Hi, I'm new to this forum so I hope I've posted this in the right place. I installed a Grundfos UPS2 15-50/60 (part number 98334549) circulating pump into my oil fired central heating system 4 years ago. Recently on the boiler firing up the pump has not started, there is an intermittent ticking sound as though the pump is trying to start but can't. After about 10 to 15 minutes the pump will start and continues to run until the system turns off. This is currently not causing me any issues, other than worrying that there is something waiting to happen. My thoughts are that it may be the run capacitor not having enough umph to start the motor turning but I'm not sure why the temperature of the pump (as this seems to be a factor) results in the pump then running. Having looked into the top of the control box on top of the pump I cannot readily see the capacitor (on the Grundfos pump I replaced the capacitor was readily visible and easily removed/replaced) and I was wondering if anyone on this forum had any advice on how to replace the run capacitor in this particular model. Any help or advice would be greatly appreciated.