Hot Water Cylinder and Oil Boiler?

[wild nomad]

Hi there,

I need to give an estimate on replacing a hot water cylinder. However, it is connected to an Oil fed boiler and I don't have a qualification to to work on oil boilers. Can I still work on the hot water cylinder connected to it?

Thanks in advance

 

[Dotty]

Hi there,

I need to give an estimate on replacing a hot water cylinder. However, it is connected to an Oil fed boiler and I don't have a qualification to to work on oil boilers. Can I still work on the hot water cylinder connected to it?

Thanks in advance

Yes..

 

[SimonG]

Is the hot water gravity fed?

 

[wild nomad]

Is the hot water gravity fed?

Yes, it's a vented system. The cylinder is fed by a CWSC in the loft, although there is a pump on the flow before two motorised valves (S Plan) so it's a fully pumped indirect S Plan.

Here's the weird thing - whoever installed it originally put a 15mm pipe on the return! However, the flow is 22mm.

 

[Ermintrude]

It still requires u to comply with part G building regs. 15mm return to trim system down. Will step upto 22 on common return .

 

[wild nomad]

It still requires u to comply with part G building regs. 15mm return to trim system down. Will step upto 22 on common return .

But doesn't having a 15mm return going into the cylinder contravene with part G?

Oh and another thing. The bypass between the flow and return doesn't have an auto bypass valve. It just has a gate valve thats on all the time?

 

[Ermintrude]

No not as far as I can recall. Your vent must be 22 but flow and return can be "suitably sized"

 

[Whyme]

The 15mm as erm said was to stop cylinder robbing all the heat if both ch and hw demand at the same time, the gate valve is an old idea and there's 100's of thousands around. you probably will have to stick an auto bypass on to comply.

 

[wild nomad]

Thanks guys.

I know back boilers and gravity systems need 28mm so wasn't sure if the fact that it was an oil boiler changed the goal posts or not. It would seem not.

Thanks for your help!