Help us understand how this UFH system works please!

[Gasmk1]

Sorry Gasmk1, not sure what you're saying? Individual rooms (eg zones) with hot water UFH can be controlled by ambient temp. wall stats. I have them. Did you mean it's not controlling the temperature of the water - agree it is just an on/off control of the water supply, but it does work!

You asked me if I had anything to add my answer was no,

I missed a full stop. I was saying that the stats control the heat no timer but you should be able to change them to programmable room stats. But you need to know if you want to do this as cost is involved.

 

[whatsthenews]

Hi whatsthenews
I know of a UFH center like yours with the timer module fitted. I have been looking around to find the "Continental" Heatmax chrono module, but this product seems to have disappeared and the item badged with other names - the only recent equivalent has the "Watts" name.
This is what the module is like:

https://wattswater.eu/upload/iblock/f50/f50445f836482864b474c6a866499d42.pdf

and just for interest I see there's one currently on eBay:

WFHC PLUG IN TIMER UK 2368 BNIB | eBay

Find many great new & used options and get the best deals for WFHC PLUG IN TIMER UK 2368 BNIB at the best online prices at eBay! Free delivery for many products!

www.ebay.co.uk

Whilst this appears to be 'the right thing' I am not guaranteeing it would just plug in and work! We need someone experienced with fitting/ maintaining these to confirm different branded modules of this type can work together. I think the design is at least 10 years old - the system I've seen was installed in 2007.

It seems the industry has moved towards thermostats having time clocks in them, so different rooms can have different timings, rather than one central clock turning everything on and off (or doing setback) together.

Yes, I've seen that set up too and yes, seems most heating controls these days are a combined affair
I wish we knew about UFH as I'm not sure (considering the thermal store is being heated by electricity whatever we do with the stats) whether we should just leave the stats set on 19 all the time. If I have my head around it, as long as there's hot water in the tank ,apart from the electricity to run the pump, the cost is going to be the same, is it not?

no under floor is controlled by thermostats so my advice is set them to what is comfortable other option is to change the stats to timer stats would need to see what the thermostats are to see if its feasible.

the room stats are Continental Heatmax which have 3 settings.Continental Heatmax NSB dial thermostat
We've got them set on the automatic night setback mode, which is designed to set back the temp by 4c overnight, but ,if I understand correctly, this is only going to happen with the use of a timer on the UFH. (That's making the assumption that the Eco 7 is only controlling when the water tank switches on and has nothing to do with the UFH )
We're turning the room stats down to 17c overnight (still on the automatic night setback mode) and at 0800 the UFH has definitely been on and the flat is warm. To get the stat to call for heat they need to be turned up to about 21c. Slightly puzzled as to why it's so warm.

You asked me if I had anything to add my answer was no,

I missed a full stop. I was saying that the stats control the heat no timer but you should be able to change them to programmable room stats. But you need to know if you want to do this as cost is involved.

That was me who asked if there was anything else you could add.

 

[Basher]

(That's making the assumption that the Eco 7 is only controlling when the water tank switches on and has nothing to do with the UFH )

It's right to assume that the Eco 7 timer is just controlling the immersion heater(s). If the UFH chrono module had been fitted originally, then that could have controlled the immersion (eg boiler), but it wouldn't make sense to do it the other way round. The Eco 7 is only on at night, and only for a maximum period of 7 hours!
I'm not clear the night setback will even be working if the UFH chrono module is not there. When switched to setback mode, does the LED change between orange and green when you rotate the dial, and is the point at which that happens indicating about 4 deg. below ambient?

I guess there is no point in making any changes to the system if it is providing adequate heating. If certain rooms are not required to be heated at certain times, it might be worth putting in a programmer (or changing the thermostats) but the saving in electricity would take a while to pay back the expenditure!

 

[whatsthenews]

It's right to assume that the Eco 7 timer is just controlling the immersion heater(s). If the UFH chrono module had been fitted originally, then that could have controlled the immersion (eg boiler), but it wouldn't make sense to do it the other way round. The Eco 7 is only on at night, and only for a maximum period of 7 hours!
I'm not clear the night setback will even be working if the UFH chrono module is not there. When switched to setback mode, does the LED change between orange and green when you rotate the dial, and is the point at which that happens indicating about 4 deg. below ambient?

I guess there is no point in making any changes to the system if it is providing adequate heating. If certain rooms are not required to be heated at certain times, it might be worth putting in a programmer (or changing the thermostats) but the saving in electricity would take a while to pay back the expenditure!

