Underfloor Heating And Combi Boiler System

[SPECIAL LOCATION]

The grey signal wire could go to the orange terminal to signal boiler...

Is it that simple or am I over simplifying it??

Dave

Are you talking about a Grey from your UFH or the Grey on the 3port?

As the 3Port Grey is an INPUT to position the motor..

It is the Orange of the 3port that is the OUTPUT to fire the boiler when in the heating only position.

:C

 

[SPECIAL LOCATION]

Ok then, this seems quite simple to me! All I need is a signal from CH via from the stat via the programmer to the white valve wire or both white and grey.

Is it that simple or am I over simplifying it??

Dave

Not clear what you mean by a signal to white or both grey & white ?

are you referring to one signal source or two signal sources..?

Sometimes find it helps to do a quick logic table to verify each of your operational states does do what you want it to do..

i.e. you have 4 possible scenarios of Heat/UFH on/off.

and you have got to position a valve and fire a boiler correctly for each..

Check your proposed arrangement with the standard typical Heat & water arrangement for the 3port & bolier..

e.g.



dunno if that helps..

or confuses the matter??

opcorn

 

[ProDave]

I've been away for a few days, so not read all the thread.

To save yourself a LOT of grief, re plumb it with 2 port valves.  One for radiators, one for hot water and one for UFH.

Then each system is independent and simple to work on and diagnose.  Each system turn on and opens it's 2 port valve when it calls for heat.  then the feedback contact for each of the 2 port valves are wired in parallel, so id any one of the systems calls for heat it's valve opens and the boiler fires.

You could be chasing this for days with 3 port valves unless you have a thorough understanding of how they work, plus they are not perfect so you often get a bit of water bypassing to the wrong circuit when it shouldn't. 3 port valves are the work of the devil.

 

[SPECIAL LOCATION]

To save yourself a LOT of grief, re plumb it with 2 port valves.  One for radiators, one for hot water and one for UFH.

The op has had the boiler replaced with a combi so no need for a water valve..

He was just trying to utilise what was already there rather than the expense of modifying pipes and buying more valves...

when with just a bit of wiring he should be able to get what he wants..

i.e. two zones controlled from an existing 3port valve!

it isn't that difficult to do.

.

 

[ProDave]

The op has had the boiler replaced with a combi so no need for a water valve..

He was just trying to utilise what was already there rather than the expense of modifying pipes and buying more valves...

when with just a bit of wiring he should be able to get what he wants..

i.e. two zones controlled from an existing 3port valve!

it isn't that difficult to do.

.

3 port valves are designed to be used for heating and hot water, and need a Hot water OFF signal to work.

No doubt you could get one to work with two heating zones instead, but that would mean one zone would need to provide a "Heating off" signal.

I doubt you will find an UFH manifold controller that provides a heating off signal. So you can't use the HW output of the 3 port valve for the UFH side.

So if you used the HW port of the 3 port valve for the radiators (and the heating port for the UFH) you might be able to get it to work as you can usually get a heating off signal from the programmer for that for the radiators. But if you have a room thermostat for the radiators you would have to get one with a changeover contact (same as the HW thermostat is a changeover contact), which might be tricky.

I would hardly say for a novice that it wasn't tricky to do.

for a little bit of plumbing two 2 port valves would give a better solution. but that's just my opinion.

you would need to start by drawing a circuit diagram including all the components including programmers, UFH manifold controllers, thermostats etc.

EDIT

Just read more of the thread. Seems like many people before me have told you to ditch the 3 port and fit two 2 port valves. Looking at your picture, it's a pretty simple swap to do that, you have plenty of space and it will take a plumber about an hour I would guess, a bit more allowing for draining and re filling.

What's that thing with a flow meter built in between the flow and return?

And I haven't seen the quesion answered so I'll ask it again, is there a mixer valve anywhere to reduce the flow temperature to the UFH pipes?

 

[dave2]

Just looking at your picture.

Do you have a mixing valve somewhere in the system?

 

[SPECIAL LOCATION]

3 port valves are designed to be used for heating and hot water, and need a Hot water OFF signal to work.

I have already explained this back on posts #56 & #63

No doubt you could get one to work with two heating zones instead, but that would mean one zone would need to provide a "Heating off" signal.

