heatslave combi wont fire.

[doorhand]

I have a worcester heatslave 15/19 oil combi boiler, and it wont fire, just locks out. no central heating or hot water.

The water pressure had completely dropped overnight, i refilled the system and let quite a bit of air out.
but boiler doesnt work anymore...

I switch either c/h or hot water on, and fan comes on, pump comes on (and makes a noise, oil [out] (of pump) pipe shakes about. and system locks out.

i have plenty of oil in tank.

anybody any clues or suggestions? because im freezing.

cheers.

 

[Agile]

Bit late to try to get help?

Better to check the pressure regularly and top up as necessary!

I expect an overheat stat has tripped. Try looking for a rusty red thing somewhere to push.

We charge double time after midnight!

Tony

 

[doorhand]

;Better to check the pressure regularly and top up as necessary!
pressure was fine, it completely dropped to 0 overnight.

;I expect an overheat stat has tripped. Try looking for a rusty red thing ;somewhere to push.
overheat stat button not tripped, although lockout reset button has, will reset but locks out next time it trys to ignite.

cheers.

 

[Paul Barker]

When you let the pressure go so low that a boiler's own safety devices kick in you open a window of opportunity for sludge to clog up the works. Sometimes it is necessary to take a few things off and clean them out after such an episode. Mostly people get away with reseting the boiler or oh stat but not everyone is so lucky. How people get to adulthood who don't understand filling loops I have no idea.

Only a fool lets his combi pressure drop below 1.

Watch it weekly, if it doesn't move watch it monthly, but never leave it longer than that. Always check it cold. Never let it go down to 0 again.

If the boiler is remote and inconvenient to watch the pressure put a guage inside the house.

If you have a leak fix it now.

If pipe is blocked unblock it now.

If you can't do these things get whichever is necessary done.

Never leave a boiler in a fault condition, attend to it imediately, it won't get better on it's own.

If the prv is leting bye fix it now.

If the expansion vessel needs recharging charge it now, if it is ruptured change it now.

Might just be an aav not working and you have an air lock to get rid of of course. otoh aav might be leaking too, get that looked at aswell.

 

[oilman]

When you let the pressure go so low that a boiler's own safety devices kick in you open a window of opportunity for sludge to clog up the works. Sometimes it is necessary to take a few things off and clean them out after such an episode. Mostly people get away with reseting the boiler or oh stat but not everyone is so lucky. How people get to adulthood who don't understand filling loops I have no idea.

This lockout may have nothing to do with the water side.

Only a fool lets his combi pressure drop below 1.

Not so, please research "static pressure".

.......... Always check it cold. Never let it go down to 0 again.

Difficult, this boiler has a 70 or so litre store.

Might just be an aav not working and you have an air lock to get rid of of course. otoh aav might be leaking too, get that looked at aswell.

This boiler is not pressure dependent to work.

There are a number of possibilities, oil pump solenoid, ignition transformer, photocell, and unlikely, the control box.
What make of burner is it and model?
how old is the boiler?
How are you on fixing things generally?

 

[doorhand]

How people get to adulthood who don't understand filling loops I have no idea.

Only a fool lets his combi pressure drop below 1.

Watch it weekly, if it doesn't move watch it monthly, but never leave it longer than that. Always check it cold. Never let it go down to 0 again.

You must be some sort of idiot! what part of "pressure suddenly droppped to 0 overnight" dont you understand?

Never leave a boiler in a fault condition, attend to it imediately, it won't get better on it's own.

Yes, well done Paul!


Water moisture had frozen inside oil suply pipe, and created obstruction, thawed out now, heating working again.

Thanks to everyone else who had something helpful to say.

 

[Agile]

I am still wondering why the "pressure dropped to zero overnight"?

We interpret this to mean the system pressure of water in the radiators and NOT the burner pressure. Perhaps you really meant the burner pressure?

Also I wonder why your system does not have a water seperator in the oil feed but perhaps its not always fitted on a domestic oil burning system.

Tony Glazier

 

[oilman]

Indicates lack of maintenance/servicing of oil supply system. There may be more water in the tank, or more likely, your sight gauge is exposed to rain. Check tank for water or you will have a bacterial slime problem in future.

Pressure drop could indicate lack of adequate expansion space in expansion vessel, this should be checked at service time in accordance with BS7074 part 1.

 

[wilhelm]

to get rid of water you open the sludge valve on steel tank. if its got one, if not pump it out, same with plastic..which has no sludge facility.

as oilman said. zero pressure dont give a lock out. on oil burners.

and heres something to cure insomnia.

 

[oilman]

...........
as oilman said. zero pressure dont give a lock out. on oil burners.
........

Unfortunately, Eurocal combies do have pressure switches, a real pain as if combies are not bad enough already.

 

[Agile]

If combis had not been invented and mass produced to keep the price low we would have had most of the country still using 20 year old boilers.

Combis probably account for 90% of repair work averaged across the whole country. They keep repair engineers ( like me ) occupied!

In my case in London with small one bed flats, 99% of my repairs are combis and I love them!

I only go to about two oil boiler installations each year ( thank goodness ), usually commercial installations where it was judged they would be more economical than gas.

Tony

 

[wilhelm]

cheers oilman, i didnt know that....

when i see a eurocal combi , i shall make sure i go tooled up.

 

[oilman]

............

Combis probably account for 90% of repair work averaged across the whole country. They keep repair engineers ( like me ) occupied!
...........................

Just demonstrates what a total waste of resources you can generate and disguise it as progress.