Cylinder primaries in loft space

[DIYAddict]

I'm connecting a vented indirect hot water cylinder to my central heating system, which is in an airing cupboard on the top (first) floor some way away from the boiler and pump. The pump is also on the top floor just aboce the boiler.

Unfortunately, there is no way to route the cylinder coil pipes under the floorboards - too many water and central heating pipes in the way.

It would be simple to route the pipes up into the loft and down again to the cylinder, but this would make them higher than the f & e tank.

Could I get around this just by increasing the height of the f & e tank? If so, by how much - it's a very small loft. Kind thanks in advance.

 

[LUNAT]

HI

running pipes through the loft will cause problems even if you increase
the height of F&E. there must be a way to run pipes straight down.

 

[DIYAddict]

Hi Lunat

There are some large CH and water pipes in the way. I could have route the coil pipes over and under them but this would presumably create additional air traps.

Also the coil primaries are 28mm, and will be insulated (19mm pipe insulation), so some quite large chunks would have to come out of the joists to accomodate them - though I suppose I could just insulate between joists.

What additional problems would be created by running the coil pipes up through the loft and down? Would it be too hard on the pump? I was intending to add air vents at the high points on both flow and return.

 

[Breesey]

Could you not thread plastic primaries through to the coil? And why do you want them to be 28mm?
Where there's a will there's a way.

And you wont want to be "taking large chunks", or chunks of any size for that matter, out of the joists either!

 

[ChrisR]

I doubt very much you need more than 22mm (maybe even 15) to the cylinder.
Your f&e would need to be at least a metre above the high point.

 

[DIYAddict]

I doubt very much you need more than 22mm (maybe even 15) to the cylinder.
Your f&e would need to be at least a metre above the high point.

28mm because the boiler is 35kW and the cylinder's 15m away. Two baths and two pumped showers. I started a thread in the forum debating whether to use 22 or 28mm for the cylinder:
(//www.diynot.com/forums/viewtopic.php?t=129462&postdays=0&postorder=asc&start=0).

The experts were split down the middle so I went for 28mm to be safe. I ordered all the pipe plus some 19mm thick pipe insulation.

Thanks for the info about the f&e height. The loft is long but short so it would be a struggle to raise it that high - I think I'm going to abandon going through the loft and see if I can route it through the floorboards again. Maybe re-rout a couple of radiators

 

[DIYAddict]

Could you not thread plastic primaries through to the coil? And why do you want them to be 28mm?
Where there's a will there's a way.



We occasionally get rodents so I didn't want to risk plastic primaries.

Where there's a will there's a way.]

I think you're right - it will mean re-routing some radiators and knocking holes through two brick partition walls - but I think I've found a route under the floorboards.

And you wont want to be "taking large chunks", or chunks of any size for that matter, out of the joists either!

Hmm that really is a persuasive argument for plastic pipes