Welcome to the forum. Although you can post in any forum, the USA forum is here in case of local regs or laws

Boiler Breakdown Sticky

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.
 
vaillant eco techs F75 fault is always always the water pressure blocked..
 
Last edited by a moderator:
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.


 
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.
 
Last edited:
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
 
en-fault-finding-guide-tmg-mmi-sz20r1205-page-001.jpgAlways handy to have..
 
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
 
stevetheplumber said:
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
Click to expand...

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 goto a intergas combi compact constantly going to 11 fault code, before checking sensors and harness.....remove and clean flow switch as debris can get on the paddle and make it stick in hot water mode.
 
if you have just removed on a service the burner and fan from a duotec HEA/gold/titanium/heatmax/promax combi and you get e133 error make sure you have fitted the silicone tube back to the manifold venturi and not the spare port
 
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.
 
Last edited:
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.
 
abc_plumb said:
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.
Click to expand...

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
 
And check the diverter head hasn't been hanging off for three years since install(by someone else) and sending heat around rads everytime hot tap turned on. I was checking thermistors when valve head droped off.
 
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.
 

We recommend City Plumbing Supplies, BES, and Plumbing Superstore for all plumbing supplies.

Back
Top