Freeing a boilers heating pump?
Discussion
Last night it was time to put the heating on for the first time, no radiators got hot though 
We had the boiler serviced and the pump replaced when we bought the house in March and all was working fine then, hot water still gets hot now, just no heat to the rads. Am I right in thinking this is the pump seized up?
I took the little flat cap thing off the front and can see into the pump but can't work out a way to turn it. My Dad said he always just did his with a screwdriver but mines not got a flat or cross shape in it, more of a 4 pointed swirly star! Do I need a special tool? Am I doing something wrong/missing something? Access is a real pain as it's located at the side of the boiler and blocked in by the double oven but I can get quite close but not close enough for two hands on it.
It's a grundfos super selectric 15 60 pump if that means anything to anyone.
We had the boiler serviced and the pump replaced when we bought the house in March and all was working fine then, hot water still gets hot now, just no heat to the rads. Am I right in thinking this is the pump seized up?
I took the little flat cap thing off the front and can see into the pump but can't work out a way to turn it. My Dad said he always just did his with a screwdriver but mines not got a flat or cross shape in it, more of a 4 pointed swirly star! Do I need a special tool? Am I doing something wrong/missing something? Access is a real pain as it's located at the side of the boiler and blocked in by the double oven but I can get quite close but not close enough for two hands on it.
It's a grundfos super selectric 15 60 pump if that means anything to anyone.
If the pump was new in May it is unlikely to be seized up. If the pump also serves your hot water system then it can't be!
Possibilities:
- room thermostat not working (if it has a display does it have a battery?)
- room thermostat set too high (after testing earlier work)
- zone valve stuck so pump is pushing against a closed valve
- massive airlock in the system following the earlier work - try bleeding the radiators.
Possibilities:
- room thermostat not working (if it has a display does it have a battery?)
- room thermostat set too high (after testing earlier work)
- zone valve stuck so pump is pushing against a closed valve
- massive airlock in the system following the earlier work - try bleeding the radiators.
Find the 3 way valve. Over the summer it will have been set to Hot water all the time. And it's most likely now stuck there. On the side of it might be a silver lever (metal) which you can use to manually move the valve. try that a few times and see if it solves it.
Vlave probably look a bit like this:
Vlave probably look a bit like this:
Dogwatch said:
If the pump was new in May it is unlikely to be seized up. If the pump also serves your hot water system then it can't be!
Possibilities:
- room thermostat not working (if it has a display does it have a battery?)
- room thermostat set too high (after testing earlier work)
- zone valve stuck so pump is pushing against a closed valve
- massive airlock in the system following the earlier work - try bleeding the radiators.
Thanks for that. I'll check the thermostat (old fashioned, wired, no battery) tonight as it's just struck me that we stripped all the wallpaper round it at the weekend so it could easily have been knocked right down.Possibilities:
- room thermostat not working (if it has a display does it have a battery?)
- room thermostat set too high (after testing earlier work)
- zone valve stuck so pump is pushing against a closed valve
- massive airlock in the system following the earlier work - try bleeding the radiators.
Don't really know about the zone valves but will check again that I turned them all back on after they were last turned off.
Will also try bleeding rads. I don't know if the pump does serve the hot water as it doesn't rattle/buzz/vibrate when the water's on either. We're in a pretty limescaley area though so seizing 'could' happen I guess.
Do you know the pump is not turning? Can you feel a vibration when everything's on and calling for heat? (Timer on, Stat turned up, rad valves open)
Take the cap off the pump and stick something in there (not your finger) gently to see if it's definatley running or not....
If not, you should be able to spin it with whatever you've just stuck in there to test it.....
Also, there's a 3 speed switch on the pump (near to where the cable goes in if you can't see it), if the pump is running, it's probably set to 1.... turn it up to 3....
If things start working and the rads start getting hot... turn it back down to 2.....
Take the cap off the pump and stick something in there (not your finger) gently to see if it's definatley running or not....
If not, you should be able to spin it with whatever you've just stuck in there to test it.....
Also, there's a 3 speed switch on the pump (near to where the cable goes in if you can't see it), if the pump is running, it's probably set to 1.... turn it up to 3....
If things start working and the rads start getting hot... turn it back down to 2.....
Dave^ said:
Do you know the pump is not turning? Can you feel a vibration when everything's on and calling for heat? (Timer on, Stat turned up, rad valves open)
Take the cap off the pump and stick something in there (not your finger) gently to see if it's definatley running or not....
If not, you should be able to spin it with whatever you've just stuck in there to test it.....
Also, there's a 3 speed switch on the pump (near to where the cable goes in if you can't see it), if the pump is running, it's probably set to 1.... turn it up to 3....
If things start working and the rads start getting hot... turn it back down to 2.....
It definitely wasn't spinning last night but that's without having checked the thermostat.Take the cap off the pump and stick something in there (not your finger) gently to see if it's definatley running or not....
If not, you should be able to spin it with whatever you've just stuck in there to test it.....
Also, there's a 3 speed switch on the pump (near to where the cable goes in if you can't see it), if the pump is running, it's probably set to 1.... turn it up to 3....
