Multipipe Maxima FM 16-port manifold (..and 13, 14, & 15)

[mikeysoft]

A company called Multipipe produce an UFH manifold, released in 2023, that can have more than the usual maximum number of 12 ports - 13 to 16 - and claims "The Maxima FM boasts a larger bore, allowing a higher water volume to flow through the system" (and claim the bore is better designed to allow higher flow, implying it's not just about size). They also state that this allows for higher flow rates compared to other manifolds.

https://www.multipipe.co.uk/product/maxima-fm-manifold-16-port-1-inc-aav-gauge-fill-points/

 

https://www.multipipe.co.uk/multipipe-unveils-uk-manifold-first-maxima/?srsltid=AfmBOor5aihAHcgQ3Op3OufFD_M3dPJ-slVMyytyXAihpYceUEDaVcD_

Does anyone have any experience of one of these Maxima FM manifolds in >12 port form?

Aren't most 'regular' generic manifolds 1" bore anyway? They tend to have 1" inlets?

 

I've emailed them asking for some technical details, but haven't heard back yet.

 

Thanks

Mike

 

 

[JohnMo]

£400+ bonkers.

 

Why do you need that many loops are you building a hotel? Either why would you not just do 2x manifolds in a appropriate places in the house.

[Nickfromwales]

34 minutes ago, JohnMo said:

£400+ bonkers.

 

Why do you need that many loops are you building a hotel? Either why would you not just do 2x manifolds in a appropriate places in the house.

It's not bonkers at all afaic. 12's average £300?

 

It could be a big house, I've done houses where we've have 31 ports of UFH.

 

I agree it may be beneficial to have the property split over 2 manifolds to make sure the max runs are <100m, but until we see plans and floor layouts, we cannot possibly comment.

 

So @mikeysoft, me old china mug, lets have some more info please, and possibly some floor plans, then we can stay up and fight.

 

[mikeysoft]

11 minutes ago, Nickfromwales said:

It's not bonkers at all afaic. 12's average £300?

 

It could be a big house, I've done houses where we've have 31 ports of UFH.

 

I agree it may be beneficial to have the property split over 2 manifolds to make sure the max runs are <100m, but until we see plans and floor layouts, we cannot possibly comment.

 

So @mikeysoft, me old china mug, lets have some more info please, and possibly some floor plans, then we can stay up and fight.

 

 

The price feels a tiny bit high as you have to add on pump set etc., but not outrageously so, and from my Googling it's a fairly unique product.

 

The reason I'm actually interested in this is the claims of higher flow rates compared to other manifolds. Even if I were to use one of these in 'only' 12-port form, that increase in flow rate to potentially use, is interesting, for a small increase in cost over a bog standard manifold.

 

The house is big, and I'm looking at two manifolds for the ground floor: a 10 and 12 port (as I'm doing 100mm centres, and having more circuits where there could be less, for reasons I can expand on another time).

 

The spec of the Maximum FM also claims 120m maximum length circuits, but as I said in my original post, I'm waiting to hear back from Multipipe on detail.

Edited July 21 by mikeysoft

[Nickfromwales]

Just now, mikeysoft said:

 

The price feels a tiny bit high as you have to add on pump set etc., but not outrageously so, and from my Googling it's a fairly unique product.

 

The reason I'm actually interested in this is the claims of higher flow rates compared to other manifolds. Even if I were to use one of these in 'only' 12-port form, that increase in flow rate to potentially use, is interesting, for a small increase in cost over a bog standard manifold.

 

The house is big, and I'm looking at a two manifolds for the ground floor: a 10 and 12 port (as I'm doing 100mm centres, and having more circuits where there could be less, for reasons I can expand on another time).

 

The spec of the Maximum FM also claims 120m maximum length circuits, but as I said in my original post, I'm waiting to hear back from Multipipe on detail.

Thanks for the additional detail.

 

Respectfully, I think they're talking bollocks. I've been installing CH/UFH for decades, and every single manifold I have ever seen has a 1" inlet, this is in absolutely zero way any type of innovation.

 

My issue is, unless you put a monster pump onto this monster manifold, to deal with the uplift in hydraulic resistance, then you're going nowhere fast, literally.

[Nickfromwales]

4 minutes ago, mikeysoft said:

The price feels a tiny bit high as you have to add on pump set etc

Same with any manifold from 2 ports upwards.

