Plumbing Schematic

[andy]

Hi all

 

So things move glacially along here.  Perhaps we'll actually get the ground works started in July but I am not holding my breath as it was (theoretically) supposed to have been December...

 

But whilst we wait, I've been busying myself with plumbing design, trying to work out what the best option is here and I've come up with the attached so far:

 

 

I'm quite sure there are numerous things I need to add/remove/correct in it but what I wanted to try and get to was a design that made sense, so I can get a plumber to get me up to AHSP/hot and cold manifold level, so I can do the Hep2O runs to each room as needed.

 

I like @JSHarris idea of having a continually circulating UFH pump but I'm going to have two pumps and linked to this I am also not sure whether to do a single zone per manifold or split them up into zones per room.  I think continuous circulation is only sensible if you have a single zone.

 

Again, conscious of following the KISS principal and how far I seem to be deviating from it on this design so far...!

 

My plans for the control system is Loxone but I will need to ensure I have the correct inputs into that e.g. use Loxone switches per room as thermostats to request heating (again makes more sense to have multiple zones then).  Or do I just nominate two Loxone switches, one for each manifold and get that to run as required?

 

The house isn't up to passive levels mainly due to the stretched out shape of it but it isn't too far off with 300mm EPS100 on top of beam and block floor and 300mm warmcell filled timber frame walls, 350mm warmcell filled roof.

 

Anyone have any thoughts/corrections on the above?

 

I am also happy to upload the Visio that sits behind this if that is of use to anyone?

[ProDave]

First comment, your UVC expansion vessel wants to be connected directly to it, not the other side of a service valve

 

I only have one circulating pump for the whole ASHP in the flow from the ASHP, that serves HW and heating. the UFH manifolds have their own circulation pumps.

 

Automatic bypass between ASHP flow and return as far away as you can get it from the ASHP before any electrical controlled valves.

[andy]

Thanks @ProDave, I've update the expansion vessel location.

 

I didn't know if a separate pump was required in addition to the manifold pumps but I've added one on the return.

 

I did have an automatic bypass between the ASHP flow and return but wasn't 100% sure if it was needed and where it needs to go.  At present I've got 3 valves - one for each UFH manifold and one for DHW, I could have a single one that diverted between DHW and UFH I guess but that would serve both manifolds?

[ProDave]

3 hours ago, andy said:

Thanks @ProDave, I've update the expansion vessel location.

 

I didn't know if a separate pump was required in addition to the manifold pumps but I've added one on the return.

 

I did have an automatic bypass between the ASHP flow and return but wasn't 100% sure if it was needed and where it needs to go.  At present I've got 3 valves - one for each UFH manifold and one for DHW, I could have a single one that diverted between DHW and UFH I guess but that would serve both manifolds?

3 port valves imho are the work of the devil. Stick to 2 port valves.

 

My own HP has a "feature" that it turns the pumps on all by itself if it senses the water in the HP is getting near freezing. If I didn't have a bypass, then all the flow valves would be shut and it would have nowhere to circulate.  Place the bypass at whatever point it furthest from the HP.

[willbish]

If your house is stretched out and groundfloor only, maybe you would benefit from a hot return circuit to minimise wait times for hot water.

 

Could be well controlled by Loxone eg only running the hot return circuit pump when activity in the house is detected.

[puntloos]

9 hours ago, andy said:

Hi all

 

So things move glacially along here.  Perhaps we'll actually get the ground works started in July but I am not holding my breath as it was (theoretically) supposed to have been December...

 

But whilst we wait, I've been busying myself with plumbing design, trying to work out what the best option is here and I've come up with the attached so far:

 

 

I'm quite sure there are numerous things I need to add/remove/correct in it but what I wanted to try and get to was a design that made sense, so I can get a plumber to get me up to AHSP/hot and cold manifold level, so I can do the Hep2O runs to each room as needed.

 

I like @JSHarris idea of having a continually circulating UFH pump but I'm going to have two pumps and linked to this I am also not sure whether to do a single zone per manifold or split them up into zones per room.  I think continuous circulation is only sensible if you have a single zone.

 

Again, conscious of following the KISS principal and how far I seem to be deviating from it on this design so far...!

 

My plans for the control system is Loxone but I will need to ensure I have the correct inputs into that e.g. use Loxone switches per room as thermostats to request heating (again makes more sense to have multiple zones then).  Or do I just nominate two Loxone switches, one for each manifold and get that to run as required?

 

The house isn't up to passive levels mainly due to the stretched out shape of it but it isn't too far off with 300mm EPS100 on top of beam and block floor and 300mm warmcell filled timber frame walls, 350mm warmcell filled roof.

 

Anyone have any thoughts/corrections on the above?

 

I am also happy to upload the Visio that sits behind this if that is of use to anyone?