Thanks Basher.
That's what I thought. Spoken to a couple of residents who say they don't have an Eco 7 meter. Presumably the system was set up to be used with Eco 7, so not sure why it's not. Looking at various Eco 7 tariffs, night time unit rates are around 9p, compared to about 14p for standard tariffs. I have no idea how a meter works, especially when it's remote to the consumer unit.
Also agree that the nightime set back won't work. The only LED colour we seem to get on the stat is red.
On closer inspection of the Eco 7 timer, I can see the red "on" tab and the blue "off" tab in the windows.
Red is at about 0200 and blue around 07.30.
Would I be correct in assuming that the immersion has a thermostat so it'll switch off independent of the timer when the water reaches the set temperature?
I still don't fully understand how the UFH manifold works regarding flow and return.
Is there a loop that circulates just through the UF pipes and the 2 sides of the manifold, with the mixer valve (there's a motorised valve) opening to add hot water from the thermal store ie the HW tank) to keep it at the set temp'? As opposed to a bigger loop where the returning water goes into the HW tank and then flows back out around the whole system? Hope that makes sense!

 

[Basher]

I have no idea how a meter works, especially when it's remote to the consumer unit.

These days one can have a dual tariff smart meter, which feeds the same electricity up the same wires, but just records what you use during the defined night time period on one totaliser, and what you use during the day on another, and keeps tabs on the total. Slight problem is that although the night rate is much cheaper, in many cases the day rate is a bit more expensive. So the savings might not be as great as you would think if you need lots of daytime electricity. The heat store is a great candidate for dual rate, but depends what happens during the day.

You may have already had a look at background material on UFH, eg

Underfloor heating explained

Underfloor heating can seem complicated at first but once you know the basics you will see how beneficial it can be. Use this page to understand the basics

www.johnguest.com

I confess my background is electrics, not plumbing. What I don't understand is that the heat store appears to have only one coil, which takes incoming mains pressure cold water, heats it and feeds it to the taps. Apparently the UFH is connected to the same coil. Surely that means that water from your hot taps could be mixed with that running through the UFH pipes, unless there is some sort of hydraulic separation somewhere. It doesn't seem a very hygenic arrangement. I would be interested to hear others observations.
Sorry to ask again, but are you absolutely sure the UFH stops working if you turn the E7 off completely?
(probably not an experiment to do at this time of the year). The presence of the energy monitor is still bothering me

 

[whatsthenews]

How Underfloor Heating Works | John Guest Speedfit - https://www.johnguest.com/speedfit/underfloor-heating/underfloor-heating-explained/what-is-ufh/I[/URL] confess my background is electrics, not plumbing. What I don't understand is that the heat store appears to have only one coil, which takes incoming mains pressure cold water, heats it and feeds it to the taps. Apparently the UFH is connected to the same coil. Surely that means that water from your hot taps could be mixed with that running through the UFH pipes, unless there is some sort of hydraulic separation somewhere. It doesn't seem a very hygenic arrangement. I would be interested to hear others observations.

I hadn't , no. Cheers.

I confess my background is electrics, not plumbing. What I don't understand is that the heat store appears to have only one coil, which takes incoming mains pressure cold water, heats it and feeds it to the taps. Apparently the UFH is connected to the same coil. Surely that means that water from your hot taps could be mixed with that running through the UFH pipes, unless there is some sort of hydraulic separation somewhere. It doesn't seem a very hygenic arrangement. I would be interested to hear others observations.Sorry to ask again, but are you absolutely sure the UFH stops working if you turn the E7 off completely?
(probably not an experiment to do at this time of the year). The presence of the energy monitor is still bothering me

The plot thickens
Communal heat-pump system heats Gateshead apartments
GOING GREEN IN GATESHEAD - DIMPLEX COMMUNAL HEAT PUMP SYSTEM WARMS APARTMENTS

" Heat meters in each apartment can be remotely read, so that each owner pays only for the energy they use"

This second article has this added text

"The nine LA 28 AS air source heat pumps are arranged in two separate banks and provide heat to all apartments, which are arranged in three blocks. The innovative solution was specified, designed and installed by Dimplex heat pump installer partner Azure Natural Energy Systems and was completed in late 2009. Matthew Evans, owner of Azure, explains: “We looked at all the alternative renewable heating systems available, including ground source heat pumps, water to water heat pumps using heat from the River Tyne, biomass and solar thermal combinations. The most cost-effective solution was this communal air source heat pump system to deliver heating to the buildings, with domestic hot water served by individual, electrically heated cylinders"

 

[Basher]

I hadn't , no. Cheers.

