Central heating Pump siezed.

[Muzz]

So, after a drain down and re-fill I worked on bleeding the system.

i bled the pump and switched on the heating. the pump appeared to be sticking in that it didn't come on immediatly. Now it seems to be siezed completely?

I can hear it make a light buzzing but it's not turning. you can hear it turn when you turn it with the bleed screw.

it's a BG branded myson mutlihead II, got a sticker inside the connection box that says 2001.

Is there anything a can try to get it going or should I just go straight for a replacement due to the age?

I loaned my multimeter so can't check it's getting power, but i'm pretty sure it is.

Cheers,

 

[PlumbGas]

If it is getting the power and it is seized get a new one

 

[muggles]

Can sometimes be temporarily fixed by giving it a whack with an appropriate instrument, but you're going to need a new one very soon

 

[Muzz]

I guess what I mean is I think it's siezed, but wondered if it could be something else I don't know about?

 

[PlumbGas]

I guess what I mean is I think it's siezed, but wondered if it could be something else I don't know about?

Unlikely, sounds like you just need new pump, you may just be able to change the head if the body is a problem, if not then change body aswell

 

[Muzz]

I see screwfix have two grundfos pumps, 15-50 and 15-60, what's the difference? Grundfos site doesn't seem to explain.

 

[picasso]

could just be the capacitor worn out, try spinning the pump anticlockwise with a small screwdriver if it starts you need a new cap.

 

[Muzz]

ok, going to pick up a 15-50 at lunchtime today decided I would just go for a complete swap just for peace of mind.

do I need a special tool to undo the nuts on the pump?

looks like the diameter of the nut is about 5-6cm, not sure if I have a spanner or pipe grip that will go round that.

 

[kevplumb]

change the valves as well
do the job right

 

[Nige F]

I see screwfix have two grundfos pumps, 15-50 and 15-60, what's the difference? Grundfos site doesn't seem to explain.

More pumping ability from the 60 - ie. for a bigger house

 

[Muzz]

i bought some valves in case i break the current ones getting the pump off, was hoping to not drain down again as i had just added the inhibitor.

saying that, the inhibitor will still be in the towel rad upstairs as the pump hasn't run since then, i could just close that rad off until the pumps swapped out.

 

[Muzz]

so, pump swapped and working, managed to get it off quite easily,

one nut off the pump came loose and the compression nut on the other valve.

Valves were weeping so I just removed the olives and put brand new ones on.

struggling to get all the air out of the system though. Bled all rads, pump, boiler, etc but I get a water rushing sound when the pump starts. I think it's because there is no bleed valve on the HW cylinder circuit.

Going to fit one on the flow to the cylinder. I see compression fittings with bleed valves are well expensive, a conex elbow is 30 quid!

Got a good place to put it by either replacing a compression elbow or re-piping a short section with a compression coupling with valve or solder fitting with valve.