I moved into a property in Warwickshire that has a 12-15 years old Potterton Puma e80. We have two showers, one on ground floor and one on the 1st floor. The boiler is on the 2nd floor.
We have been having problems with hot water since we moved in but CH works well. There is low flow in all the showers and taps. There is hot water in the ground floor shower but in the 1st floor shower the behaviour is not consistent. Sometimes we get hot water, sometimes hot water for 1 minute then cold water for 2-3 minutes and again hot water/cold water. Last couple of days we got luke warm water in the 1st floor shower. No problem with hot water through the tap on the 1st floor. Only the shower.
We changed the shower head, but no change. We changed the control board of the boiler, but no change. Called some experts and some even checked the boiler/system. one said it's the temp sensor, another one said all sensors work fine it's electrical problem. One suggested over the phone to descale the system. Any ideas?

Natil, November 2008

Hi, I've got Puma e80 which is acting up. Hot water flow is very low and hot water is only for a minute and then cold and again hot and cold. I noticed that the boiler switches off and then on itself when any hot water tap is still on. It's not possible to set hot water temperature using the knob on it's panel as well. CH works well.
Any ideas?

Marek, December 2008

Thanks for the answer Gas Mc. You say:
'Could be a problem with the shower valve if it shuts the hot water off for a second then the boiler has to go through its ignition sequence again hense the 2-3 mins of cold water'
Could that also be because of scale in the pipes?

Natil, November 2008

The thing is, all the boiler knows is that there is a demand for hot water it doesn`t know where its from. Could be a problem with the shower valve if it shuts the hot water off for a second then the boiler has to go through its ignition sequence again hense the 2-3 mins of cold water

Gas Mc, November 2008