Central Heating Pump 5m or 6m?

[help]

Hi,

My Central Heating Pump is not working, how do I no which one to fit 5m or 6m head. just moved in and can't afford a plumber, money is tight.

 

[migoplumber]

on the front of the pump is the data plate. you will see 2 numbers seperated by a dash.
15 - 20 or 35/80 something similar. take that number to your merchant and he can take it from there.

stupid question, but have you checked you have power arriving at the pump and no fuses have blown.

if they have not been used for a while, they can seize, unscrewing the chrome slotted bit in the middle of the face, reveals the spindle, put a small screwdriver in the hole give it a spin!

good luck
shaun

 

[help]

Hi

There is no data plate on front of the pump, but it is green if this is any help. looks like been removed.

 

[migoplumber]

how bigs your system, how many rads. what size pipes?

at the end of the day, if your gonna do it yourself, choose a larger pump model.
costs a tiny bit more, but will work less, so last longer.

make sure your new one has variable speeds. normally 3, so you get adjust as needed.

without data plate your fighting for the same model. but your installation will give you a clue.

did you check power, and free spin??

shaun

 

[help]

Did check power, and free spin. no good.

7 radiators, 22mm pipe on both sides of pump, 15mm pipe on radiators.

you say "new one has variable speeds. normally 3, so you get adjust as needed" how do I know if speed is right?

6m is bigger than a 5m so work less, so last longer. So 5m or 6m does it really matter? what would happen?

 

[migoplumber]

pumps are power rated.
they have to be able to pump up a certain height, and give a certain flow rate.

if you install a more powerfull pump than the instalation requires, water will circulate too fast, and you will have a noisy instalation.
over 1.5 metres a second creates noise.
but that is just one of many calculations you have to make. it gets complicated if your after perfection.
installing a larger pump, use it on less power, setting 1, will give you a longer working life.

bit like using a mini to tow a caravan, might manage a 1000 miles, use a jag and it will do 10000

more complicated but same principal.

 

[unguided1]

take a pic of the pump post it on here someone may recognise the little beasty
Regards
Mike

 

[help]

Think I have found the pump
Wickes  – Heating, Plumbing & Fires – Boilers Accessories – Valves and Pumps – Central Heating Pump 5m Head

They do two a 5m and 6m head of around 5.00 differance in price.
and for 5.00 extra it will last longer. but not to sure on this speed thing,Is there a way of working out how fast it should run or if running too fast or too slow.
Are they good or bad. seem cheaper than others i've seen.

 

[Bernie2]

If yours is an open vent system, watch out for pumping over the header cistern if the pump is set to high. It usually shows as an outside overflow. If the water is really hot when it pumps over, the loft may be full of water vapour if its cold weather. Don't worry though, usually its enough just to turn the pump down and check the water is getting around everywhere.🙂