I doubt you will find an UFH manifold controller that provides a heating off signal. So you can't use the HW output of the 3 port valve for the UFH side.

So if you used the HW port of the 3 port valve for the radiators (and the heating port for the UFH) you might be able to get it to work as you can usually get a heating off signal from the programmer for that for the radiators. But if you have a room thermostat for the radiators you would have to get one with a changeover contact (same as the HW thermostat is a changeover contact), which might be tricky.

I would hardly say for a novice that it wasn't tricky to do.

Just about as tricky for a novice as replacing the 3port valve with 2port valves..

for a little bit of plumbing two 2 port valves would give a better solution. but that's just my opinion.

you would need to start by drawing a circuit diagram including all the components including programmers, UFH manifold controllers, thermostats etc.

EDIT

Just read more of the thread. Seems like many people before me have told you to ditch the 3 port and fit two 2 port valves. Looking at your picture, it's a pretty simple swap to do that, you have plenty of space and it will take a plumber about an hour I would guess, a bit more allowing for draining and re filling.

I would hazard a guess that modifying a bit of wiring (maybe including a relay) is a simple alteration to do and would take an electrician about an hour..

and quite probably be cheaper overall!

What's that thing with a flow meter built in between the flow and return?

And I haven't seen the quesion answered so I'll ask it again, is there a mixer valve anywhere to reduce the flow temperature to the UFH pipes?

I think the OP implied this in post #19

copy post#19

Im lead to believe the UFH cycles water with it own pump. a thermostate set to max 45 deg allows CH water to enter the cycle if needed, so UFH never exceeds 45 deg and CH is only called for if room temp drops. I think there is a pressure relief between the flow and return should the boiler be pumping and no flow required???

(Me Red above)

No doubt two the 2port valves option is a solution...

But it still may be cheaper to modify the existing wiring...

As I understand it the OP has builders/Plumbers/Electricians involved already who are now wrangling over who's to blame and who pays what...

why introduce greater expense of valves and pipes when cables and possibly relays are cheaper?

Give the OP details of both possible solutions so they can make up their own mind..

rather than us telling them you must do it one way.

Guinness

 

[steptoe]

(Me Red above)

No doubt two the 2port valves option is a solution...

But it still may be cheaper to modify the existing wiring...

As I understand it the OP has builders/Plumbers/Electricians involved already who are now wrangling over who's to blame and who pays what...

why introduce greater expense of valves and pipes when cables and possibly relays are cheaper?

Give the OP details of both possible solutions so they can make up their own mind..  there are at least 8 possible solutions I can think of easily

rather than us telling them you must do it one way.

Guinness

some of which I mention many posts ago,

myself and Andy also mentioned many many posts ago that the 3port valve required an OFF signal

I dont see that relays are going to be simply or cheap in this scenario,

the installers [as they clearly arent tradesmen in this field] have no idea wht they are doing, so they are going to be totally lost with relays etc.

I already suggested fitting a QE2 [or similar] and appropriate stats, as they have an off signal available,

to me, that is by far the easiest solution available in keeping the 3port valve,

3 port valves are designed to be used for heating and hot water, and need a Hot water OFF signal to work.

I have already explained this back on posts #56 & #63

mentioned back at post #28

 

[SPECIAL LOCATION]

some of which I mention many posts ago,

myself and Andy also mentioned many many posts ago that the 3port valve required an OFF signal

Indeed you did and I also said you did back in earlier posts..... :Salute

Either way the crux of the problem as I read it, (and Step's & Andy have already pointed out), is that domestic heating wiring is NOT complicated..

as long as you understand what you want a system to do..  and you also understand how the components you have got work..

I dont see that relays are going to be simply or cheap in this scenario,

the installers [as they clearly arent tradesmen in this field] have no idea wht they are doing, so they are going to be totally lost with relays etc.

Dunno where you are buying your relays from..

But I can get them much cheaper than 2-port valves!

The point is...

some are making assumptions that these other persons and/or the OP will never be able to fathom out the mystery of a relay..?

maybe that is true..  OR   maybe it isn't..?

who am I to say what they can or cannot do..?

Perhaps they just need to be shown or explained whats needed and they could actually do it!

It could be that they just didn't understand the 3port valve bit?

and just needed it explaining to them..

