Another Ideal ICOS Bites the Dust! Please READ!

[arran197]

My supervisor sent me and another engineer to fit a fan he diagnosed to an M series ICOS earlier on. Fitted the new fan and BANG! Blew the board. So I checked with Parts Centre to make sure I had the right fan, which was wrong. The engineer I was working with had one on the van, so we swapped it over and put another board on it. It fired up and then BANG!

Switched it off and it wouldn't fire up again. I'd already checked the continuity between the wires and there wasn't 140v DC at the fan, so I thought the wrong fan had blown the board. So I began looking further and tested continuity between each wire with another. Bingo! Continuity between 2 wires. So the wiring loom is at fault. But why? Oh, here's why!

As you can see, the insulation pad has fallen, causing the downward fire to deflect to the alu combustion chamber, melting it in to a hole and then melting the wiring loom! The alu was actually soft, I could crumble it with my fingers. To look at it, you wouldn't have seen any of this due to it being at the rear, it was only when I took the burner off I found it. I've heard of this happening before, but have never seen it and I have been checking them every time I do something more than topping up the pressure.

The cause is the earth pins, which also act to retain the insulation pads. On the M series and early HE boiler, the pads were squared off, so easily fell in after time.

This is a serious situation, the things could easily melt completely and the copper gas pipe sits behind it. I recommend that EVERY time you work on one of these boilers, you take the fan and burner off and inspect them. Any kind problem, AR them and get the replacement parts (which have now been redesigned).

 

[Billy Bob Bob]

i have been saying this for years,i have seen a few do this,i carry a axe for a reason and i dont believe the bull that the logic is better,once melted twice shy and dont start me off about the transformer that over heats killing most pcb,s

 

[Dannypipe]

Hmmmm. Well this is worrying. Its a bit of a pain in the bum to strip and check this on every single ICOS service....but I guess I will have to. Thanks for the photo and info.

 

[Billy Bob Bob]

Hmmmm. Well this is worrying. Its a bit of a pain in the bum to strip and check this on every single ICOS service....but I guess I will have to. Thanks for the photo and info.

strait forward to do mind nowhere near as hard as a greenstar you need to get a gasket set in though

 

[Dannypipe]

Yeah, and a gasket set is about £30 or somthing ridiculous. Have to remove the fan, all in all a bit of a pain.

 

[TBServices]

Always carry the earth pins on van and check the insulation hasn't fallen in. The improved pins come with an orange sticker to show the following engineers it's been done.

Another big problem with these is they're often fitted on prepay elec/gas meters, so when the gas runs out the board gets fried trying to relight the boiler, and when the electric runs out the pump overrun fails and burns out the internals.

This boilers are just awful.

 

[Billy Bob Bob]

Yeah, and a gasket set is about £30 or something ridiculous. Have to remove the fan, all in all a bit of a pain.

fan does not need to be removed from the burner every time,it will come off as part of it

 

[Dannypipe]

Yeah, but its fiddly getting to the hexagonal screws at the back. Sometimes just easy to whip the fan out.

A bit of a faff for an A rated boiler. Especially in its performing well on the combustion results, and doesn't need stripping. Just a pain is all. I will start doing this from now on. I've a fair few Icos's I look after. Pieces of junk.

 

[Billy Bob Bob]

Yeah, but its fiddly getting to the hexagonal screws at the back. Sometimes just easy to whip the fan out.

A bit of a faff for an A rated boiler. Especially in its performing well on the combustion results, and doesn't need stripping. Just a pain is all. I will start doing this from now on. I've a fair few Icos's I look after. Pieces of junk.

1/4 or 3/8 socket set its a doddle nuts are 8mm

 

[Dannypipe]

I guess, but the gasket sets are a rip off, and it's just a pain that I will now want to check this every single time. Which means services are going to take longer, which means I'll earn less!!

Come across cracked insulation panels, but never ones that have completely fallen into the burner. Ah the Ideal ICOS. They're easily the most common boiler in my area. The developers put them in everywhere.

 

[GrahamM]

BG/SG fitted loads of these and advocate the burner is removed to check panels/earth pins on every service visit because of this.

May I also draw your attention to TB108!

 

[Dannypipe]

You may! Thanks.

 

[Dannypipe]

Just read it, all the ICOS's I work on have the ignition/detection probes in the corner. So they're the modified burner, so this will be less of a problem. Don't think I've come across one yet (pre 2003) which has them in the front like pictured in the TB. I will start checking the insulation boards as a matter of course all the same.

 

[Blake]

I condemned one the other week for exactly the same reason. It had a boom on start up which would poss make you believe mixture was incorrect, then I realised it was slowly melting itself from the inside.

 

[frakaka]

I would advise any one who work on these boiler, should always check these probes. I know they are a bit of a pain to get to but lets not forget that is part of our job to keep people safe.

 

[vern]

We had an icos system boiler do this very fault, it had not been maintained at all, it burnt through the back panel, and expansion vessel flooding the place!!
ideal icos / isar in same league as Ocean ff and Saunier Duval combi's AWFUL!

 

[hedgehog65]

Just replaced an Isar...blew two boards..owner sick of it...

 

[arran197]

Ok, so last week I A.R.'d 6 Icos/Isar and I.D.'d this one. The one had got a snapped/sheared off hex bolt at the back of the burner. The other was seized in position and I snapped it. The insulation pad at the back had started to move, causing the alu to get hot and the bolt to seize.

I came across another with the center bolt seized. I applied some WD40 and worked it backwards and forwards and it came out. Same thing, pad falling down. Plate heat ex was also blocked up. A.R.'d boiler and ordered in the new pads, earth pins and a heat ex.

Do Ideal recommend changing the burner seal after every time it's removed, I thought they only recommended it if it was damaged in any way?

 

[Millsy 82]

I was always told only if it was damaged.

All these boilers should be ripped out they are by far the worst boilers I have ever worked on, Never seen this fault as yet had 1 where the pad had just started moving but it was also leaking from the bottom o ring on the heat exchanger the board was shot and the flame rectification lead was bare so was replaced 2 days later with a nice worcester.

These pins should be checked everytime you work on these boilers even if its only a small job. I cant believe the amount of boilers serviced regularly that have still not had the new pins put in and then they warp out of shape aswell so need replacing aswell.

 

[garythegas]

Done loads of these on local authority contract,best tool for removing the pins is a Bosch 3.6v driver with a right angled attachment fitted and an 8mm socket,sometimes the pins snap off then your in big trouble.All m series boilers require probes replacing,some don't have any in at all as they have dropped through the heat exchanger into the sump.Later boilers require probes checking to see if they are ok,this can be done by removing the front 3pins from the burner and levering the burner up slightly with a screwdriver just enough to see the pins,the ones nearest to you can be checked with a small inspection mirror.

 

[garythegas]

Something I forgot to add in my previous post if you find one of the pins at the back of the burner seizes up when trying to remove it,rather than force it and snap it off,the burner can usually be lifted enough to replace the rear probe without having to fully remove burner,sometimes long nose pliers have to be used

 

[Agile]

I do have to say that even having a maintenance contract does not protect the customer.

A lady I know had one fitted by BG four years ago and then maintained it badly so she switched to Homeserve but they were even worse!

It had been leaking from the return pipe at the bottom and they had just put some silicone into the gap. All that did was to move the leak to the back of the pipe where it was less likely to drip onto the display PCB. I improved the plastic leak diverter above the display PCB and advised her to save up for an Intergas boiler to replace it.

Tony