Pulsacoil 2000 - Unstable hot water

We have a Pulsacoil 2000 - when we turn on the shower (or any hot tap) in the apartment the water goes from warm to hot to cold and back to hot every 10 secs or so. We have made sure the settings are correct and that the header water tank on top is filled up, but the problem has persisted. The green light is on on the front and there is no fault light present. Any ideas? The last engineer we called out just fiddled around a bit with the settings and said it might be the sensor, but the problem has continued and we don't want to pay for another engineer unless they are going to fix it this time!!

Thanks

Paul

Hi Paul,

THis is usually heat sensor failure. A new DHW flow sensor will probably fix it, although similar symptoms can be caused by water scale contamination of the heat exchanger.

Cheers, Mike

poconnor wrote:We have a Pulsacoil 2000 - when we turn on the shower (or any hot tap) in the apartment the water goes from warm to hot to cold and back to hot every 10 secs or so. We have made sure the settings are correct and that the header water tank on top is filled up, but the problem has persisted. The green light is on on the front and there is no fault light present. Any ideas? The last engineer we called out just fiddled around a bit with the settings and said it might be the sensor, but the problem has continued and we don't want to pay for another engineer unless they are going to fix it this time!!

Thanks

Paul

The pump could be faulty, but before you change that, check the thermostats are correct