Advice with plumbing please

windmill


Joined: 06/07/2008
Posts: 143

Message Posted:
29/12/2008 17:18

I have a potterton boiler which fires up for 3-4 minutes,then goes out,after about 10 mins,i try again,it fires up again,same old pattern,fan is working,fuse ok,has been serviced,any ideas please,cannot get a plumber out for days,and unlike sunny cyprus.it is brass monkeys here (UK)

Graham


Joined: 20/10/2007
Posts: 397

Message Posted:
29/12/2008 17:34

http://www.howtomendit.com/search.php?keywords=potterton



Graham

Geoff1131


Joined: 12/07/2007
Posts: 276

Message Posted:
29/12/2008 17:37

it could be your pump, if the pump is not getting the heat away from the boiler, the thermostat will shut the boiler down, does the boiler re-ignite after say five mins? if so that points to the pump.

Taz666


Joined: 21/12/2008
Posts: 180

Message Posted:
29/12/2008 17:44

take a look at pressure should be 1 - 2 bar at rest depending on model, if gauge in red top up pressure and turn on again, if pressure ok I'm with Geoff1131



How old is the boiler, wall or back boiler?

windmill


Joined: 06/07/2008
Posts: 143

Message Posted:
29/12/2008 18:14

Graham,

Thanks for that

Geoff,i think you are correct,after looking at the website Graham gave me,i checked my pump,its working,but have noticed the pipe from boiler to pump is a lot hotter then the pipe on the other end of pump,have tried making pump work harder,but still no good.

Taz,at a guess,8 years old,will check pressure gauge.

Am i correct in saying.i will not need to drain system,should be turn off valves at top and bottom of pump.

Its just come to mind that i have had to bleed the rads a lot this year,could that be where the water is not being pumped fast enough

Thanks a lot to you all

windmill


Joined: 06/07/2008
Posts: 143

Message Posted:
29/12/2008 18:19

Taz

wall boiler,will be garden boiler if it dont get its act together.

Taz666


Joined: 21/12/2008
Posts: 180

Message Posted:
29/12/2008 18:29

Hi Windmill

If you have had to bleed rads alot this will have reduced pressure in the boiler, read your manual it will tell you what yiur boilers normal pressure should be and how to top up (normally very easy) No you will not need to drain the system just top up at boiler, then you have done this go round all rads and bleed again then recheck the boiler pressure and top up again if need be.

If you are having to bleed rads often you have a small leak somewhere on the system, check all rad valves etc for leaks, it only has to be very very small leak to loose pressure, a small hole in rad valves etc will draw air into the system and pressure on boiler will drop to the point the boiler will not fire up, the pump may be working fine but pumping air round not hot water

Geoff1131


Joined: 12/07/2007
Posts: 276

Message Posted:
29/12/2008 18:39

Tazz, just reread the post and windmill does not say if the boiler is a pressurised system boiler, it may be open vented.

When changing the pump, turn off the valves on either side of the pump, then open the vent screw on the pump to make sure that the valves are working, remove old pump and replace with new one, if you have trouble getting the pump nuts off you can take the four allen key screws out of the pump and fix the new motor to the original base, not ideal but less costly than doing damage to the pipework.

windmill


Joined: 06/07/2008
Posts: 143

Message Posted:
29/12/2008 18:40

Hello Taz,

Nothing in my manual about topping up,really strange,was working this morning,bled all rads,started at number 7 downwards (correct) lots of air in number 1,then it started to play up

windmill


Joined: 06/07/2008
Posts: 143

Message Posted:
29/12/2008 18:44

Hello geoff,

confused about the vent screw on pump,why dont you pop on to a plane and show me

Taz666


Joined: 21/12/2008
Posts: 180

Message Posted:
29/12/2008 18:45

Its air then mate thats tripping boiler out, open up a bleed nipple on a rad, if low pressure in system you will get nothing I.E tiny bit of air then nothing

Geoff1131


Joined: 12/07/2007
Posts: 276

Message Posted:
29/12/2008 18:47

windmill, have you got a small expansion tank on the system that tops the water level up on the heating side of the boiler? In the attic (probably) you should have a water tank for your domestic hot water and a smaller one that tops the heating up, if the small tank is dry, (sometimes the ball valve just sticks) and no water is allowed into the system, this could be another reason for the boiler cutting out, if the ball vavle is stuck simply knock it down and the system should fill, then you may have to re vent.

Geoff1131


Joined: 12/07/2007
Posts: 276

Message Posted:
29/12/2008 18:52

windmill re message 10 just send me a ticket i can be with you in 24hrs

Taz666


Joined: 21/12/2008
Posts: 180

Message Posted:
29/12/2008 18:53

Windmill, if the system is as Geoff mess 8 states your pump will hopefully have a bleed nipple on top, bleed air and try system again, but dont think its your pump, with the amount of air you are getting from rads its sounds you have a leak somewhere on the system

The-Wicks


Joined: 27/05/2007
Posts: 2279

Message Posted:
29/12/2008 18:55

Windmill- got a good plumber in Bury St Edmunds, surprised there are not any in Hampton Court. Hope you get it sorted & happy new year.

