Minimiser goes bang

[pdpettitt]

I have a minimiser SE80 boiler about 7 years old, It has started to produce a loud bang every now and then. The bang happens when its running and not on ignition. It sounds like there is a biuld up of pressure then its released very loudly. I've looked at the flue and it appears to expel water and sludge at the time of the bang. I going to flush the system with a cleanser to see if that helps as I've been told it could be a blockage in the pump (which is about 3 years old) Any help or ideas would be greatfully received.
Thanks

 

[ChrisR]

It sounds like the main heat exchanger may have corroded through, which will mean a new boiler. Unfortunate choice of boiler - some of them lasted half as long as yours
It's usually all wet inside, but sometimes the water evaporates when the boiler's on.

 

[Fluffster]

Like Chris says it is your heat exchanger full of deposits which leave pockets of cold water, when a section of the water heats up and is trapped it turns to steam which increases in volume then hits the cold water section and implodes causing the bang.

A power flush on the exchanger may help but a new one with a powerflush for the whole system and a good inhibitor is your best course of action bar a new unit.
Pete

 

[Agile]

If the bang throws dirt out of the flue than it sounds like a condensate blockage on the burner side. Common problem when they are not serviced every few months.

Either you need an engineer who is prepared to do the required work on the boiler, and few will, or you could take the plumge and replace it with a more reliable modern design.

Tony

 

[ChrisRoberts]

My farther-in-law works as purchase officer for a big london housing assosiation. When a Minimiser lands on his desk with a problem he signs a new boiler request. not nice design. I went to one that BG had serviced, using a flue gas analiser. It was full of Ali'oxide and blocked solid. Had also leaked down onto the fan then thru the bottom of the boiler and killed the pcb too. Quality.

 

[corgiman]

altertnatively just service it properly

it takes about two hours to ensure that all the air ways in the heat exchanger are clean, a right bugger as you have to get your arm up into the heat exchnager with a small blade (i find that a junior hacksaw balde, blunted of course, works the best) up where the burner came out.

then u have to ensure all of the debris is removed.

It could be the the heat exchanger is leaking, but more than likely thatthe explosive ignition is due to lack of CORRECT servicing

whan was the last time a operative spent two hours servicing it

that said they are a heap of shyte and you are better off rid

 

[Trance Nation]

My farther-in-law works as purchase officer for a big london housing assosiation. When a Minimiser lands on his desk with a problem he signs a new boiler request. not nice design. I went to one that BG had serviced, using a flue gas analiser. It was full of Ali'oxide and blocked solid. Had also leaked down onto the fan then thru the bottom of the boiler and killed the pcb too. Quality.

BG engineers, as any other engineer should do, must clean those boilers out properly as per instructions which clearly state a "proper" strip clean service no later than 2 year max interval. As said earlier basically every few months, certainly every year.

Was this a poorly designed boiler ? Have heard a few horror stories on burst heat ex's only a couple of years after first installs. Surely Ideal have to be held responsible if its a design error.