cold feed pipe

Hi Iam just replacing my centrel heating boiler but the system in my house is on gravity hot water. I have got to change it over to a fully pumped system. Does anyone know if its ok to leave the cold feed and expansion pipes on the cylinder coil pipes where they are and fit the pump and motorised valves to the return line of the boiler. This would mean the vent pipe was constantly open to the boiler but the cold fill will only have access to the boiler through the cylinder coil and down the flow pipe to the boiler unless the hotwater valve was open. Thanks Roo

Not really. Blank them off and run the indirect coil pressurised.

Better still fit a pressurized tank.

On Fri, 08 Jun 2007 12:35:58 -0700 someone who may be snipped-for-privacy@bryntwrog.fsnet.co.uk wrote this:-

Very much not ideal and worth changing while the boiler disruption is happening. They should really connect to the pipework near the boiler. There are a number of variables though in terms of where pipes connect and where pumps go, without details of your system there is only so much advice that can be given.

A system as you outline may work without problems for decades, but I wouldn't recommend trying.