Worcester-Bosch boiler problems

[mr-manxman]

I wonder whether any of you gentlemen (or ladies) would be kind enough to come up with some ideas to help me solve an ongoing boiler problem that four separate engineers have now failed to rectify.

The boiler in question is a Worcester-Bosch Greenstar HE 25 combi supplying heat and hot water to a large two bedroom penthouse apartment. Each radiator is controlled by TRVs, which I regularly adjust to control heat, and there are no room thermostats.

For the first year and a bit I owned the flat (which I bought from new), the central heating gave no trouble. Then the boiler started failing overnight with increasing regularity, showing an error code of “EA” (flame not detected). This required rebooting the system, meaning I would awake in the middle of the night or the early hours, freezing cold. Also, the boiler leaked copiously from inside the casing when the heat output setting was not set to maximum or the E position.

Engineers from Manx Gas, the sole gas provider here in the Isle of Man, concluded that the flue had been incorrectly installed and sealed, leading to condensation running back into the system. However, they had little or no knowledge of Worcester-Bosch boilers, so my managing agents appointed another firm to examine the flue, who reached the same conclusion, as did the original installer.

At this point, Worcester-Bosch themselves became involved, and appointed their service agents in the island to examine the boiler. This engineer reached a different conclusion, stating that the flue installation was perfect and that the problem was resulting from an overflowing condense trap, which he cleaned and emptied. The system worked perfectly for the next few months, and then the fault returned (when it happens during the day, the boiler produces a most terrible groaning sound when attempting to locate the flame, and will sometimes switch off and produce the error command “EA” if not rebooted).

At my most recent service, the Worcester-Bosch service agent speculated that the problem could be due to dirty points within the system, which he cleaned, but the problem persists. I am now in two minds as to whether to pay him for the service, as he has failed to resolve the problem after two visits – what do others think?

And with regard to the ongoing problem, any ideas? To summarise:

• The fault is intermittent, and the boiler can work perfectly for days on end, then have a day or two when it misbehaves constantly.
• The fault tends to occur much more when demand for heat is low (one or two radiators switched on, with the TRV set to a low or medium setting).
• The fault may occur more often when there is a strong wind from a particular direction (I am recording every instance now to test this hypothesis).

Any bright ideas as to how this can be resolved? Is it anything to do with the way I am using the boiler or central heating? And who should be liable for paying to have it remedied? Thanks for all your help!

 

[gas4you]

Condensation should run back through the boiler on a condensing boiler

Has the working pressure at the meter been checked?

Why has the WB service agent charged you for anything? Should all be under warranty

Sounds like a weak mixture to me.

Don't know many WB boilers but there are several checks, fan pressure, co2 % that need to be checked and set to see if it is working properly

 

[mr-manxman]

Why has the WB service agent charged you for anything? Should all be under warranty

Boiler is now out of warranty, as it had a two year guarantee, and I bought the flat in July 2005.

Initial visit from the WB agent in May (when they diagnosed the fault as overflowing condense tray) was paid for by WB. Visit a couple of weeks ago (for annual service and further investigation into the fault) was invoiced to me at £58 + VAT. Still debating whether to pay it, as fault has not been corrected.

 

[cjb1971]

If you have a service with a pre existing fault which remians after,then yes the service should be paid for especially if its an intermittent fault which did not show during the service,ive gone to loads of services to be told by the way it isnt wrking properly b4 i start,a service sometimes rectifys problems depending on what it is but other times the service can be done to the MI and the intermitent fault will still occur.

 

[Agile]

Visit a couple of weeks ago (for annual service and further investigation into the fault) was invoiced to me at £58 + VAT. Still debating whether to pay it, as fault has not been corrected.

For such a reasonable bill I dont understand why you are hesitant to pay it! After all he attended and did the service.

Without detailed knowledge of exactly what the problem was caused by its difficult for me to guess what the real problem is.

From the things you have said it makes me think that the problem is a backup of condensate.

Why dont you get a room thermostat fitted so that it complies with the building regulations and is more economical to run?

Tony

 

[bones001]

From the things you have said it makes me think that the problem is a backup of condensate.

Tony

that is exactly what i thought as i had one with the exact same symptons and the problem was the condensate waste was plumbed into the sink waste as was the waste from a dishwasher and the dishwasher waste had caused a blockage in the last elbow on the condensate pipe causing the combustion chamber to fill up

 

[Agile]

I also went to a Worcester with the condensate joining the side of the WMC stand pipe.

The WMC hose had been pushed down past the condensate tee and the soap residue had blocked the condensate outlet.

So simple BUT a BG engineer and a Worcester engineer had both failed to find it !!!!!

Tony

 

[kirkgas]

a simple way to check if the condense pipe is blocked is to remove the rubber tube from the plastic pipe under the boiler, with the boiler not working, if it is blocked you will get some spillage and the boiler will fire up confirming that the pipe needs further attention to rectify the blockage, which might be a partial blockage so be careful to get it properly cleared or the problem will reoccur, had one once which had been installed for about 8 weeks worked perfectly then stopped, removed pipe under boiler as above etc, traced along pipe about 2.5m to waste connection under sink to find that the end hadn't been cut off the w/machine spigot that had been used the problem had taken so long to appear because the pipe had simply been filling up very slowly until it reached the boiler sump.

 

[kirkgas]

a simple way to check if the condense pipe is blocked is to remove the rubber tube from the plastic pipe under the boiler, with the boiler not working, if it is blocked you will get some spillage and the boiler will fire up confirming that the pipe needs further attention to rectify the blockage, which might be a partial blockage so be careful to get it properly cleared or the problem will reoccur, had one once which had been installed for about 8 weeks worked perfectly then stopped, removed pipe under boiler as above etc, traced along pipe about 2.5m to waste connection under sink to find that the end hadn't been cut off the w/machine spigot that had been used the problem had taken so long to appear because the pipe had simply been filling up very slowly until it reached the boiler sump.