changing from ufh to Rads

Ah Here · 22-02-2014 10:06pm #1

Hi everyone.

Im on the verge of tears with my underfloor heating system. I installed it 5 years ago in my 2500ft dormer. I rarely have it on upstairs, and to heat the downstairs (1700ft) is costing the bones of €2500 a year in oil. We dont have it on too high- around 18 degrees average - and the boiler is serviced regularly.

I feel that that is way to high an annual heating bill. I have the house well insulated with triple glazed windows. How much would it cost, and how difficult would it be, to install rads downstairs instead of the ufh?

Thanks in advance!

Dtp1979 · 22-02-2014 10:36pm

Ah Here wrote: »

Hi everyone.

Im on the verge of tears with my underfloor heating system. I installed it 5 years ago in my 2500ft dormer. I rarely have it on upstairs, and to heat the downstairs (1700ft) is costing the bones of €2500 a year in oil. We dont have it on too high- around 18 degrees average - and the boiler is serviced regularly.

I feel that that is way to high an annual heating bill. I have the house well insulated with triple glazed windows. How much would it cost, and how difficult would it be, to install rads downstairs instead of the ufh?

Thanks in advance!

I'd say your money would be better spent on trying to rectify the UFH problem.
Did you get anybody out to look at the system you currently have?

shane0007 · 22-02-2014 10:36pm

It is possible but there maybe correctable errors with your existing setup. This is very common & could possibly be a far cheaper option than changing to rads.

Ah Here · 22-02-2014 10:49pm

We've fixed some issues already- the installation was poor and the plumber had put actuators on the wrong zones etc. What else should i be looking out for? My plumber also took out the timer clock we had so now we have 24hr hot water. Could this also be an issue?

Thanks for your help!

shane0007 · 22-02-2014 10:56pm

Yes that is a big issue.
I bet you have a lot more issues with the UFH side also.any I come across are set up terribly.

Ah Here · 22-02-2014 11:01pm

shane0007 wrote: »

Yes that is a big issue.
I bet you have a lot more issues with the UFH side also.any I come across are set up terribly.

Thanks Shane. I dunno what else to look out for. Do you know of anyone good in kerry who would be able to have a look at it?

shane0007 · 22-02-2014 11:08pm

Sorry no, not in Kerry but somebody else here may do.
There is really too many checks & overall visuals to do that could not be done on a forum.

Ah Here · 22-02-2014 11:12pm

shane0007 wrote: »

Sorry no, not in Kerry but somebody else here may do.
There is really too many checks & overall visuals to do that could not be done on a forum.

Ok thanks, hopefully someone else will come along

Dtp1979 · 22-02-2014 11:44pm

How many Kerry men does it take to fix a UFH system?
Sorry, couldn't resist

Dtp1979 · 22-02-2014 11:45pm

On a serious note though, I'd put a timer and thermostat on the hot water side to start

Cedrus · 23-02-2014 12:03am

Ah Here wrote: »

We've fixed some issues already- the installation was poor and the plumber had put actuators on the wrong zones etc. What else should i be looking out for? My plumber also took out the timer clock we had so now we have 24hr hot water. Could this also be an issue?

Thanks for your help!

I'd start by taking out your plumber(s).
I can't comment on the zoning without knowing more detail, 24 hour hot water availability is fantastic (if you need it) but 24 hour heating of water is a disaster.

How are your zones set up, are there room thermostats and timers for each zone.

2500ft is a beefy enough house, not huge, but bigger than most of us grew up in and it will take more to heat. You say you don't have it on upstairs, but how are the floors separated, if you don't have sufficient insulation/separation then you are heating upstairs regardless.

Ah Here · 23-02-2014 10:09am

There is both insulation between the ceiling joists and below the easyscreed upstairs so it is well insulated.

The downstairs is seperated into 8 zones each controlled by a stat which is normally set at 18 degrees. Some of the zones are much larger than others. When the system was first installed there was a timer clock on it one seperated into downstairs, upstairs and hot water but this was taken out as according th the rep from pulsar the system wasnt suitable for a timer. This leaves me with no was to control the hot water and also no way to time the heating, but as i wass told that ufh works best and most efficientl when on constant instead of turning it off and on whenever its needed im ok with that.