If things start working and the rads start getting hot... turn it back down to 2.....
I did the speed switch thing and nothing happened. Will check the thermostat then everything again tonight or get my wife to do it when she gets home before I do.
Thanks for all the ideas so far
Make sure boiler not on, then open up front of pump, use 4mm flat blade screwdriver to turn pump anti clockwise, if no problem turning pump then it could be electrics, check fuses if connected/timer etc. via 13 amp plug, then look at diverter.
Check the radiator controls on first radiator nearest to boiler, see if pipe arriving up to radiator is hot, also check other radiators, if header tank check water level there.
Check the radiator controls on first radiator nearest to boiler, see if pipe arriving up to radiator is hot, also check other radiators, if header tank check water level there.
check to see if you are getting 230v to the pump! i wouldn't asume its the pump without working out where the pump is being asked to come on.
what boiler is it? a divertor valve won't stop the pump running it will only send the heat the wrong way so your heating will get hot in hot water as most rest in heating not hot water.
try linking out all external controls ( room stat) and see if that brings it on as the room stat might be shagged.
what boiler is it? a divertor valve won't stop the pump running it will only send the heat the wrong way so your heating will get hot in hot water as most rest in heating not hot water.
try linking out all external controls ( room stat) and see if that brings it on as the room stat might be shagged.
An update on what I tried last night.
Bled rads, no air at all.
Checked that all valves are open, they are.
Tried thermostat. It was still set to max like we had it in the spring (only tend to have heating on for an hour or two at a time). With heating turned on and 'stat at minimum, turning the 'stat up makes the heating trigger but rather than a whir or pumping sound there was just an electric hum similar to a stuck motor. Turn 'stat down and the hum stops. There is no vibration or movement from the pump at all.
I'm still thinking that the pump is jammed but if not it's something electrical.
If I stick a narrow screwdriver into the little narrow hole in the centre of the pump, how far am I aiming to go in? A cm, an inch? Tonight I will have to disconnect the oven and move it completely out of the way so I can have a proper look.
Bled rads, no air at all.
Checked that all valves are open, they are.
Tried thermostat. It was still set to max like we had it in the spring (only tend to have heating on for an hour or two at a time). With heating turned on and 'stat at minimum, turning the 'stat up makes the heating trigger but rather than a whir or pumping sound there was just an electric hum similar to a stuck motor. Turn 'stat down and the hum stops. There is no vibration or movement from the pump at all.
I'm still thinking that the pump is jammed but if not it's something electrical.
If I stick a narrow screwdriver into the little narrow hole in the centre of the pump, how far am I aiming to go in? A cm, an inch? Tonight I will have to disconnect the oven and move it completely out of the way so I can have a proper look.
Does sound like it's stuck....
it wont take much physical force to turn it by hand tho, just unscrew the cap use a screwdriver or anything to just spin the pump both ways, doesn't matter how you do it.... it'll all come apparent when you get the cap off.....
You'll only get a dribble of water, so don't panic there's no need to rush....
it wont take much physical force to turn it by hand tho, just unscrew the cap use a screwdriver or anything to just spin the pump both ways, doesn't matter how you do it.... it'll all come apparent when you get the cap off.....
You'll only get a dribble of water, so don't panic there's no need to rush....
Agent L said:
I did try that last night, no joy.
Fuse?I might add, although I turn the thermostat thingy in the kitchen, the power to the pump in the airing cupboard is wired into a switch, so that has to be on as well, (One of those with a built in FUSE)
Edited by Vipers on Friday 16th October 13:38
Vipers said:
Fuse?
I might add, although I turn the thermostat thingy in the kitchen, the power to the pump in the airing cupboard is wired into a switch, so that has to be on as well, (One of those with a built in FUSE)
Thnaks, haven't checked that no. As the pump is attached to the boiler and the boiler works it hadn't crossed my mind. There is a switch on the wall (with a fuse) for the boiler though so worth checking I suppose.I might add, although I turn the thermostat thingy in the kitchen, the power to the pump in the airing cupboard is wired into a switch, so that has to be on as well, (One of those with a built in FUSE)
Agent L said:
Vipers said:
Fuse?
I might add, although I turn the thermostat thingy in the kitchen, the power to the pump in the airing cupboard is wired into a switch, so that has to be on as well, (One of those with a built in FUSE)
Thnaks, haven't checked that no. As the pump is attached to the boiler and the boiler works it hadn't crossed my mind. There is a switch on the wall (with a fuse) for the boiler though so worth checking I suppose.I might add, although I turn the thermostat thingy in the kitchen, the power to the pump in the airing cupboard is wired into a switch, so that has to be on as well, (One of those with a built in FUSE)
If it's internal, that fused spur will be the power to the whole boiler (probably).
The boiler is an old floorstanding thing. If you imagine the whole thing as a box that has a square floorplan then the pump sits at the back left corner, within the floorplan but not behind a casing.
I spoke to the plumber that fitted it today, he said I probably just need to stick a small screwdriver in further and then I should be able to free it.
I spoke to the plumber that fitted it today, he said I probably just need to stick a small screwdriver in further and then I should be able to free it.
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