Just as we all had to learn various concepts for the first time at some point...

but on the other hand...

you may be right and we would all be wasting our time trying to help anything!

a simple changeover 2-way contact could create an UFH on or UFH off voltage without too much rocket science.

And I am guessing many of us on here could make a relay box with some labeled up wago connectors inside it then post it to the OP and tell him where to connect what..

Makes you wonder why bother trying to answer anything on a forum as by definition all the questioners are thick, (so they could never understand what we say), or they wouldn't need to ask in the first place would they?

:coat

 

[ProDave]

My point is the 3 port valve is a surprisingly complicated bit of kit.  Okay if you UNDERSTAND it. but most people just wire it up parrot fashion "the brown wire goes to..." etc without understanding anything.  If you wire it that way and it doesn't work, you will have a job fault finding.

To get this working with a 3 port valve is definitely non standard. In order to understand it you must first draw a circuit diagram, then connect it. If it doesn't work you can fault find from your drawing.

It does sound like the people doing the job don't have the knowledge to do that.

So I simply suggested 2 port valves are a lot easier to understand and fault find, as there's no complicated interaction between the different systems.

But then I got told off for trying to help. you can't win them all.   :coat

 

[steptoe]

My point is the 3 port valve is a surprisingly complicated bit of kit.  Okay if you UNDERSTAND it. but most people just wire it up parrot fashion "the brown wire goes to..." etc without understanding anything.  If you wire it that way and it doesn't work, you will have a job fault finding.

To get this working with a 3 port valve is definitely non standard. In order to understand it you must first draw a circuit diagram, then connect it. If it doesn't work you can fault find from your drawing.

It does sound like the people doing the job don't have the knowledge to do that.

So I simply suggested 2 port valves are a lot easier to understand and fault find, as there's no complicated interaction between the different systems.

But then I got told off for trying to help. you can't win them all.   :coat

PD,

I agree, as I posted earlier with varying suggestions as to how it could be done,

and, IMHO [which prob doesnt amount to much apparently], is that the correct way to get this system working properly and efficiently is a 2channel [or 2x 1ch] programmer, 2 stats, and 2 x 2port valves.

there are other permutations that will get it to work, but as the installers have already had numerous failed attempts at it,

Im lost as to how they are ever going to figure out how to do it by adding relays etc into the mix.

 

[SPECIAL LOCATION]

Ideal world money & time no object..

then rip the stuff out and put in 2port valves..

rewire as appropriate...

BUT..

taking a wild guess at how the commercial real world works...

Some kit is there that can do the job... as numerous professionals have confirmed..

2 x 2 port valves are better, but, there is absolutely no reason this will not work with a mid position valve,  you simply need it connected up properly, You will need 2 stats,  1 for ufh and 1 for ch 

it can be done easily... output from CH of boiler into middle of 3 port valve. one side to UHF, other side to normal CH. 2 channel programmer used with 'hot water' side doing UHF, CH doing CH. no control for DHW other than the normal on/off switch on the boiler. fairly simple really.

looks like another example of plumber / electrician not knowing a thing about how heating systems work

This should work,,,, unless they've installed a priority type 3 port valve instead of a mid position one.
I would however say that a S plan is far superior

etc.. etc..

Who is covering the costs of extra valves etc..?

from reading the OPs comments it does give the impression first choice was to get working what was already there...

Only opted for a Y plan because the existing valve wasnt that old. Plumber just used what was available and I didnt know any better. By the time im finished I'll be an expert, (and the wife, shes not too happy its taken this long to sort out !!)

Dave

Thanks for the kind offer, but Ive paid someone a lot of money and there going to fix it. Im just doing my research so I can get them to do what ive paid for. failing that I'll be in the market for a good engineer soon....

I doubt the builder/plumber or electrician will donate valves and the extra labour for free to modify the system to accommodate them..?

The three port valve is not that blinkin complicated...

Its just that fact that you need a voltage when something is OFF not ON that throws a lot of people!!

If we can't try and help people with a three port valve then by that logic we may as well say don't even consider any 2-way light switch questions either..

best just tell them to wire up two single lamps off 1-way switches..

far easier to fault find if they take down the landing light!!

:shakehead

 

[steptoe]

Ideal world money & time no object..

then rip the stuff out and put in 2port valves..

rewire as appropriate...

