Flow and return in airing cupboard.

[Aaron]

Guys,

After a long lay-off I am looking at getting back into the gas industry. I have tried to attach a drawn pic, but was unable to due to a repeated error.

My question is, if a conventional boiler is fitted within an airing cupboard (above the DHW cylinder - vertical flue) and the F/R pipes had a topside exit, I can simply connect the vent and cold feed to the flow above the boiler before dropping down to the pump, to then feed by-pass valve and so on...?

Also, just to confirm, would a manual air pip also be best placed on the return pipe out of the boiler, as well?

Thanks in advance.

 

[Vee]

Best to check head height and configuration in manufacturers instructions before committing. Are you registered to do this work?

 

[Aaron]

Thanks for the reply, Vee.

I actually completed a full apprenticeship in plumbing and heating and passed my ACS, but that was some ten years ago. I am planning to re-enter the field in a few months, and was just recapping on a few things...

I am not planning to undertake any work. This is more for theory. Basically, an attempt to jog my memory...

I remember completing a few of these back in the day (Baxi solos conventional - some sealed - some open vented), but for the life of me I forgot how I configured the exiting pipework out of the boiler...

 

[fixitflav]

Guys,

After a long lay-off I am looking at getting back into the gas industry. I have tried to attach a drawn pic, but was unable to due to a repeated error.

My question is, if a conventional boiler is fitted within an airing cupboard (above the DHW cylinder - vertical flue) and the F/R pipes had a topside exit, I can simply connect the vent and cold feed to the flow above the boiler before dropping down to the pump, to then feed by-pass valve and so on...?

Also, just to confirm, would a manual air pip also be best placed on the return pipe out of the boiler, as well?

Thanks in advance.

Are thinking of going straight down into the pump, so it's pumping downwards? That's possible but I believe it's not ideal. Perhaps others will comment. Alternatively you could add a U-bend before the pump.
By manual air pip(e) do you mean a manual air release point? That would be useful to aid venting on initial fill and commissioning. You wouldn't want an open vent pipe there.

 

[Aaron]

Thanks for the reply. And yes, going straight down to the pump. I have managed to attach a drawing of what I am trying to write...

 

[Aaron]

The above diagram assumes that the boiler is sited above the HW cylinder in the airing cupboard... And yes, I meant manual air release point 🙂

 

[fixitflav]

The above diagram assumes that the boiler is sited above the HW cylinder in the airing cupboard... And yes, I meant manual air release point 🙂

Just for interest, is pip a term for an air release point? I thought you'd misspelled pipe?

 

[Aaron]

Sorry for the confusion. I was taught the correct terminology in college, but the engineer I shadowed during my apprenticeship always termed it 'air pip', or sometimes even just 'pip'.

 

[fixitflav]

OK thanks

 

[doitmyself]

My question is, if a conventional boiler is fitted within an airing cupboard (above the DHW cylinder - vertical flue) and the F/R pipes had a topside exit, I can simply connect the vent and cold feed to the flow above the boiler before dropping down to the pump, to then feed by-pass valve and so on...?

You need to check that the static head for the boiler and the pump meets the manufacturer's requirements. That's the drop from F/E tank water level to the boiler and pump inlets. If it's not sufficient the F/E tank may need raising (which could have a knock-on effect on the relative positions of F/E tank and cold water tank!).