Its an oil condensing boiler we have. The manifold is in the centre of the house, and one other thing the rep did was he disconnected a temp cut off stat on the mainifold as it was switching the system off once it got to a certain temp.

shane0007 · 23-02-2014 10:16am

These are some questions you should be asking.
Is the UFH on constant?
Is it interlocked with the boiler so that when the last loop is satisfied it switches off the boiler?
Has the boiler a separate timeclock to the UFH or is it called in by the UFH control centre?
How many room thermostats do you have controlling the system?
What is the mixing valve temp set to?
What are the loop flow temps at compared to the return loop temps?
Are they zone valves separating zone manifolds?
When it was installed, what thickness insulation was installed in the floor & was it turned up around the perimeter of rooms?
Is the boiler a standard efficiency or high efficiency?
How often is it serviced & do you get a flue gas analysis print out everytime on completion of the service?
What is the kw output of the boiler?

Ah Here · 23-02-2014 12:10pm

These are some questions you should be asking.
Is the UFH on constant? YES
Is it interlocked with the boiler so that when the last loop is satisfied it switches off the boiler? I THINK SO
Has the boiler a separate timeclock to the UFH or is it called in by the UFH control centre? DON'T KNOW
How many room thermostats do you have controlling the system? 8
What is the mixing valve temp set to? 40 DEGREES
What are the loop flow temps at compared to the return loop temps? DONT KNOW
Are they zone valves separating zone manifolds? SOME ZONES HAVE TWO ACTUATOR VALVES
When it was installed, what thickness insulation was installed in the floor & was it turned up around the perimeter of rooms? 100MM UNDER AND 25MM AROUND THE SIDES
Is the boiler a standard efficiency or high efficiency?
How often is it serviced & do you get a flue gas analysis print out everytime on completion of the service? ONCE A YEAR AND NO
What is the kw output of the boiler?
ITS A FIREBIRD C26 AND IT SAYS 21.6 -42KWS

THANKS

shane0007 · 23-02-2014 12:50pm

By the sounds of it, you wouldn't have to spend a lot to majorly reduce your consumption.
When I mentioned zone valves, I meant motorised valves & not loop actuators. The zone valves would stop heat going through to manifolds are not requiring heat, but the actuators would be.
Time control over each manifold would be of great benefit.
Time control with a motorised valve & cylinder stat is a must for the hot water cylinder.
Time control over the manifold or Heatmiser's set back stats are great.
Boiler service with an analyiser print out is a must as the boiler could be way off. Firebird C26 would be no harm to service more frequently but by somebody who understands them.

Ah Here · 23-02-2014 12:59pm

Thanks a mill Shane,

Sounds like i need to get a ufh expert in allright. Pulsar are gone bust so they are no good to me.

By time control do you mean not having the heating on constant?

Dtp1979 · 23-02-2014 1:05pm

Ah Here wrote: »

Thanks a mill Shane,

Sounds like i need to get a ufh expert in allright. Pulsar are gone bust so they are no good to me.

By time control do you mean not having the heating on constant?

Guardian solutions have pretty much taken over the old pulsar brand. I've no number as I don't use their stuff. I think they're based in cork

oikster · 23-02-2014 1:09pm

Sounds to me more like a serious shortage of pipework. If your UF loops are not sufficient to heat the areas they are in then the stats will never be satisfied.This is probably why you are burning so much oil and not getting results. The heat has to be going somewhere. See below:

Its an oil condensing boiler we have. The manifold is in the centre of the house, and one other thing the rep did was he disconnected a temp cut off stat on the mainifold as it was switching the system off once it got to a certain temp.

Ah Here · 23-02-2014 1:30pm

oikster wrote: »

Sounds to me more like a serious shortage of pipework. If your UF loops are not sufficient to heat the areas they are in then the stats will never be satisfied.This is probably why you are burning so much oil and not getting results. The heat has to be going somewhere. See below:

Its an oil condensing boiler we have. The manifold is in the centre of the house, and one other thing the rep did was he disconnected a temp cut off stat on the mainifold as it was switching the system off once it got to a certain temp.

the rooms are heating up sufficently

oikster · 23-02-2014 1:33pm

After how long and for how long.

oikster · 23-02-2014 1:36pm

Shane asked a question about return temperatures,you need to find this out.