BUT..

taking a wild guess at how the commercial real world works...

Some kit is there that can do the job... as numerous professionals have confirmed..

etc.. etc..

Who is covering the costs of extra valves etc..?

from reading the OPs comments it does give the impression first choice was to get working what was already there...

I doubt the builder/plumber or electrician will donate valves and the extra labour for free to modify the system to accommodate them..?

The three port valve is not that blinkin complicated...

Its just that fact that you need a voltage when something is OFF not ON that throws a lot of people!!

If we can't try and help people with a three port valve then by that logic we may as well say don't even consider any 2-way light switch questions either..

best just tell them to wire up two single lamps off 1-way switches..

far easier to fault find if they take down the landing light!!

:shakehead

well, if it was my house then they would be made to get the system working properly ,

if they have been paid to do it then any extra expense is their problem, not mine.

its seems from th OP that they dont understand how to get a 3port valve working in this situation, even though it is perfectly viable, so if they dont understand how to get it to work as is, then any extra expense is their problem, not the OPs.

 

[davenellie]

Guys I would like to thank you all for your time and opinions, I started the thread as a concussed home owner being bambusled by his builder. I now have the second opinion I needed and almost enough knowledge to sort this myself. But as the last posts suggests, I have already paid a lot of money to a tradesman for working UFH!!!! A little research on here has taught me utilising the 3 port valve is the tricker solution and 2x2 port valves would be easy to do. I don't see why I should have to pay any more for this to be sorted out but I now feel confident in getting the builder to at no further expense to myself. I didn't sign up for this hassle when I commissioned the extension. I have probably contributed to the issue by asking plumber to utilise the 3 port valve. It was relatively new. It was obviously asking too much of my builder/ electrician! Just a shame they don't frequent forums! Your right of course I'm competent but not confident to tackle this myself from solutions posted on here but it does give me the confidence to speak to my builder! For that I thank you all for your invaluable contributions.

Dave

 

[Sharpend]

Blinding feed back there Dave, I'm sure all will appreciate. Hope you get it sorted.

 

[ProDave]

You could always print some of the suggestions on this thread and hand it to the installers.

 

[Andy™]

strange how his 'electrician' cant get it working, yet everyone who has replied here knows exactly how to do it. and many different methods

 

[SPECIAL LOCATION]

Guys I would like to thank you all for your time and opinions, I started the thread as a concussed home owner being bambusled by his builder. I now have the second opinion I needed and almost enough knowledge to sort this myself. But as the last posts suggests, I have already paid a lot of money to a tradesman for working UFH!!!! A little research on here has taught me utilising the 3 port valve is the tricker solution and 2x2 port valves would be easy to do. I don't see why I should have to pay any more for this to be sorted out but I now feel confident in getting the builder to at no further expense to myself. I didn't sign up for this hassle when I commissioned the extension. I have probably contributed to the issue by asking plumber to utilise the 3 port valve. It was relatively new. It was obviously asking too much of my builder/ electrician! Just a shame they don't frequent forums! Your right of course I'm competent but not confident to tackle this myself from solutions posted on here but it does give me the confidence to speak to my builder! For that I thank you all for your invaluable contributions.

Dave

:Applaud   :Salute

Do come back and update us with the final solution you finally end up with.. 

As you say...

It can be done...

Various options...

You just need to go and kick some ass to get builder/plumber/electrician or any combination thereof to do the work you have paid for!

Guinness

 

[davenellie]

Electrician came round today. Rewired the junction box! I now have CH switching valve to Mid position and UFH by default when CH not on. I've tried different combos of switching UFH on and then CH, then switching it off again to check the valve operates. It seems to work ok but only occasionally if the CH clicks off the valve doesn't move leaving both CH and UFH hot. I've tried different combos but can't work out which leaves the valve at both when just the UFH is calling!

Another issue is when the CH and UFH turn off it takes between 2-3min before the boiler turns off! Is this normal or is the boiler self protection turning it off not actual off signal?

Electrician hasn't been in touch to let me know what he has done so I took the photo for the record. The bodge seems to continue, no relays no extra wires... Not sure what I expected but I think I'm living with a dotched compromise!

Dave...

 

[davenellie]

I believe there is a mixing valve at the UFH manifold. Limited to 45deg max. Struggling to post pic of jct box. File to large I think!