Do I need flexi tails for my ASHP

[joe90]

I am just getting round to installing my ASHP and involving my local plumber ( who will sign off the UVC). He has his own ASHP and when I mentioned flexi tails told me his was installed with solid pipework and he has no noise or other issues , what is the feeling on this subject?

[ProDave]

I think it depends how the pipe run gets into the house.

 

In my case, the pipes will travel a metre or so along the wall, into the garage, up inside the garage into the plant room above.  I suspect that is a long enough pipe run with enough bends that I won't get any transmitted noise.

 

If on the other hand they came straight in to a habitable room I would use flexi's.

[jack]

I know @JSHarris had issues with noise transference when he used (from memory) short/tight flexis with his installation.

[PeterW]

The vibration of any refrigeration unit causes slight issues with any pipe work unless it’s flexible. I don’t think I’ve seen a single MI that doesn’t say use flexis, even if it’s only an isolation from the unit to the fixed element of a few hundred mm. 

 

BES do large bore flexis up to 1500mm for less than £20 which makes install a doddle so I can’t see why you would use anything else ..?? 

[Jeremy Harris]

1 hour ago, jack said:

I know @JSHarris had issues with noise transference when he used (from memory) short/tight flexis with his installation.

 

 

Yes, I did!

 

I stupidly ignored the manufacturers installation instructions, as it was neater to fit 300mm full bore flexis.  There was  massive amount of noise transmission into the house, so I swapped them out for two 900mm full bore flexis arranged in a U shaped loop, as per the manufacturers instructions, and this completely removed the transmitted noise.  I can't now tell when the ASHP is on unless I either go outside or look at the control panel.

[joe90]

Thanks guys, comprehensive reply’s as always, flexis it is then. ( and they are easier to fit ?)

 

is is this what I need?

 

https://www.bes.co.uk/braided-stainless-steel-flexible-hose-3-4-x-1500mm-8131

Edited March 15, 2018 by joe90

[joe90]

On 15/03/2018 at 20:13, joe90 said:

Thanks guys, comprehensive reply’s as always, flexis it is then. ( and they are easier to fit ?)

 

is is this what I need?

 

https://www.bes.co.uk/braided-stainless-steel-flexible-hose-3-4-x-1500mm-8131

 

Are these the right ones to order?

[Jeremy Harris]

They look OK, perhaps a bit longer than needed, but they will do the job alright.  I insulated mine with the thickest Armaflex insulation I could find, then wrapped that with the flexible reflective stuff, just to prevent damage to it really. 

[Nickfromwales]

Any unit that has motors or fans should have flexis fitted to combat the "transmission of vibration" to rigid or fixed pipework. Deffo go for the flexis. 

[joe90]

I am struggling to find a supplier of the correct hoses for my Kingspan ASHP. the thread measures O/D 1 1/4 “ or 32mm. From my reading on tinternet this is a 1” BSP thread!. Also the original Kingspan manual shows their hoses as having a 90’ end ( like a washing machine hose). Also I would like them insulated if possible. Any heads up on suppliers would be welcome.

[dpmiller]

Ask Kingsspan?

Do you have all the other necessary install bits? If not this pricey option might not me such bad value-

https://www.ebay.co.uk/itm/KINGSPAN-AEROMAX-12KW-AIR-SOURCE-HEAT-PUMP-INSTALLATION-PACK-KHP0030-ONLINE-778/162942848059?hash=item25f0268c3b:g:3ZEAAOSw~e5ZPr8X

 

Bud I think someone opined that 22mm was plenty for loadsa kWs so maybe just reduce that 1 1/4" down to suit a more standard part.

[joe90]

Thanks, yes I saw that but don’t need half the kit and I was not sure if the 12kw model used the same kit!!

[Jeremy Harris]

I just fitted an angled adapter to mine to allow me to use more readily available flexible hoses.  As long as the bore is 19mm or so it should be fine.