Ah Here · 23-02-2014 1:52pm

thanks oikster, I need to find someone in Kerry who will sort me out, most of the plumbers who've had a look at it are chancing their arm

oikster · 23-02-2014 1:59pm

Just out of interest,what type of screed did you use and to what depth?

Ah Here · 23-02-2014 2:01pm

oikster wrote: »

Just out of interest,what type of screed did you use and to what depth?

Concrete downstairs and easycreed upstairs, cant remember the depth

timmy4u2 · 23-02-2014 2:02pm

Ah Here wrote: »

thanks oikster, I need to find someone in Kerry who will sort me out, most of the plumbers who've had a look at it are chancing their arm

Is there a guy someplace around Rathmore named Tim Cremin. He invinted the oxyvent. Supposed to be a good plummer.
All of my friends who have either UFH or pellet fired heating are regretting having either of those systems installed.
Thankfully I shied away from those systems at the time.
Before Christmas I fitted Solo Rads and whereas I have not yet done everything as it should have been they have been a massive success.
Great heat and a big reduction in my fuel bill

oikster · 23-02-2014 2:03pm

When you say easyscreed,is this a liquid screed like say from Larsen or such.

SpaceTime · 23-02-2014 2:07pm

Get it checked out but those bills may not be out of line with normal.

Our radiator based system isn't too efficient but due to endless gas price hikes we're getting to the stage that we need to cut back on heating.

Unfortunately is as much a symptom of bad governance as bad plumbing

You'd want to maybe look at how many litres of oil you're using rather than the price and compare with previous years.

Definitely get the system checked out though and compare your usage with similar sized homes.

I've found a lot of people are actually unaware of their annual heating costs as they often just don't add them up and operate month to month.

€208 per month isn't that unusual for a house that size.

You could maybe look at other cheaper fuels like wood pellet etc?

shane0007 · 23-02-2014 2:09pm

oikster wrote: »

Sounds to me more like a serious shortage of pipework. If your UF loops are not sufficient to heat the areas they are in then the stats will never be satisfied.This is probably why you are burning so much oil and not getting results. The heat has to be going somewhere.

Not necessarily as if the zones are satisfied, there will be little draw from the 70C loop & the boiler will be constantly on top of the demand, leading to constant short cycling of the boiler. This is the worst condition for a condensing boiler, especially a Firebird.

IMO, the system seems to be ok. The controls are terrible.
Two options:
1. Upgrade the controls completely to something such as the Heatmiser as they are better for UFH as they are not on/off controls as such, but rather a desired temperature during a timed period. Add motorised valves to each manifold & dhw circuits. Timed control for the HW can be done through one of the Heatmiser PRT-HW stats, usually in the kitchen.
2. All of 1. but also add in a small buffer tank/thermal store. The boiler will heat the buffer but called in via a Resol TT1. This allows 2no call points so if buffer falls below 40C, boiler will fire & switches off once 70C is reached. HW circuit would be via a 3 port diverted valve bypassing the buffer. Buffer only feeds the UFH.
Timed controlled UFH with temperature determined time periods rather than on/off periods works far better & more economical.

That's my opinion anyhow.

oikster · 23-02-2014 2:14pm

A simple check of return temps and time taken for zones to reach temp will verify correct system sizing before spending on controls.

shane0007 · 23-02-2014 2:16pm

A house of 2,500sqft with UFH should not be using €2,500 worth of oil per heat for heating & hot water. Hot water will be taking about €700 depending on number of users & volume used, so that leaves approx €1,800 for heating.
I have a 3,000sqft house & last year it cost me €1,000 for heating. It will probably hit €200 for hot water but I have a different set up than most.

Ah Here · 23-02-2014 2:21pm

shane0007 wrote: »

A house of 2,500sqft with UFH should not be using €2,500 worth of oil per heat for heating & hot water. Hot water will be taking about €700 depending on number of users & volume used, so that leaves approx €1,800 for heating.
I have a 3,000sqft house & last year it cost me €1,000 for heating. It will probably hit €200 for hot water but I have a different set up than most.

