Central Heating Bypass Pipe?

[James Holland]

Hi all,

I have a system boiler with a Megaflow hot water tank and quite a few radiators (approx. 16). My boiler seems to be pretty conventionally plumbed in except for one small bit of pipe.

I've marked it with a red dotted line on the drawing below:

I don't understand what purpose this serves as surely it allows loads of water to take the simplest path back the the boiler without ever being circulated to the radiators or hot water cylinder.

The red circle is an isolation valve, I assume this is partially closed to 'balance' the hot water tank in a similar way to the radiators?

Anybody able to explain this to me?

Thanks

 

[Dan Robinson]

It keeps the boiler happy and stops TRV's making noise.

 

[simond]

I don't think you've drawn this correctly. If you had the HW wouldn't work properly.

 

[James Holland]

Hi guys, thanks for your replies.

Simond, that's 100% how it is, it seems totally bizarre to me!

Dan_Robinson do you think that having it there is correct then? What stops the water simply circulating in the small loop and never going around the radiators?

 

[MJGas]

Maybe a picture would be better

 

[Dan Robinson]

The red dot is drawn on the wrong side of the tee I would wager.

If not then there should be something else on there..... As said by my esteemed colleagues. A picture is needed.

 

[Agile]

I think it is correctly drawn and could work, but the bypass pipe should either be very small bore like 10 mm or should have some kind of valve on it.

Tony

 

[Terry lambert]

It's not drawn correctly and you would get reverse circulation. A picture as said would help

 

[Agile]

We don't know if its drawn correctly or not at this stage.

There are all sorts of abortions out there!

A picture speaks a thousand words!

Tony

 

[picasso]

The op reckons its drawn correctly and if so then the c/heating return is in the wrong place, maybe there is a check valve in place as there is no mention of rads heating up with just the hot water on.

 

[Agile]

I don't see anything wrong with the CH piping. Nor any reason for any rads to heat with CH off.

Providing of course that the CH return is connected close to the boiler as shown.

Tony

 

[picasso]

Three tee rule mean anything ?

 

[James Holland]

Morning all, sorry for the delay, it's really difficult to take a meaningful photograph as it's a bit of a maze of pipework - easy to trace when you can keep moving your head around, difficult from one angle, and from multiple photographs, every pipe looks the same!

I've attached a photograph and attempted to annotate it for you. The red arrows are where I'm not sure why that length of pipe exists.

To clarify, the radiators do heat up when they should. We do get hot water when we should. However, our heating bills are huge and in the depths of winter everything struggles despite the boiler being well sized. My concern is that a decent proportion of flow is going straight back to the return.

 

[Dan Robinson]

That has been plumbed or altered by a complete 'tard.

 

[Terry lambert]

I think it is correctly drawn and could work, but the bypass pipe should either be very small bore like 10 mm or should have some kind of valve on it.

Tony

You think this is drawn correctly and should work?

It's not drawn correctly and you would get reverse circulation. A picture as said would help

We don't know if its drawn correctly or not at this stage.

There are all sorts of abortions out there!

A picture speaks a thousand words!

Tony