 

Wildly in general it would be great to have such a set of resources once they are a little 'community approved'

 

[andy]

I'm happy to upload the Visio but I'd like to iron out any obvious flaws that exist first.

 

@Nickfromwales any thoughts if you have 5 mins?

[Nickfromwales]

On 13/05/2019 at 11:24, andy said:

I'm happy to upload the Visio but I'd like to iron out any obvious flaws that exist first.

 

@Nickfromwales any thoughts if you have 5 mins?

Apologies, but only seeing this now.

I'll have a look when i get 5 mins, but at first glance it seems a little pointless going for such a small accumulator. That will have <125L of useful volume and is dependant on the incoming cold mains value. Have you done a reading for static pressure and dynamic flow rate yet? To decide on an accumulator volume these need to be known, and your max cold mains dependency understood.  

[andy]

Hi @Nickfromwales no problem at all!!

 

Pressure was tested but only once so far and it’s 5.5 bar and circa 20l/min flow rate.

[LA3222]

@andy did you ever get around to producing an updated version of your schematic from what you originally posted here? If you did I would be interested in seeing it if at all possible?

 

Ta

[andy]

On 30/09/2020 at 11:37, LA3222 said:

@andy did you ever get around to producing an updated version of your schematic from what you originally posted here? If you did I would be interested in seeing it if at all possible?

 

Ta

 

I did and whilst this doesn't represent the final version as I made some changes (left of the thermostatic mixing vales on hot manifolds and just did a single one), here's the JPG but I can't upload the Visio here.

 

I also didn't go for an accumulator and have a low loss header in the loft.

 

Edited October 23, 2020 by andy

[LA3222]

53 minutes ago, andy said:

 

I did and whilst this doesn't represent the final version as I made some changes (left of the thermostatic mixing vales on hot manifolds and just did a single one), here's the JPG but I can't upload the Visio here.

 

I also didn't go for an accumulator and have a low loss header in the loft.

 

Thanks for this, I will have a good look later and hopefully develope my own plan further using this.

[Adam2]

Thanks so much, incredibly helpful. Who knew there was so much going on with water ? If there is a way to post the visio - even renamed as a jpg maybe then that would be great as could adapt.

 

[andy]

On 24/10/2020 at 20:24, Adam2 said:

Thanks so much, incredibly helpful. Who knew there was so much going on with water ? If there is a way to post the visio - even renamed as a jpg maybe then that would be great as could adapt.

 

 

Hi

 

Download from Dropbox here.

 

Andy

[Adam2]

On 27/10/2020 at 06:52, andy said:

 

Hi

 

Download from Dropbox here.

 

Andy

@andy thanks sooooo much for this, only just came back and saw it ? Will save me a load of time

[andy]

1 hour ago, Adam2 said:

@andy thanks sooooo much for this, only just came back and saw it ? Will save me a load of time

No problem @Adam2 I was AWOL for a long time due to being utterly buired in the build (luckily not literally!).

 

What I'd say worked nicely is the the continuous Hep2O runs to each appliance (apart from my en suite basin - I really couldn't be arsed to run another pipe just for the loo right next to it).  The manifolds were made up in 22mm copper.  As I mentioned, I didn't bother with the thermostatic mixing valves on the manifolder either, just not needed when you're talking about DHW only up to 50C anyway.  I have used more Armourflex lagging then makes any financial sense too!

 

UVC discharge dumps into Hotun high flow tunish which then uses PP to eventually dump into an internal stack - much better than any nasty pipes going outside.

 

I took the outside taps off after the PRV, in hindsight maybe they should have gone before but hell I am not loosing sleep on that one

 

I didn't bother with any raditor feeds - these are now going to be electric ones controlled by Loxone (as is the comfort electric UFH in the bathrooms).  I also didn't bother with electronic thermal shutoffs.

 

Also I should've allowed for really good sized service voids to run all this stuff more comfortably, it was tight in places and bloody hard work due to that.

 

The biggest pain I had was trying to work with the layout the house has ended up being - I think my ASHP is about 15m from the loft as the goddam 28mm Hep2O wiggles... next house I have already got a list of things to do differently and I am so far from done on this one...!

[PeterW]

1 hour ago, andy said:

As I mentioned, I didn't bother with the thermostatic mixing valves on the manifolder either, just not needed when you're talking about DHW only up to 50C anyway. 

Part G of the Building Regulations require you to limit the temperature of any hot water at a bath to 48°C so you will need to fit a thermostatic mixer or use a TMV at any bath outlet. 
 

This is one I have seen checked by a BCO too ..! 

[andy]

1 hour ago, PeterW said:

Part G of the Building Regulations require you to limit the temperature of any hot water at a bath to 48°C so you will need to fit a thermostatic mixer or use a TMV at any bath outlet. 
 

This is one I have seen checked by a BCO too ..! 

Bath has and showers have Crosswater TMV fitted.

Edited January 8, 2021 by andy