General Home Heating fault isolation

[lewissheridan]

Hi,

I have a Potterton boiler that happily fires up, heats for about 2 minutes and then switches itself off.

When I put the programmer on 'Hot Water', the pump gets very hot - the pipes in and out of it are hot too, so the heated water appears to be in the tank, and presumably pumping.

What I notice is that when I turn on the 'Heating' the pipes to the Radiator do not get hot, and the boiler feels as though the thermostat is switching it off.

My feeling is that water isn't circulating, and possibly the pump is broken, if i place a screw driver on it, and my ear to the head of the screwdriver, i certainly hear rushing water, hard to ascertain whether it's actually pumping. The down pipe out of the boiler gets immensely hot, and i have to turn the boiler up to setting 4 to get it to ignite and heat for 2 mins.

There's a constant filling of water sound in the cupboard with the tank whenever hot water or heating is switched on. And the radiators did before hand make a bit of a funning crackling noise.

I hope someone more informed than me can help assist my fault isolation. Symptoms are as follows:

• Boiler heats for 2 mins only before switching off
  Pump gets very hot, and so do pipes surrounding it
  The actuator that switches between hot water circuit and heating does not appear to be working. I unscrewed it and turned on heating and then water, and it did not move a bit.
  
  
  Help! my landlord is not returning my call, email... even if the actuator is broke, it should be divert to hot water pipes.
  
  Appreciate any advise really.
  
  Thanks in advance,
  
  Lewis

 

[Dan Robinson]

So much info, so little detail..

Boiler?
Valve type?
Tank?

Sounds like a pump/sludge problem from what you have posted so far, but we need more info.

 

[lewissheridan]

So much info, so little detail..

Boiler?
Valve type?
Tank?

Sounds like a pump/sludge problem from what you have posted so far, but we need more info.

Hi Dan,

Thanks for the reply.

Yes, lots of info there, but probably not detailed enough to isolate.

I have removed the actuator/valve changing device that switches the route to hot water and heating, i held my hand over the rad pipes to check hot water was coming through. So I think the fault is with the actuator. Feeling quite proud i've isolated it to that, the boiler is happy ticking away now heating, but heating only in short bursts. I suspect the programmer tells the boiler when it wants more ? i have put the boiler setting to '3' (out of 4). The rads are very slowly heating. I turned the pump down to 2 from 3, then turned it back up to 3, and the pumps seems to be certainly working, whirred up a lot quicker.

So i think i might of solved this, consider 3 hours ago i did not have a scooby about heating systems i'm feeling quite proud.

I still cannot explain why if it was going to hot water, why i didn't get hot water and it would only go for a few minutes. very strange.

Anyway i hope you can weed out some sense from that deluge of info about a random heating system. The Boiler is a Potterton Netaheat 15 - 20, the valve i wouldn't have a clue, same with the tank.

Any ideas on what's gone on here ?

 

[swidders]

There's a constant filling of water sound in the cupboard with the tank whenever hot water or heating is switched on. And the radiators did before hand make a bit of a funning crackling noise.

pumping over? - sludged system?