P

Taz666


Joined: 21/12/2008
Posts: 180

Message Posted:
29/12/2008 18:59

Geoff could have a good point there, but if the tank is full and valve working correctly follow pipe work from tank which may lead down to a valve below tank, on some boilers a seperate top up valve was instuled for the expansion tank on the system, turn valve open you will hear rush of water do small amount at a time untll boiler fires up and runs, but get someone out asap where in uk are ya?

windmill


Joined: 06/07/2008
Posts: 143

Message Posted:
29/12/2008 19:00

Have just been to look at the boiler,on top is what i believe to be a air vent,opened it,no water at all coming out.

windmill


Joined: 06/07/2008
Posts: 143

Message Posted:
29/12/2008 19:02

The wicks

RUB IT IN

Have a good 2009

windmill


Joined: 06/07/2008
Posts: 143

Message Posted:
29/12/2008 19:04

Geoff,

Will go into the loft and check level

over & out

Taz666


Joined: 21/12/2008
Posts: 180

Message Posted:
29/12/2008 19:04

what happens when you open a rad bleed nipple?

Geoff1131


Joined: 12/07/2007
Posts: 276

Message Posted:
29/12/2008 19:04

right lets get back to basics, have you got a hot water cylinder ie an airing cupboard with a hot water tank in?

windmill


Joined: 06/07/2008
Posts: 143

Message Posted:
29/12/2008 19:08

Geoff,

Yes,

Geoff1131


Joined: 12/07/2007
Posts: 276

Message Posted:
29/12/2008 19:10

Windmill if you still cant fix the problem drop me an e mail, my address is on my profile and i can maybe talk you through a few things to try.

windmill


Joined: 06/07/2008
Posts: 143

Message Posted:
29/12/2008 19:12

Taz,

have you had my email

Taz666


Joined: 21/12/2008
Posts: 180

Message Posted:
29/12/2008 19:13

outshine@btinternet.com



Where in uk are ya

Graham


Joined: 20/10/2007
Posts: 397

Message Posted:
29/12/2008 19:16

Could be the coil on the solenoid of the gas valve breaking down when it warms up.



Graham

windmill


Joined: 06/07/2008
Posts: 143

Message Posted:
29/12/2008 19:18

Geoff,

Thanks,will try a few tips i have been given,will get back to you

MUSIN M


Joined: 26/06/2008
Posts: 1352

Message Posted:
29/12/2008 19:24

windmill



tell me what potterton it is and what system it is ie conventional or combination or is it condensing ,if you tell me exactly what it does i can tell you what it could be ,oh i forgot to mention i am a heating engineer,,lol.



musin

long live the kktc

trevor


Joined: 02/04/2008
Posts: 244

Message Posted:
29/12/2008 19:28

Check the vent fan is working had a similar problem on a boiler at work. The expansion tank is only for the water to go to when it is hot as it says the water expands when hot. Pressure on a boiler should be around 1bar to a max of 1.5 bar although will probably work at 2 bar. If its not the boiler requiring topping up due to low pressure then you have no leaks. Does any of the rads bang loudly?, if so bleed till a constant run of water, are any of the rads only getting warm at the bottom? if so bleed them. Look for the highest rad in your building (is it a house?) this is usually where the air will collect, bleeding the rads will almost certainly not cure the on/off situation unless it is low pressure, are ther any indication lights on the boiler eg low/high pressure, input gas pressure etc.

MUSIN M


Joined: 26/06/2008
Posts: 1352

Message Posted:
29/12/2008 19:59

windmill

just read all the posts and as i understand it is a combination and is wall hung and it,s likely to be a prima if its around 8 years old ,ok the chances are it,s the air switch that starts the fan ,now there are two tubes which feed into the the switch check that there is no splits in them ,but look very carefully as it can be missed easily,if not then the switch itself could be faulty ,you can change it youself it,s simple and they cost £25 .

the other likely thing it could be from the symtoms you describe is the overheat thermistor ,which is located if it is a prima ,is just above the pump on a 22mm copper ,its a little round plastic the size of a one p and has two connections ,pull out the connections and check for continuity with a multimeter

the cost is about 18 quid ,or just change both items ,cheap enough,i,m pretty confident it,s one of these.

ps the bill is in the post.



musin

musin

Taz666


Joined: 21/12/2008
Posts: 180

Message Posted:
29/12/2008 20:14

yes windmill had your email and replied

windmill


Joined: 06/07/2008
Posts: 143

Message Posted:
29/12/2008 20:48

Musin,

I have sealed up the letter box,i am so poor,the mice have left home.

Will get back on here in the morning (i hope )

Trever,thank you

Will have a gas bill as long as my arm,have got the oven & top burners on.

Tucked my wife up in the shed

Had enough for today,if you read in the morning paper,Frozen Body found,clutching his wallet,it will be me,

Thank you all