The plot thickens
Communal heat-pump system heats Gateshead apartments
GOING GREEN IN GATESHEAD - DIMPLEX COMMUNAL HEAT PUMP SYSTEM WARMS APARTMENTS

" Heat meters in each apartment can be remotely read, so that each owner pays only for the energy they use"

This second article has this added text

"The nine LA 28 AS air source heat pumps are arranged in two separate banks and provide heat to all apartments, which are arranged in three blocks. The innovative solution was specified, designed and installed by Dimplex heat pump installer partner Azure Natural Energy Systems and was completed in late 2009. Matthew Evans, owner of Azure, explains: “We looked at all the alternative renewable heating systems available, including ground source heat pumps, water to water heat pumps using heat from the River Tyne, biomass and solar thermal combinations. The most cost-effective solution was this communal air source heat pump system to deliver heating to the buildings, with domestic hot water served by individual, electrically heated cylinders"

I think you might have found the answer, in which case no need to pursue dual rate electricity!

Air source heat pumps don't provide a particularly high temperature at this time of year, so best to keep the UFH ticking over.

If timed night setback and control of individual room temperatures is appealing, suggest obtaining the chrono module and finding someone to install it. Otherwise just fiddle with the thermostats as required!
Best regards.

 

[whatsthenews]

I think you might have found the answer, in which case no need to pursue dual rate electricity!

Air source heat pumps don't provide a particularly high temperature at this time of year, so best to keep the UFH ticking over.

If timed night setback and control of individual room temperatures is appealing, suggest obtaining the chrono module and finding someone to install it. Otherwise just fiddle with the thermostats as required!
Best regards.

I hope you don't think you're just going to disappear into the ether!
Thanks for the tip about keeping it ticking over.We've been wondering about how to use it most efficiently
I'm wondering how the billing works for a communal heating system because presumably it's not running off our meter?
Spotted a post on MSE forum that looked suspiciously like it might have been from a Friars Wharf resident. They were about the billing for the communal heating ASHP system for 85 flats. Guess what? The management company or building owner didn;t seem to know what they were doing. I don't think it's possible to work out how much each apartment has used. I bet there's been some interesting discussions at the residents meetings (if they have them)

Communal heat pump kWh cost

Hi, Hopefully a simple question regarding kWh costs in heat pump installations!..

forums.moneysavingexpert.com

 

[Basher]

I haven't disappeared yet, but please confirm we are talking about Friars Wharf, otherwise I'm going off at a tangent. No it's not running off your meter.

Here is a learned dissertation that just happens to mention how the Friars Wharf system, in general terms, is supposed to work, see page 113 figure 30 and beyond:

https://www.escholar.manchester.ac.uk/api/datastream?publicationPid=uk-ac-man-scw:224721&datastreamId=FULL-TEXT.PDF

Doesn't really help us answer your burning questions.

It appears the bank of 8 air source heat pumps run from 3-phase 440v. I don't imagine they would try to measure the electricity consumed by each flat, only the total for the building per month/quarter etc. It is the purpose of the energy meter in each flat to determine, on the basis of the flow through the water pipe, the incoming water temperature, and probably the outgoing water temperature, what the kWh equivalent of energy used is. They then hopefully attribute the contribution of each flat according to the energy meter readings in proportion to the total consumption, so each pays their 'share'. No doubt with an admin/management fee on top. But still according to a transparent rationale that flat owners are aware of.
I believe the heat output of the heat pumps should be roughly 3 times the electricity they use.
So assuming the meters in the flats are actually accurate, the following things should be true:
1) adding up all the flat meter readings for a given period and dividing by 3 should total approx the electricity bill for the building for that period (actually this is the way to find out the exact proprtion)
2) dividing by 3 the unit price per kWh for the heat pump supply, and multiplying by the number of units used by a flat, should be the bill for that flat, and adding all the flat's contributions should pay the overall bill.
Maybe someone got their sums wrong, not all the heat pumps were working properly, not all the kWh meters were working properly, or some other part of Murphy's Law came into play, and the landlord was out of pocket.
Well that's my theory!
I hope they know what their doing with their bills now. I would hope the heating charges would be less than half the 'equivalent normal' electricity bill would be.

There should be information about this in the Management Pack, Handbook or "Safety Manual", or whatever they've chosen to call it, or the lease, or other documentation for the property. Normally you sign to agree to the terms.

Nice flats!

 

[Basher]

Whatsthenews, I've just discovered another thread on this forum on the same system, from 2010!

How can I turn my underfloor heating on?

Hi, I bought an apartment recently that has underfloor heating installed, I've never really had to use it over the last few months since it's been warm and the apartment is very well insulated, however it's a bit chilly tonight so I thought I'd turn it on and see what it's like and have...

www.plumbersforums.net

 

[whatsthenews]

I haven't disappeared yet, but please confirm we are talking about Friars Wharf, otherwise I'm going off at a tangent. No it's not running off your meter.