[mikeysoft]

1 minute ago, Nickfromwales said:

Thanks for the additional detail.

 

Respectfully, I think they're talking bollocks. I've been installing CH/UFH for decades, and every single manifold I have ever seen has a 1" inlet, this is in absolutely zero way any type of innovation.

 

My issue is, unless you put a monster pump onto this monster manifold, to deal with the uplift in hydraulic resistance, then you're going nowhere fast, literally.

@Nickfromwales this is why I'm reaching out to you lot... it could be BS or marketing hype, agreed.

 

It would be good to get some technial info from Multipipe to back-up their claims. It would seem odd a company would produce a manifold that has 13 to 16 ports where others are capped at 12, if they couldn't get good flow rates out of it, and shout about it.

 

As for a bigger pump - surely possible?

[Nickfromwales]

1 minute ago, mikeysoft said:

@Nickfromwales this is why I'm reaching out to you lot... it could be BS or marketing hype, agreed.

 

It would be good to get some technial info from Multipipe to back-up their claims. It would seem odd a company would produce a manifold that has 13 to 16 ports where others are capped at 12, if they couldn't get good flow rates out of it, and shout about it.

 

As for a bigger pump - surely possible?

It is, but if that means longer runs to satellite loops/zones, it makes zero sense. They should state that the loops, can be 120m, if the pump potential is suitably increased, but then you have to balance it all down and risk the temp of the delivered water to the furthest zone being reduced over distance. I had to put right a design from Nu-heat in a £4m house which had a double-decker manifold doing 17 loops, the one I stated had 31 in total, and getting the heat and flow balanced out was a total PITA; to the point that NH stated that they were only in for supply and fit of the pipe and manifold, and the rest was someone else's problem....ffs.

 

If nobody has a polished scrotum, don't invent a scrotum polisher  

 

FYI, these are the pump sets I use for all my clients projects:

 

https://underfloorparts.co.uk/product/ivar-uni-mix-underfloor-heating-ufh-pump-mixing-kit-underfloor-heating-manifold-control-unimix/

 

 

[JohnMo]

Is this a new build - What's the needs or wishes for 100mm centres

[mikeysoft]

On 22/07/2025 at 08:10, JohnMo said:

Is this a new build - What's the needs or wishes for 100mm centres

 

@JohnMo Retrofit to a 20-year old 'individually built' property. Brick and block cavity wall but only with a 70mm cavity (fibreglass insulation), sat on a 100mm concrete raft foundation with 100mm EPS sat under the concrete, running with an LPG boiler. So not great for heat loss as mdern houses go.

 

Want closer pipe spacings to give more flexibility for how we configure and run the system, and we like a warmer house AND we like carpets in reception rooms, as opposed to non-carpets in other big rooms.

[JohnMo]

36 minutes ago, mikeysoft said:

 

@JohnMo Retrofit to a 20-year old 'individually built' property. Brick and block cavity wall but only with a 70mm cavity (fibreglass insulation), sat on a 100mm concrete raft foundation with 100mm EPS sat under the concrete, running with an LPG boiler. So not great for heat loss as mdern houses go.

 

Want closer pipe spacings to give more flexibility for how we configure and run the system, and we like a warmer house AND we like carpets in reception rooms, as opposed to non-carpets in other big rooms.

So assume you are actually going to make the most of condensing mode for the boiler to get very low flow temperature for the underfloor heating and run a second set point for DHW heating - so no S or Y plan?

[mikeysoft]

5 minutes ago, JohnMo said:

So assume you are actually going to make the most of condensing mode for the boiler to get very low flow temperature for the underfloor heating and run a second set point for DHW heating - so no S or Y plan?

What's a S or Y plan?

 

We can run the boiler (Worcester Bosch Greenstar 8000 Life LPG 30kW) at the lowest temperature that allows condensing and gives a reasonable temp for the hot water tank (with a Legionella cycle in the tank).

[mikeysoft]

51 minutes ago, mikeysoft said:

 

@JohnMo Retrofit to a 20-year old 'individually built' property. Brick and block cavity wall but only with a 70mm cavity (fibreglass insulation), sat on a 100mm concrete raft foundation with 100mm EPS sat under the concrete, running with an LPG boiler. So not great for heat loss as mdern houses go.

 

Want closer pipe spacings to give more flexibility for how we configure and run the system, and we like a warmer house AND we like carpets in reception rooms, as opposed to non-carpets in other big rooms.