Sound point out i have a solar panel for hot water aswell.

Ah Here · 23-02-2014 2:32pm

shane0007 wrote: »

Not necessarily as if the zones are satisfied, there will be little draw from the 70C loop & the boiler will be constantly on top of the demand, leading to constant short cycling of the boiler. This is the worst condition for a condensing boiler, especially a Firebird.

IMO, the system seems to be ok. The controls are terrible.
Two options:
1. Upgrade the controls completely to something such as the Heatmiser as they are better for UFH as they are not on/off controls as such, but rather a desired temperature during a timed period. Add motorised valves to each manifold & dhw circuits. Timed control for the HW can be done through one of the Heatmiser PRT-HW stats, usually in the kitchen.
2. All of 1. but also add in a small buffer tank/thermal store. The boiler will heat the buffer but called in via a Resol TT1. This allows 2no call points so if buffer falls below 40C, boiler will fire & switches off once 70C is reached. HW circuit would be via a 3 port diverted valve bypassing the buffer. Buffer only feeds the UFH.
Timed controlled UFH with temperature determined time periods rather than on/off periods works far better & more economical.

That's my opinion anyhow.

Do i understand from that that u think the heating shouldnt be on constant?

shane0007 · 23-02-2014 3:04pm

Ah Here wrote: »

Do i understand from that that u think the heating shouldnt be on constant?

Yes. With Heatmiser's stat or a similar one, you set the time zone, example 8pm - 11pm as 19C, then you set 11pm - 7am as 16 or 17C and so on. The UFH is not off as such but rather the stat is satisfied more often.
It can lead to enormous savings. The other advantage you have is that you have Easiscreed. Easiscreed heats up much faster than normal concrete mixes so it will be more suitable to this type of control as it will achieve temperature much faster. It looses much faster also but with the temperature only reduces it will not be too far off.

Ah Here · 23-02-2014 3:36pm

shane0007 wrote: »

Yes. With Heatmiser's stat or a similar one, you set the time zone, example 8pm - 11pm as 19C, then you set 11pm - 7am as 16 or 17C and so on. The UFH is not off as such but rather the stat is satisfied more often.
It can lead to enormous savings. The other advantage you have is that you have Easiscreed. Easiscreed heats up much faster than normal concrete mixes so it will be more suitable to this type of control as it will achieve temperature much faster. It looses much faster also but with the temperature only reduces it will not be too far off.

I only have easycreed upstaors not downstairs

shane0007 · 23-02-2014 5:49pm

Ah Here wrote: »

I only have easycreed upstaors not downstairs

That won't be a problem. Easiscreed is more suitable for upstairs anyhow as bedrooms require less reaction time. Downstairs is better with more thermal mass.

As I said, I don't think your parameters are incorrect. It's more of a control issue & in answer to your original question, I wouldn't change to rads, change the controls.
I have UFH since 2003 & certainly wouldn't change. Much more comfortable living with UFH over rads, but you've probably realised that with your own.

Since you have solar, your oil consumption for HW is probably in the region of €450 - €500 so your UFH costs is approx €2,000 - €2,050. Very easy to reduce that so long term, anything you spend will be recouped very quickly.

oikster · 23-02-2014 6:04pm

Shane you asked for return temps for this system. You did not receive an answer. You originally stated that it would not be easy to diagnose the problem without all the info. You now deem this install to be perfect without all info and are advising OP to spend more money. You do not know the depth of concrete on the ground floor. You do not know the length of the loops in this system. You do not know how long it takes the system to heat up. You tell the OP that the system shouldn't run constantly and then recommend a system that has the system constantly calling for heat.What size of buffer do you recommend. Why are you recommending a buffer. And finally is concrete really better than liquid screed .

shane0007 · 23-02-2014 6:43pm

oikster wrote: »

Shane you asked for return temps for this system. You did not receive an answer. You originally stated that it would not be easy to diagnose the problem without all the info. You now deem this install to be perfect without all info and are advising OP to spend more money. You do not know the depth of concrete on the ground floor. You do not know the length of the loops in this system. You do not know how long it takes the system to heat up. You tell the OP that the system shouldn't run constantly and then recommend a system that has the system constantly calling for heat.What size of buffer do you recommend. Why are you recommending a buffer. And finally is concrete really better than liquid screed .

