Has my pump died?

[liam2282]

Hi,

I had a rather sludged up central heating system (detailed below) so ran Fernox F3 superconcentrate (2 tubes) through it for two weeks, towards the end of last week the system was hotter than ever before, all rads hot top and bottom - my wife even asked me to turn the heating off at one point which has never been known!!

My plan was to drain down the system on Sunday and refill, drain down, refill etc until running clear then add 2 tubes of F1 on final refill.. however... on Sat night we heard a loud bang followed by whooshing noises, then boiling in the hot water tank. Needless to say I turned it all off, now every time I turn on, nothing happens, then the whooshing, loud banging in pipes and bubbling in the hot water tank. The pump now does not seem to be on, used to hear it as soon as heating/hot water came on, cannot even feel any vibrations when touching it.. so is it dead and thus causing the water just to boil over?

I did drain the central heating system down until running clear and cleared out the heating tank - bled rads etc, has not made a difference..

My system - Potterton Suprima 60L boilder (new pcb fitted yesterday too - had one spare - dont ask...) seems to be working ok? 3 single panel rads, 5 double panel - immersion hot water cylinder, hot water tank and heating tank, grundfos 15 45 18 pump.

Sorry if I have used incorrect terms etc, I am learing as I go and any help is appreciated!

Thanks

 

[Biguns]

Are you confident with electrics. If so remove plastic cap from pump and with system turned on check that there is 240 volts at pump. If so the pump is dead

 

[liam2282]

ok thanks will do, I was thinking of replacing the pump anyway, if the pump is ok & or replaced but the problem remains, any ideas where I would look next!?

appreciate your help

 

[Biguns]

in the cetre of the pump there is a large silver screw. With a dish under the pump remove this screw and insert a screwdriver. If the pump is working youy will feel it vibrate. If it isnt vibrating and there is power to the pump, the fault lies with the pump. If there is no power to the pump obviously problem lies alsewhere, need to know system

 

[liam2282]

thanks, I have removed this screw and the pump is not running at all. I will find out if power is going to the pump, if so I will replace and see where that gets me.

Thanks for your help.

 

[liam2282]

OK so my pump had died, replaced now and working fine.. however, I am now getting what seems to be an airlock, took quite a while for the boiler to force most of it out to the top of the rads, but I can hear bubbling along the pipes going from the boiler to the pump. The nearest rad to the pump also needs bleeding constantly...

The boiler is in my kitchen, the pipes then go through the celing and horizontal across to the opposite side of the house where the pump and tanks are. The section going across the house is not laid completley horizontal and appear to be raised at the boiler end, would air collect in the raised part of the pipes and not be forced out?

or would turning my new pump down a notch sort it? Sorry I am at work now and just thinking of things to try...

Also someone has told me not to worry about using any inhibitor for now as the heating will be on constant while the days are colder?? is this the correct thing to do??

Thanks again for all your help

 

[Biguns]

It may be pumping over . Turn it down to the lowest setting and see if the raditors get hot.
I am assuming that the system already had inhibitor in it, and the new pump was fitted by closing the valves. If the system was drained down to fit the pump, inhibitor should be added

 

[liam2282]

no the system was drained down. I will add inhibitor, just goes to show not to always listen to advice given on a whim!!

I will turn the pump down and see where this gets me.

Thanks again

 

[Whitespirit66]

When I get an airlock, I turn the pump down to 1, and leave the system running like that for a few days.

Then turn the pump right up, it normally clears any air that is left. Then leave it on 2. Was told this trick by my old college lecturer, so he must know a thing or two.