he locked out on f37 low pressure there was presure in it and no blockage to the low pressure switch changed the low pressure switch still the same spoke to ferrolli it's no low pressure it's caused by a power surge to the board to get it to reset " press reset for 10 sec wait for ts,press reset and let go immediately it will show p1, press bottom + once p2 will display, press top - to go back to p1, 00 will appear( it needs to be 01) use top + &- to change then press the bottom + once to back to p2, then press top + and 01 should be displayed then press and hold reset for 10 sec and it should be reset! Hopefully will save someone 40 quid for a Low pressure switch
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Whyme
before you start any fault finding check the three esentials
pressure
is there water in the boiler dont trust the guage whack half a bar in ive had many gauges reading 1bar when theres realy nothing in it
power
is there power to the boiler
gas
is there definatley gas at the boiler once spent 20 mins to find a fault and the the gas valve under the boiler was in the off position always best to crack a union or put a guage on
pressure
is there water in the boiler dont trust the guage whack half a bar in ive had many gauges reading 1bar when theres realy nothing in it
power
is there power to the boiler
gas
is there definatley gas at the boiler once spent 20 mins to find a fault and the the gas valve under the boiler was in the off position always best to crack a union or put a guage on
E
Ermintrude
Had same on a duo tec , ages checking then thought would check outlet at meter ... 3mb
If you get a leak from the tube where flow turbine is on Greenstar, usually the adaptor behind the turbine has disintegrated.
If you can't get the temp to ramp to max on a Flexicom, then before getting multimeter out etc, take out and clean condense thoroughly. Trap, flush through HEX and check pipe is clear. Had this twice passed on from other company's unable to fix with thermistors. :thinking:
Intermittent ignition on a Solo/Promax. If it's on the new style all in one PCB then when it's lit, tap the PCB housing near yellow sticker. Can get it to drop out if PCB is at fault.
Glowworm CI, if you are getting PCB error as fault code (F13??) then check APS is not stuck on before fan has run, as it throws up PCB error.
If you can't get the temp to ramp to max on a Flexicom, then before getting multimeter out etc, take out and clean condense thoroughly. Trap, flush through HEX and check pipe is clear. Had this twice passed on from other company's unable to fix with thermistors. :thinking:
Intermittent ignition on a Solo/Promax. If it's on the new style all in one PCB then when it's lit, tap the PCB housing near yellow sticker. Can get it to drop out if PCB is at fault.
Glowworm CI, if you are getting PCB error as fault code (F13??) then check APS is not stuck on before fan has run, as it throws up PCB error.
If you goto an ecotec pro/plus that is starting up when switched on and display fades and the boiler conks out....check to see if pressure switch is the pink one and replace this first as it could be drawing all the power away from the rest of the boiler....had one yesterday.
For gledhill pulsacoil 3 also check that the little float switch in header tank hasn't been broken off/that it makes a connection to send power to the board, no power will go to immersions if it is not making a connection.
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Biasi M96(24/28)SM/C2
Round black APS
boiler fires up for a few seconds then goes off, continues to spark. After a few attempts the lock out led comes on. Works when the combustion chamber is off.
check flue was fitted correctly as the white seal bends when pushing the elbow into the flue and doesn't sit right.
Fault only starts after the warrenty period is over 🙁
Remove the complete flue clean and pour water in the top of the boiler to clean out the heat exchanger. Done 3 of these in the past year.
Round black APS
boiler fires up for a few seconds then goes off, continues to spark. After a few attempts the lock out led comes on. Works when the combustion chamber is off.
check flue was fitted correctly as the white seal bends when pushing the elbow into the flue and doesn't sit right.
Fault only starts after the warrenty period is over 🙁
Remove the complete flue clean and pour water in the top of the boiler to clean out the heat exchanger. Done 3 of these in the past year.
D
dave1
Got one of these that displays aps fault mostly in ch mode. New aps fitted already, I'm going too go back and check flue and Venturi. Any other ideas?
Worcester Greenstar 28i Jr
If your customer is getting below/above average heat on the DHW hold fire on the PHE for a second & get out your thermometer & multimeter.
