Design Help - Plumber not helping

[DeeJunFan]

1 minute ago, PeterW said:

 

So this is mine less the PHE which I don't need.

 

Buffer at 0.5Bar/atmospheric pressure.

 

Use a 3 channel timer - one for DHW, one for buffer and one for circ pump and the stat to control the valve to the buffer.

 

 

 

W-Plan modified to allow change over of the pipe stats needed to control the ASHP temp (47/35)

 

And last one with power/neutral removed for clarity

 

 

 

This looks like something you would see when 007 is walking through a russian nuclear plant.

 

How big have you gone on the buffer tank?

 

And Thanks by the way @PeterW

[PeterW]

Looking at a standard 900x300 copper cylinder. I'm leaving the immersion in as that way it means if the ASHP ever fails I've got a big version of @TerryE Willis heater ..!

[DeeJunFan]

1 minute ago, PeterW said:

Looking at a standard 900x300 copper cylinder. I'm leaving the immersion in as that way it means if the ASHP ever fails I've got a big version of @TerryE Willis heater ..!

 

So 58L in old money

 

Thanks

D

[PeterW]

Meant to add the additional wiring is the link from HW Off to No.2 - this pushes the 3 way into heating mode when the HW is off 

[DeeJunFan]

So another update.

 

Plumber #1 has re-engaged and i sent him on some of the more current details on the thread.  he agrees that simplifying is the way to go.

Sounded a bit funny when i mentioned plate heat exchanger but that could just be me.

 

Should be meeting up with him on Monday so we will see how that goes.

 

Thanks

D

 

 

[Nickfromwales]

1 hour ago, DeeJunFan said:

he agrees that simplifying is the way to go.

I know it's easy for me to say sat here, but the proposal isn't exactly rocket science even with the PHE's and the buffer included. 

Lets see what he can do / offer.

[DeeJunFan]

10 minutes ago, Nickfromwales said:

I know it's easy for me to say sat here, but the proposal isn't exactly rocket science even with the PHE's and the buffer included. 

Lets see what he can do / offer.

 

I'm hoping he is going to be ok. I would prefer to know a lot more about it myself but there you go.

 

I like knowing what the other guy is talking about.  

 

Thanks for all the help!

 

Damian

[Nickfromwales]

Update here when your ready . 

[DeeJunFan]

2 minutes ago, Nickfromwales said:

Update here when your ready . 

 

Will do thanks @Nickfromwales

[DeeJunFan]

So have a quick update

 

Plumber #1 came back with a crazy quote and offered no justification or breakdown of costs. 

 

Plumber #2 2 days later came back with a quote 3-3.5k cheaper depending on cylinder selection.  Had a fully itemised quote and UFH pipe layouts drawn so much more impressed with the initial professionalism.  Also seems to know a good bit more then plumber #1 about ASHP 

 

At any rate he came up with his own design and I wanted to sanity check it to make sure my understanding is sound. 

 

So his plan is I'm sure more the out of the box solution for ASHP. Plumber the heat pump directly into the UFH at lower temp say 32 ish ? Then have it prioritise DHW and deliver that at 47 degrees to a 500l buffer with external plate heat exchangers for delivering DHW.  Quoted for a heliotherm fresh water 500.  Which is an eye watering £2155 

 

I know this design really undermines the maximising of ASHP best COP with the max of 40 degrees but it is simple.

 

I could live with that as using direct electric to lift from say 40 to 47 degrees wouldn't be a major issue especially with the solar PV. 

 

Any how.  I'm wondering what you guys think and if you could advise on a secondary plan. Could I buy a Telford 500L store and add exrlternal plate heat exchangers at a much reduced cost?  What Kw of PHE would I need for DHW delivery?

 

Would that setup work out less than £2155?

 

Also I don't think the heliotherm comes with an immersion so that would have to be added to get the most from the PV. 

 

Any thoughts @Nickfromwales @PeterW @JSHarris 

 

Have attached UFH drawings for the craic

[DeeJunFan]

Bump

 

Any thoughts?  Any idea of required PHE sizes/costs?

 

Thanks

Damian

[PeterW]

Sorry missed this..!

 

so are you having a 500 buffer and a 500 UVC..?? 47c is barely hot enough to get most of the blending valves to operate so you probably want Immersions to take this up to 56c (and 65c once a week) 

 

and that floor plan has lots of pipe - 100mm centres..??

[DeeJunFan]

Hi Peter,

 

Just 1 500L buffer for DHW and ASHP going directly into the UFH.

 

Centers are mostly 150 with a few 200mm.  The sunroom is at 100mm.

 

I have solar PV so will be getting hotter than that during the summer and taking it up a bit higher by direct electric i would think during the winter months.

 

 

[Nickfromwales]

On 24/03/2017 at 13:37, Nickfromwales said:

I'd suggest going for a pair of 30kw versions running in parallel to get a combined pipe size input & output of 22mm ( to match the UVC accordingly ). PHE example only

?

[DeeJunFan]

22 minutes ago, Nickfromwales said:

?

 

Lovely stuff, so the paralell 30Kw PHE would provide enough flow for our DHW?

 

I was thinking they were the ones doing the cold water uplift.  

 

Do you think my plan of pairing a Telford 500L buffer with the pair of PHEs would be a decent replacement for the heliotherm 500L freshwater system?

 

http://www.heliotherm.com/en/heliotherm-fresh-hot-water-system.html

 

Thanks

 

[Nickfromwales]

3 hours ago, DeeJunFan said:

I was thinking they were the ones doing the cold water uplift.  

A PHE is a PHE, so, ahem, put it where you like. . 

The helio unit doesn't look that well suited to a low temp input to me, others may think differently. It's basically a TS with PHE's instead of an integral coil, ( admittedly with the added benefit of the better heat transfer characteristics from the PHE ), but will still start cooling quite quickly. That would need a dual cyl stat arrangement to ensure the HP kicked in nice and early to maintain the set temp accordingly. 

 

3 hours ago, DeeJunFan said:

Just 1 500L buffer for DHW and ASHP going directly into the UFH.

At that stage you'd just fit an UVC . If the buffer is disconnected from space heating then that Helio unit is a way complicated and high maintenance option. 

[Alexphd1]

Came across this in a trade catalogue this morning. Ufh mixer valve 20-50 degrees.

[Ferdinand]

The diagrams on this thread are clearly not complicated enough because I can understand them.

 

Mine is going to look like this.

 

 

I was listening to an item about a Yorkshire Malt Whisky on the radio this week; we'll have a Friar Tuck Whisky from Notts.

 

(Sorry: Friday Feeling).

Edited April 21, 2017 by Ferdinand

[Barney12]

2 hours ago, Alexphd1 said:

Came across this in a trade catalogue this morning. Ufh mixer valve 20-50 degrees.

 

Do you have any more info? Suppler? Part no?

Ta

[Alexphd1]

Antaresint.com . They used to be a pretty strict trade only supplier, they where European based so a lot of continental plumbing stuff ie hot and cold manifolds, heat exchangers etc.  I haven't ordered stuff from them in years but there catalogue came through the door this morning.