Power surge near boiler- control unit and boiler now dead?

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Last night I needed some hot water quickly so switched on the immersion heater which is normally switch off. There was a loud bang. The Honeywell control unit which is attached to a fuse next to the immersion heater switch/fuse went blank and the boiler shut down. I tried changing the fuse leading to the control unit and pressed reset but just stays blank. The boiler remains lifeless. I tried turning the thermostat on the boiler on manually and can hear the quiet click but it doesn't fire up. My educated guess is there's been some sort of static build up on the immersion heater. This has caused a surge when I've switched it on. This has fried the control unit and quite possibly fuses/circuitboards on the boiler.

Anyone heard of anything like this happening before? I'm trying to get hold of my gas man but Sunday morning so a bit tricky. Got two cold kids and a wife at home!

Cheers!
 
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"My educated guess is there's been some sort of static build up on the immersion heater. This has caused a surge when I've switched it on."

What school of fantasy did you get your education from ?

Chances are the immersion heater has shortened out or failed to ground and you've lost the supply to the boiler which either comes off the same supply as the immersion (it shouldn't) or its taken out the breaker that feeds both (it shouldn't for the previous reason)

You need an educated sparky not a gas man to sort out the electrical fault
 

DP

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Have to agree with jack on this one

But also have to say some of the connections sparkles make on heating systems leave one wondering if they know what they are doing if there are more wires than brown, blue and earth to a lighting circuit or socket :)
 
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Ok cool cheers for your help. Will the control unit need replacing is is it just not working due to a lack of power? Is the boiler likely to be damaged or is again likely to be a lack of power issue?
 
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Failed passive devices (an immersion is such) cannot put energy into the system so in all probability it is simply a case of lost power that is the problem with your boiler and controller.
 
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You have changed the fuse in the fuse spur yes? With same rating?

Did you check the CU board, on MCB for immersion heater / heating has not tripped, if it has, switch off immersion fuse spur and switch back MCB on.

Don't use immersion heater till you get an electrican to attend.

Daniel.
 
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Yep changed the fuse with the same rating and still dead. Didn't actually occur to me to check the fuse board- trying to phone home to get the Mrs to see if it's tripped. Be a massive result if it wasn't dead! Will keep you posted!
 
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Daniel you my friend are a legend!!! Fuse had flicked downstairs all up and running now. Top top man! Thank you.
 
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Don't forget, you still have an electrical problem with your immersion heater that requires attention.
 
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Yes will get it looked at asap. I presume if I leave it switched off at the fuse it's not in imminent danger ie can wait till my spark is next free?
 
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If the immersion is fed by its own fuse then I'd remove said fuse in case someone, inadvertently, turns it on and stops the boiler again.
 
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It is not a "fuse" you switched on but a Magnetic Circuit Breaker ( MCB ).

They react to an over current.

This may have been caused by a wiring fault at the immersion or the element may have failed to earth and need replacing.

I would always recommend a heating engineer for the repair but I do appreciate that some are not very confident/experienced with electrical faults.

Regardless, I do recommend that you do get it repaired because then you will have backup hot water if the boiler breaks down.

Tony Glazier
 

DP

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Magnetic?????

Surely not Tony!!!!

Miniature circuit breaker MCB ;)

Google.....http://en.m.wikipedia.org/wiki/MCB
 
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From Wikipedia:-


Magnetic circuit breakers

Magnetic circuit breakers use a solenoid (electromagnet) whose pulling force increases with the current. Certain designs utilize electromagnetic forces in addition to those of the solenoid. The circuit breaker contacts are held closed by a latch. As the current in the solenoid increases beyond the rating of the circuit breaker, the solenoid's pull releases the latch, which lets the contacts open by spring action. Some magnetic breakers incorporate a hydraulic time delay feature using a viscous fluid. A spring restrains the core until the current exceeds the breaker rating. During an overload, the speed of the solenoid motion is restricted by the fluid. The delay permits brief current surges beyond normal running current for motor starting, energizing equipment, etc. Short circuit currents provide sufficient solenoid force to release the latch regardless of core position thus bypassing the delay feature. Ambient temperature affects the time delay but does not affect the current rating of a magnetic breaker
 

DP

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While the trip mechanism may be magnetic, could equally be thermal, megnetic- thermal even, the component is known as miniature circuit breaker. ;)
 
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