Check the resistance on the DHW NTC, for example I had a GS 28i JR that was not getting past 40C @ the DHW outlet the Kohms reading was out by 0.5
10C - 19.9 Kohms
20C - 12.3 Kohms
30C - 7.9 Kohms
40C - 5.2 Kohms
50C - 3.5 Kohms
60C - 2.4 Kohms
70C - 1.7 Kohms
If your customer is getting below/above average heat on the DHW hold fire on the PHE for a second & get out your thermometer & multimeter.
Check the resistance on the DHW NTC, for example I had a GS 28i JR that was not getting past 40C @ the DHW outlet the Kohms reading was out by 0.5
10C - 19.9 Kohms
20C - 12.3 Kohms
30C - 7.9 Kohms
40C - 5.2 Kohms
50C - 3.5 Kohms
60C - 2.4 Kohms
70C - 1.7 Kohms
Captain.rick
Gas Engineer
Here's 1 for commercial oil burners. I'd say Croppie's seen this. Have seen this happen a couple of times on Riello RL burners.
If the plant room door is open on a sunny day, sun shining in can make d burner go to lock out.
Photocell can pick up light shinning down boiler sight glass, say when boilers up to temperature, photocell picks up some light, the panel thinks there's a flame like a big lump of carbon on d head burning, and locks panel out.
You'll go out on call, Murphy's law it'll be a dull day and there'll b no apparent fault.
If the plant room door is open on a sunny day, sun shining in can make d burner go to lock out.
Photocell can pick up light shinning down boiler sight glass, say when boilers up to temperature, photocell picks up some light, the panel thinks there's a flame like a big lump of carbon on d head burning, and locks panel out.
You'll go out on call, Murphy's law it'll be a dull day and there'll b no apparent fault.
D
Dotty
Vaillant ecoTecs
If you have random unrelated intermittent faults.
Get a cuppa turn it on heating and watch the display. If the boiler flow temperature jumps around from say 55 to 62 and back in the blink of an eye the PCB needs replacing. It can take 5-10 min to start doing this.
Video on next post.
If you have random unrelated intermittent faults.
Get a cuppa turn it on heating and watch the display. If the boiler flow temperature jumps around from say 55 to 62 and back in the blink of an eye the PCB needs replacing. It can take 5-10 min to start doing this.
Video on next post.
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Vaillant EcoTec Plus - if you fit an external expansion vessel make sure it goes on the return! Had a nightmare with one today, kept getting F75 (no pressure increase when pump spins). Eventually found out it was because I'd fitted the expansion vessel on the return - NEVER AGAIN!!
You wanna read that again!
You're advising for a expansion vessel to be fitted on the return yet you had a nightmare when you fitted it on the return!!
You're advising for a expansion vessel to be fitted on the return yet you had a nightmare when you fitted it on the return!!
M
mikeyc
Turned off and drained down an arriston microgenus to find on re filling and powering on the fan wouldn't spin.
Checked voltage to fan = nada, assumed PCB. Was about to go buy PCB before remembering the main circuit flow switch needs to make before your get fan/ignition.
Air in diaphragm - bleed pump = save your self a fortune and embarrassment.
Checked voltage to fan = nada, assumed PCB. Was about to go buy PCB before remembering the main circuit flow switch needs to make before your get fan/ignition.
Air in diaphragm - bleed pump = save your self a fortune and embarrassment.
M
mikeyc
Another one iv had a few of recently is a blocked condensate rubber tube on the greenstars (cubed trap not the bottle) - give it a squeeze and work it out. And of course wash it through with some water
G
gileros
Ariston Microgenus He fault code e34, MI's say APS not making. If the boiler fires up when you take the inner case off then you need to remove the restrictor ring in the flue. Spoke to a Ariston engineer on a product training day who told me to undo the flue elbow and remove the restrictor ring as it's not supposed to be there and it actually worked.
Greenstar Jnr etc with cylinder HEX.
Firing then shutting down going to lock out, crazy CO readings and wouldn't react to gas valve being set up, rubber hose from gas valve had perished and split. Blocked condensate also common if these haven't been serviced, you can usually hear this though, had one recently where the grit that gathers in WB's had totally choked the limestones in the soakaway causing an air lock. Took a bit of sussing out as the condensate wasn't backing up....