I was actually considering if we organise the circuits so that the 'carpeted' floors run on one manifold with the blending temperature set higher, than on the other manifold with non-carpeted rooms so that can be run at a lower temperature. Both manifolds are central in the house and co-located, so very possible.

 

And 17mm pipe + 1.25" manifold in carpeted rooms? (17mm 5-layer pipe is hideously expensive compared to 16mm equivalent.)

[JohnMo]

3 minutes ago, mikeysoft said:

What's a S or Y plan?

Is a normal way plumbers install boilers with hot water cylinder and it's the least efficient, so everything is run at a set flow temperature. They use either two normal closed valve or a mid point valve. 

 

Priority domestic hot water, uses a diverter valve and runs a higher temperature with DHW and with a decent boiler can then run weather compensation for the UFH without mixing valve.

 

Effect of flow temp on efficiency 

[JohnMo]

10 hours ago, mikeysoft said:

I was actually considering if we organise the circuits so that the 'carpeted' floors run on one manifold with the blending temperature set higher, than on the other manifold with non-carpeted rooms so that can be run at a lower temperature. Both manifolds are central in the house and co-located, so very possible.

 

And 17mm pipe + 1.25" manifold in carpeted rooms? (17mm 5-layer pipe is hideously expensive compared to 16mm equivalent.)

Sounds like you are making it up as you go. Get a free trial of Loopcad and design it so each room is balanced correctly before you start.

 

Sorry 100mm centres and 17mm pipe and then running your boiler at 50+, to then mix the flow temperature down to supply UFH makes zero sense.

 

11 hours ago, mikeysoft said:

100mm EPS sat under the concrete

Really isn't suitable for UFH. Your downwards heat losses are going to big.

[marshian]

2 hours ago, JohnMo said:

Sorry 100mm centres and 17mm pipe and then running your boiler at 50+, to then mix the flow temperature down to supply UFH makes zero sense.

 

I don't think @mikeysoft's WB LPG Boiler is capable of the low flow temps for UFH - and probably not able to do DHWP either

[Nickfromwales]

34 minutes ago, marshian said:

 

I don't think @mikeysoft's WB LPG Boiler is capable of the low flow temps for UFH - and probably not able to do DHWP either

Depends on how new it is. The LPG's use the same setup, just different jets iirc, so if a modern version then this should modulate; by how much would be down to the exact age/model, but modern WB modulate down quite low afaik.

[SimonD]

18 hours ago, mikeysoft said:

We can run the boiler (Worcester Bosch Greenstar 8000 Life LPG 30kW) at the lowest temperature that allows condensing and gives a reasonable temp for the hot water tank (with a Legionella cycle in the tank).

 

Get the optional diverter valve assembly installed, if it isn't already and then run priority hot water. You'll probably have to modify your heating & hot water pipework. Then, you need a proper modulating control. The problem is that last I dealt with this with WB, they couldn't provide a modulating control that also did multiple zones (this requires 240v relay control), so you'd be required to have one heating zone throughout the house. One of the reasons I don't touch WB boilers. You can have weather comp with this setup though, which would be a sensible choice.

 

On the good side, it'll modulate down to about 3kW.

[mikeysoft]

9 hours ago, JohnMo said:

Sounds like you are making it up as you go. Get a free trial of Loopcad and design it so each room is balanced correctly before you start.

 

I have already done a LoopCAD design.

 

9 hours ago, JohnMo said:

Sorry 100mm centres and 17mm pipe and then running your boiler at 50+, to then mix the flow temperature down to supply UFH makes zero sense.

 

Explain why? You seem to want to make negative comments rather than constructive suggestions to help people - surely the point of this forum: knowledge sharing and idea discussion?

 

9 hours ago, JohnMo said:

Really isn't suitable for UFH. Your downwards heat losses are going to big.

 

So you are saying most retrofit houses with pretty standard concrete slab floors are not suitable - give me some data/evidence to back-up your claim. I disagree - there are lots of examples online of people retro-fitting effectively in this way.

Edited July 28 by mikeysoft

[mikeysoft]

5 hours ago, Nickfromwales said:

Depends on how new it is. The LPG's use the same setup, just different jets iirc, so if a modern version then this should modulate; by how much would be down to the exact age/model, but modern WB modulate down quite low afaik.

