Worcester 28i junior no hot water, sometimes

[wussel]

I have a Worcester Bosch 28i Junior. Central heating works fine. Hot water doesn't work occasionally. The red flashes light quickly when this happens, holding it down resets everything and usually starts the hot water, sometimes it takes a couple of goes.

This hasn't been too much of a problem since moving into the house 2 years ago, it only happens once every couple of months, and then tends to only happen in chilly weather ie less than +10c.

Yesterday it happened everytime we demanded hot water, so appears to of suddenly got worse, but was fine for my wash this morning.

I want to get this problem sorted before it compleatly breaks forever. I havn't gone through the fault finding in the service instructions yet, becasue it is so intermittant.

Any thoughts?

 

[desrob]

get a qualified plumber/heating engineer to look at it.

 

[rm1]

are you gas safe registered,why come on for advice without carrying out the basic checks when the appliance goes faulty if its your property

 

[Jamino92]

I could be completely wrong in saying this but if your heating is working then the boiler is obv igniting. If boiler isn't igniting when you turn the hot tap on then it maybe that your Flow switch is faulty. To be sure though I'd get someone out to have a proper look at it.

 

[Jamino92]

Just had another little think now, it could be that your divertor valve is stuck/ sticking.

 

[wussel]

I'm reluctant to call out a heating engineer, if it is going to be something easy and cheap to replace like the DHW sensor.

Following the basic fault finding guide in the manual won't help diagnose the correct item failing, it is too intermittant, that the fault finding guide will always suggest it is the pcb or harness.

Is it possible it is just something simple like the wind blowing the wrong way into the flue?

 

[SimonJohns]

I'm reluctant to call out a heating engineer, if it is going to be something easy and cheap to replace like the DHW sensor.

Following the basic fault finding guide in the manual won't help diagnose the correct item failing, it is too intermittant, that the fault finding guide will always suggest it is the pcb or harness.

Is it possible it is just something simple like the wind blowing the wrong way into the flue?

Your dangerous

Get an engineer in

 

[wussel]

I'm sorry, I know my limits, I won't attempt anything dangerous. If needed I will always get help and am willing to pay for it.

I am a licensed aircraft engineer, I know how to fault find complicated systems. Changing a sensor is well within my capability. I only wanted to know peoples thoughts what the likely failed compent might be.

 

[SimonJohns]

Do you know how to perform a gas tightness test and a full combustion analysis with the knowledge of most technical bulletins that may apply to the safe operation of the boiler?

 

[wussel]

Like I said, I know my limits, I only asked for advice. From that advice i'd weigh up the job and then get a technician in if it was above my ability.

At least after using this forum i'd hope to have a heads up as to what the actual failure could be, before they change the PCB and all the other non essiental work after being called back half a dozen times to fix the same fault.

At the moment I do not need to know how a gas tightness test is performed exactly. I will never need to know how to do it. I know my limits, you don't