Here is a learned dissertation that just happens to mention how the Friars Wharf system, in general terms, is supposed to work, see page 113 figure 30 and beyond:

https://www.escholar.manchester.ac.uk/api/datastream?publicationPid=uk-ac-man-scw:224721&datastreamId=FULL-TEXT.PDF

Doesn't really help us answer your burning questions.

It appears the bank of 8 air source heat pumps run from 3-phase 440v. I don't imagine they would try to measure the electricity consumed by each flat, only the total for the building per month/quarter etc. It is the purpose of the energy meter in each flat to determine, on the basis of the flow through the water pipe, the incoming water temperature, and probably the outgoing water temperature, what the kWh equivalent of energy used is. They then hopefully attribute the contribution of each flat according to the energy meter readings in proportion to the total consumption, so each pays their 'share'. No doubt with an admin/management fee on top. But still according to a transparent rationale that flat owners are aware of.
I believe the heat output of the heat pumps should be roughly 3 times the electricity they use.
So assuming the meters in the flats are actually accurate, the following things should be true:
1) adding up all the flat meter readings for a given period and dividing by 3 should total approx the electricity bill for the building for that period (actually this is the way to find out the exact proprtion)
2) dividing by 3 the unit price per kWh for the heat pump supply, and multiplying by the number of units used by a flat, should be the bill for that flat, and adding all the flat's contributions should pay the overall bill.
Maybe someone got their sums wrong, not all the heat pumps were working properly, not all the kWh meters were working properly, or some other part of Murphy's Law came into play, and the landlord was out of pocket.
Well that's my theory!
I hope they know what their doing with their bills now. I would hope the heating charges would be less than half the 'equivalent normal' electricity bill would be.

There should be information about this in the Management Pack, Handbook or "Safety Manual", or whatever they've chosen to call it, or the lease, or other documentation for the property. Normally you sign to agree to the terms.

Nice flats!

Yes, we're talking about Friars Wharf, and I really appreciate your input Basher. I didn't think about looking for academic papers. The management company , Zenith, are Manchester based

Now in possession of a meter reading at least (although knowing what we now know about the ASHP's, I'm a little reluctant to accept their reading. Would rather have eyes on the meter myself.)
.
I agree with your calculations and the presence of the heat meter makes sense now, although we've never been told that we will need to submit any readings or that anyone will need access to look at it We are keeping a check on it.
Is it correct to say that in the coldest months (now!) the COP will be lower than 3?
My parents has a house with an ASHP (air to air) in the US when we lived there. Generally although the winters were much shorter and sunnier, we had colder temps than here and they had an emergency back up "heater" that came on automatically when the temp went down to below about -4c and the pump couldn't raise the air temp' sufficiently to reach the set temp'.
We don't have an info pack nor any instructions for anything.
We've emailed the letting agent and told them we think the UFH runs off communal ASHP and asked how it's billed.
Thanks again!

 

[whatsthenews]

Whatsthenews, I've just discovered another thread on this forum on the same system, from 2010!

How can I turn my underfloor heating on?

Hi, I bought an apartment recently that has underfloor heating installed, I've never really had to use it over the last few months since it's been warm and the apartment is very well insulated, however it's a bit chilly tonight so I thought I'd turn it on and see what it's like and have...

www.plumbersforums.net

Just had a reply to our email. Apparently the landlord pays for the UFH in with the service charges. I'll take a loom at the thread.
Thanks again for helping us with the conundrum.

 

[whatsthenews]

Just had a reply to our email. Apparently the landlord pays for the UFH in with the service charges. I'll take a loom at the thread.
Thanks again for helping us with the conundrum.

Whatsthenews, I've just discovered another thread on this forum on the same system, from 2010!

How can I turn my underfloor heating on?

Hi, I bought an apartment recently that has underfloor heating installed, I've never really had to use it over the last few months since it's been warm and the apartment is very well insulated, however it's a bit chilly tonight so I thought I'd turn it on and see what it's like and have...

www.plumbersforums.net

yes, that's the same guy who posted in 2011 about the charges for the UFH (I posted the link a couple of posts ago). Doesn't sound like anyone knew what they were doing.
Sadly I can't see his photos. One guy states that the pump's in the wrong place!

 

[Basher]

Now in possession of a meter reading at least

i'm assuming you're talking here about the electricity supply to the flat, for hot water etc. Thats good news.
I hope the reading tallies reasonably with the last estimated bill! But of course that reading is nothing to do with the ASHP's and the UFH consumption.

As far as the UFH is concerned, the Rossweiner kWh meter should communicate readings back to a central unit. I believe all the flats readings would be logged centrally, or at least that would have been the case when the system was installed, probably integrated with some software that looks like nobody knew much about. Hopefully after all this time it's being done properly!

Thanks for the update. Hope things go smoothly at the flat.

 

[whatsthenews]

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The big guns