 

It's two years old @Nickfromwales. That was my understanding - the Greenstar range for gas or LPG are mostly the same bar the differences you outline. And yes it can modulate.

Edited July 28 by mikeysoft

[mikeysoft]

1 hour ago, SimonD said:

 

Get the optional diverter valve assembly installed, if it isn't already and then run priority hot water. You'll probably have to modify your heating & hot water pipework. Then, you need a proper modulating control. The problem is that last I dealt with this with WB, they couldn't provide a modulating control that also did multiple zones (this requires 240v relay control), so you'd be required to have one heating zone throughout the house. One of the reasons I don't touch WB boilers. You can have weather comp with this setup though, which would be a sensible choice.

 

On the good side, it'll modulate down to about 3kW.

 

Thanks @SimonD- good suggestion. The pipework is already in place like that; I'll look into the rest.

Edited July 28 by mikeysoft

[marshian]

33 minutes ago, mikeysoft said:

 

It's two years old @Nickfromwales. That was my understanding - the Greenstar range for gas or LPG are mostly the same bar the differences you outline. And yes it can modulate.

I wasn’t questioning the modulation 😉 

 

The boiler will have a min flow temp that it can work at - that temp may well be higher than a UFH system can cope with 

 

my old Glow Worm boiler stated min flow temp was 39 deg C - it wouldn’t run at that temp - lowest practical operating temp was 45

 

current boiler min flow temp is 20 deg - lowest practical operating temp is 25 deg 

 

should be documented in the installation manual

[JohnMo]

1 hour ago, mikeysoft said:

Explain why? You seem to want to make negative comments rather than constructive suggestions to help people - surely the point of this forum: knowledge sharing and idea discussion?

Pretty much don't agree, constructive comments about balanced design via Loopcad, you never explained you had it. 17mm pipe is just a waste of money 16mm is more than adequate.

 

Running at low temperature from boiler, gains quite a bit of efficiency and therefore is cheaper to run. Being able to run without mixers saves a fair amount from costs to purchase and additional pump cost extra to run.

 

1 hour ago, mikeysoft said:

So you are saying most retrofit houses with pretty standard concrete slab floors are not suitable - give me some data/evidence to back-up your claim. I disagree - there are lots of examples online of people retro-fitting effectively in this way

I am saying it makes the heating system more expensive to run than say radiators. Simple maths, in both an UFH system or radiator system your floor has the same U value, but with UFH your floor could be at an average of 30 degs. With radiators it would be at 20 degs. Ground temp is circa 6 degs. So delta for radiator floor temp is 14 degs, and with UFH 24 degs. So getting close to twice heat loss. The worse the U value, the bigger the magnitude of the losses.

 

All the subsequent comments from my initial and follow up ones, have been further amplified by others.

 

If your not interested in my input, I will not bother with any further input. You obviously not interested in practical experience driven feedback.

 

 

Edited July 28 by JohnMo

[mikeysoft]

48 minutes ago, JohnMo said:

If your not interested in my input, I will not bother with any further input. You obviously not interested in practical experience driven feedback.

 

I absolutely want your input on retrofit systems, similar to my situation, that you have designed and installed - so yes, please, tell me what I should design?

 

Your constraint is that I have an 90mm build-up to play with from the top of the concrete slab to the external door thresholds, said slab (raft) is 100mm thick with 100mm EPS insulation under, and an LPG heat source. And we like our reception rooms carpeted and at 21 to 22 degrees in the cold months.

[marshian]

52 minutes ago, JohnMo said:

Running at low temperature from boiler, gains quite a bit of efficiency and therefore is cheaper to run. Being able to run without mixers saves a fair amount from costs to purchase and additional pump cost extra to run.

to expand on ^
 

if your boiler can run low flow temps for CH and flip to higher temps for HW (ie with Weather Compensation and DHWP) then running at fixed flow temps with mixers and additional pumps for UFH make no sense

 

my max flow temp for CH at -2.5 outside is 34 deg C (weather compensated system) return temp is in mid to high 20’s so condensing all the time with a boiler efficiency of 97.5 % (validated because I found out how to calculate it)

 

my max HW reheat temp is 80 deg C - efficiency is probably not much more than 86 % - I don’t care because I run the CH 24/7 on low flow temps at max eff and only heat HW tank for 20 - 30 mins a day. So the efficiency gains on CH cover off the poor eff on HW