Firing then shutting down going to lock out, crazy CO readings and wouldn't react to gas valve being set up, rubber hose from gas valve had perished and split. Blocked condensate also common if these haven't been serviced, you can usually hear this though, had one recently where the grit that gathers in WB's had totally choked the limestones in the soakaway causing an air lock. Took a bit of sussing out as the condensate wasn't backing up....
Captain.rick
Gas Engineer
would be good if we could have a section like this that we could search a particular boiler as this list grows it could take a while to search through
N
neily01
Remeha advanta plus
When using hot water pretty much straight away even before pre purge the boiler locks out with a e13 fault, hex thermal fuse fault.
If you reset and run heating all will be ok as soon as hw demand e13 fault. I linked out thermal fuse during hw demend and still e13 fault.i checked thermal fuse for continuity all ok, its a known but unusual pcb fault. In my case i removed hw flow sensor so would not activate hw mode and it ran happily for the heating until i returned with pcb 30mins swithed and set up.
When using hot water pretty much straight away even before pre purge the boiler locks out with a e13 fault, hex thermal fuse fault.
If you reset and run heating all will be ok as soon as hw demand e13 fault. I linked out thermal fuse during hw demend and still e13 fault.i checked thermal fuse for continuity all ok, its a known but unusual pcb fault. In my case i removed hw flow sensor so would not activate hw mode and it ran happily for the heating until i returned with pcb 30mins swithed and set up.
Ariston Microgenus 24 HE MFFI. Hot water temperature too low. Remove the flue restrictor from under the flue elbow.
B
Burger
Had a Vaillant ecotec pro 28 yesterday - F75. Checked sensor, was ok but changed anyway, renewed pump head, still no pressure rise detected and still F75. Ended up being a PCB fault 😵
Can be electronic side of sensor, had a few (including new ones) where sensor reads decent pressure, but gauge inside boiler reads zero 😱
Can be electronic side of sensor, had a few (including new ones) where sensor reads decent pressure, but gauge inside boiler reads zero 😱
Attended a 24ri a few days ago with just the blue light flashing - would not fire & was working up until yesterday.
Worcester fault sheet suggested:
Gas pressure
Co2 levels
Electrodes
Gas coils
Possibly pcb.
In other words could be anything.
I picked up a set of electrodes & a gasket.
On removal the rectification electrode was a bit short but the electrodes were sparking.
Removed the fan & found part of the rubber flap in the air-gas mixing chamber was missing. The other bit had passed through the fan & was sitting in the bottom of the burner.
Another merchant visit new flap installed & boiler rebuilt.
Still exactly the same fault.
Both coils tested & good resistance 35v being sent by board so all ok there. Gas pressure 23mb but noticeably no drop when the boiler was trying to fire. I would have expected a good 1 or 2 mb drop when trying to fire so deduced that the gas valve had also failed. Fortunately had a spare in the van which does several of the Worcester range.
Factory reset as a start point & apart from 440ppm it fired.
All adjusted to book Co2 settings.
In all about 5 hours including merchant visit.
So the fault sheet was more or less correct in that all those things were wrong with the exception of the pcb.
A bit unusual to get 3 parts fail at once, fortunately the customer was perched on my shoulder & could see each faulty part as they were uncovered.
Regards
Arthur
Worcester fault sheet suggested:
Gas pressure
Co2 levels
Electrodes
Gas coils
Possibly pcb.
In other words could be anything.
I picked up a set of electrodes & a gasket.
On removal the rectification electrode was a bit short but the electrodes were sparking.
Removed the fan & found part of the rubber flap in the air-gas mixing chamber was missing. The other bit had passed through the fan & was sitting in the bottom of the burner.
Another merchant visit new flap installed & boiler rebuilt.
Still exactly the same fault.
Both coils tested & good resistance 35v being sent by board so all ok there. Gas pressure 23mb but noticeably no drop when the boiler was trying to fire. I would have expected a good 1 or 2 mb drop when trying to fire so deduced that the gas valve had also failed. Fortunately had a spare in the van which does several of the Worcester range.
Factory reset as a start point & apart from 440ppm it fired.
All adjusted to book Co2 settings.
In all about 5 hours including merchant visit.
So the fault sheet was more or less correct in that all those things were wrong with the exception of the pcb.
A bit unusual to get 3 parts fail at once, fortunately the customer was perched on my shoulder & could see each faulty part as they were uncovered.
Regards
Arthur
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