problems with a noisy water pump

[poc1978]

I have a nosiy water pump on my central heating system and need advice. my bolier heats the water no problem but it won't heat the rads. they are stone cold. I have bleed the rads and the water pump. Any suggestions? Underneath my pump there is a black box which is where the noise is coming from. It has three settings, 1,2 and three. Could this be the problem?

 

[brumylad]

check to see if the pipes on either side of the pump are hot. If one or both is not then the pump is not working or less likely the pump isolating valves may be closed.

 

[poc1978]

pipes either side are red hot!

 

[kevplumb]

IMPELLER FELL OFF

 

[poc1978]

what is the impeller and how do i sort? is it an easy fix?

 

[AdamW]

The impellor is the "propellor" inside the pump. It is the means by which the electric motor pushes the water through the pump.

 

[AdamW]

This is an impeller:

http://www.koikeeping.com/images/Aqua Turn/aquaba

Never looked inside one myself, but the page I got that off is advertising a modification to the CH pump to work with a fish pond. So, it would seem that removing the impeller housing is not difficult.

 

[breezer]

but the page I got that off is advertising a modification to the CH pump to work with a fish pond. .

that is quite common with koi keepers, but as its a steel pump they rust, so some one has made a plastic impellar and housing, you undo the 4 set screws and the pump "comes in two" enabling you to change to the new plastic version

 

[oilman]

I couldn't get AdamW's link to work, but

http://www.koikeeping.com/images/Aqua Turn/aquab.jpg did.

This is the wider picture, much more fun than central heating.

 

[breezer]

I couldn't get AdamW's link to work,

works for me, oilman have you dial up or broadband?

 

[poc1978]

Thanks very much for the advice. This is a very silly question now but as I am as useless with most diy I have to ask. I will have to turn the water off completly before I remove the pump housing? Also, should alll good plumbing shops stock these impellars?

 

[poc1978]

I have just seen the complete pump for sale for £30.00. How difficult would it be to replace myself. My brother can wire it for me but is it actually difficult to take the whole pump out and attach the new one? How would you replace the pump? Is it simple to disconnect from pipes etc?

 

[ChrisR]

Its simple - turn off the isolating valves each side of the pump, remove pump, fit new one, open valves.
But that does not mean it will be easy. The isolating valves will probably not shut completely, and leak as soo ans you touch them, and then youhave to getthe big nuts undone - can be seized solid.

 

[poc1978]

Could a novice do it? I will have qualified person doing wiring and will try replacement myself.

 

[ChrisR]

ANyone culd do it with enough time and tools. 50% chance of having to drain the system and change the isolating valves - better if the valves have a bit sticking up like a stop cock without a top on it, worse if they're 1/4 turn ball valves.