Gravity HW, pumped CH.

[jezza]

Hello. A customer has a gravity HW, pumped CH system, boiler is (I think ) an Ideal Classic. Heating is a one pipe system. There is unwanted circulation in rads when the programmer is calling for HW only, above and closest to the boiler. Access is poor, but the CH flow is very hot, return stone cold. There are no motorised valves. I'm wondering if there could be a faulty boiler thermostat? I have looked for, but cannot find, an anti gravity valve, so I'm assuming there isn't one. Ideally I would like to get it working as it should without upgrading it to a fully pumped system at present.

Any advice please? Many thanks.

 

[solutions]

Does the pump turn on hw only? Is the hot water hot? Is there a cylinder stat?
The forum has rules regarding the exchange of information on repairs on boilers that may only be conducted by a gas safe registered engineer. If you are gsr get your posts up to ten, message a mod with your gsr details and they will likely give you access to the gsr forum where you can post and will get responses that relate to rectifying boiler faults.

 

[Chalked]

Your on the right track with an anti gravity valve. If it hasn't got one, then fit one. unk:

 

[jezza]

Thanks both.

Solutions, in answer to your questions - no, yes and stupidly I didn't check but if I remember rightly it does have a stat. I'm going to go back and check.