Worcester Bosch 280 rsf fires up then stops

[charliedurrant]

Hi,

I have used this forum before to fix my washing machine and dishwasher so firstly I wanted to thank the people who set up this very useful web resource.

I have a worcester bosch 280 rsf combi boiler and this morning it has decided to start and then stop on both the CH and the HW. I have recently had to replace a bulk head valve and replace the secondary HW heat exchanger fibre washers due to leaks.

The status for hot water:

1) Turn off boiler at the mains
2) Turn on
3) Open hot water sink tap and boiler fires up and then stops. I have made a video of what happens

http://www.youtube.com/watch?v=OJZb0PJYr30

4) When the boilers stops (gas supply is turned off by the boiler) various clunks and gurgles come from the top of the boiler behind the primary heat exchanger near the fan

The status is for central eharting is:

1) Turn off boiler at the mains
2) Sometimes starts then stops
3) Sometimes I have to press the reset button - starts then stops
4) Sometimes I have to press the reset button - hum comes from the area behind the reset button and the boiler does not start
5) I have made a video of what happens when the boiler is turned on and the CH starts and then stops

http://www.youtube.com/watch?v=qkOT0GSgVa4


General points:
1) I have hoovered out and cleaned the heating area
2) I have recently replaced a bulk head valve (water in) - 3 weeks ago, CH fully drained
3) I have replaced the fibre washers on the HW heat exchanger - 3 weeks ago, CH fully drained
4) Before 2) & 3) we used to run the cold pressure of the CH at 1bar - I subsequently increased this to 1.5bar as per the manual.
4) I have had a lot of mis-diagmosed problems by engineers - noteably replaced heat echangers when nothing was wrong with them (very costly)

Any help is most appreciated....

Charlie

 

[bengasman]

Sounds like a safety device is engaging.
What do you mean by: cleaned the heating area?

 

[charliedurrant]

Ben,

Nothing more than opening up the main gas burning area and hoovering out the area below the gas burner and specifically hoovering the gas burner and the pilot light. Also a bit of light cleaning of the gas burner panels with a cloth.

Charlie

 

[bengasman]

In that case, I'd recommend you get it checked by a RGI.

 

[charliedurrant]

It doesn't sound good then.....I'm prepared to give anything a go as I'm going away for a week and I'm concerned about leaving my wife with 'worcester bosch' engineers who have in the past charged for non faulty things.....

 

[bengasman]

Are you absolutely sure of that? WB are generally considered top in after sales.

 

[charliedurrant]

Ben,

Yes, as sure as:

1) PCB was replaced - I then put the old one back on as I just couldn't beieve it and all worked okay.
2) The HW heat echanger was replaced as I had the 'hot then cold then hot' water and then a year later I got the 'hot then cold then hot' water again. I cleaned out the 'old' heat exchanger with some Fernox for 5 minutes, put the old one back on and it's been fine for 6 years.

The engineer at the time of the heat exchanger replacement said that my boiler was a right off and since it's an old install I'd have to have a great big stainless flue as the boiler venting was accoring to old regulations. I'm sure the regulations were correct but all in I was quoted £2K for something that has been working fine for the last 6 years.

Why was the boiler a right off I asked? The engineer poked some metal which had rusted due to a leak and said -

"look at it?' it's a mess" - At that point I lost faith in him.

I was no doubt unlucky that day but it did put me off. We also had them out to fix a leak - different engineer. The leak was fixed while I was away. I came back to find it leaking again. A different enginner came out and said we should accept the problem as it wasn't a major leak. It was a bulk head valve which I then replaced myself the next day and has not leaked since.

Charlie

 

[bengasman]

...1) PCB was replaced - I then put the old one back on as I just couldn't beieve it and all worked okay.

That is odd.

2) The HW heat echanger was replaced as I had the 'hot then cold then hot' water and then a year later I got the 'hot then cold then hot' water again.

That is normal. The engineer solved the problem he was called out for. What he did not do (nor was he expected to do as it is related to, but not a problem of the boiler ) is clean out the system.
The system had ( and probably still does ) debris in it due to poor install and/or poor maintenance.

The best of way of finding a good RGI, is asking friends, neighbours etc. for recommendations of somebody who did a good job repairing their boiler.

 

[PEDANTICVINDICTIVEMAN]

Are you absolutely sure of that? WB are generally considered top in after sales.

If you call charging £183.00 for 5 minutes with not a spanner out, giving wrong information and then leaving, yes I'm sure, all it was was a dirty plate xchanger,
I think he should have known that, one of the reasons I've stopped using them, poster is right to be wary.

 

[charliedurrant]

It was no doubt down to who I got on those occasions.

There's good a bad in all walks of life and I was probably just unlucky or they were having an off day - and yes the 2 x ~£183 did hurt the wallet. The heat echanger made me think as was the only part at the time that was not covered by the callout (I guess it's an expensive part) - I agree the fault was fixed, but 50p worth of fernox fixed it too (I do understand that part replacement is a more definate option as the chance of fault repeat will be lower)

Does anybody know where a fault diagnosis chart is available? I looked on Worcester's site but just found the user manual.

Charlie

 

[charliedurrant]

found it via a deeper google search

http://www.worcester-bosch.co.uk/in...280-rsf-discontinued-february-1997-literature[/url]

 

[Agile]

Charlie, I am reluctant to give you much information on fixing it yourself because you have been doing gas related work which should be done by an RGI.

You should not have been charged for parts which dont fix the fault.

The Worcester fixed price repairs dont charge more for parts so if he fits a new PCB thats to your advantage.

The secondary HE gets blocked by dirt in your system. If thats not cleaned then it can block again.

Tony

 

[bengasman]

...(I do understand that part replacement is a more definate option as the chance of fault repeat will be lower)

Not true; both have an equal chance of the problem coming back.

 

[charliedurrant]

Tony,

Fair points. I quite understand about not giving advice. I've had most of the parts off before and am reasonably good at this sort of thing (as good as someone who doesn't do it every day can be) so I was just keen to diagnose the issue before I go away for a week and leave my family.

Charlie

 

[charliedurrant]

...(I do understand that part replacement is a more definate option as the chance of fault repeat will be lower)

Not true; both have an equal chance of the problem coming back.

Not trying to sound like a twit but that does contradict your earlier statement's meaning a little. The engineer did fix the problem, but at the same time the customer was overcharged by replacing a part that did not need replacing. It's a moot point and you get what you get on the day.....

Charlie