That's a lot in one mouthful :-)
I did indeed ask those. By experience, nearly all systems are designed on a CAD system specifically with the heat source in mind & laid in that manner. When I see certain important parameters adhered to & the trouble & expense of Easiscreed used, I would be surprised if other parts of the installation were scrimped on.
The OP never stated a poor heat from the system, it was more of a running cost issue, to the point where they are considered abandoning the UFH & going with rads. That ain't going to be cheap.
Also by experience, where I find expensive running costs on UFH being heated by an oil boiler is generally down to poor controls.
I did ask for flow & return temps & OP said flow was 40C which is fine. Return temp would be handy to know & if coming in at circa 29-30C, then manifold overall is balanced which would imply the individual flow rated won't be that far out.
Ground floor concrete depth will most likely be 75mm.
I did not recommend installing a system that is constantly calling for heat. It will set back to a lower desired room temp & as the OP stated the house is very insulated, the temp drop in the house over a few hours should not drop dramatically.
Buffer tank size, I did not go into great detail as not many people have the room for them, but generally I personally, for oil, would never go above 500 litres. This will give for an average house demand of circa 50w per sqm approx 90 - 120 minutes of heat for an input of approx 45 minutes (that's from cold).
The buffer tank is our source of modulation. If we can ever get a modulating oil boiler, we won't need a buffer with an oil boiler. Until then, a buffer makes for very low wastage of our boiler runtime & no over-firing, for example, OP's existing demand for UFH is 232sqm x 50 watts = 11.6kw. System losses will be minimal as they are lost to the floor so it's only pipework to manifolds. C26 will most likely be firing at factory setting of 23kw. Double the required, so will be short cycling like mad. Answer: a buffer! Heat the buffer, draw the low demand as required. Lowest allowable temp of buffer will be 40C.

Take the HW demand directly from the boiler when required, perhaps 30 mins in the morning & 30 mins in the evening. Use the diverted valve for this.

oikster · 23-02-2014 6:54pm

Seeing as you started your post with an insult I will keep my reply brief. I have read your post and words like "if", "circa" and "likely" tell me all I need to know.

Wearb · 23-02-2014 6:54pm

Interesting thread.

I would have preferred it if my (this one) post had gotten into post #38 position.

shane0007 · 23-02-2014 7:02pm

oikster wrote: »

Seeing as you started your post with an insult I will keep my reply brief. I have read your post and words like "if", "circa" and "likely" tell me all I need to know.

If you took that as an insult, then you should try & work out what smiley faces are used for. No need for crap.
If the OP does not require or want my advice then I won't post again or perhaps you are just looking for an argument.

Wearb · 23-02-2014 7:10pm

oikster wrote: »

Seeing as you started your post with an insult I will keep my reply brief. I have read your post and words like "if", "circa" and "likely" tell me all I need to know.

AH HERE! oikster

pat35 · 23-02-2014 7:37pm

shane0007 wrote: »

That won't be a problem. Easiscreed is more suitable for upstairs anyhow as bedrooms require less reaction time. Downstairs is better with more thermal mass.

As I said, I don't think your parameters are incorrect. It's more of a control issue & in answer to your original question, I wouldn't change to rads, change the controls.
I have UFH since 2003 & certainly wouldn't change. Much more comfortable living with UFH over rads, but you've probably realised that with your own.

Since you have solar, your oil consumption for HW is probably in the region of €450 - €500 so your UFH costs is approx €2,000 - €2,050. Very easy to reduce that so long term, anything you spend will be recouped very quickly.

Shane, The oil the boiler is heating the HW cylinder 24/7 to say 60 degrees is there any savings by having the solar at all.If even having time clock/controls for HW could there be a saving of upto 300 euro+ pa?

Ah Here · 23-02-2014 7:43pm

shane0007 wrote: »

That's a lot in one mouthful :-)
I did indeed ask those. By experience, nearly all systems are designed on a CAD system specifically with the heat source in mind & laid in that manner. When I see certain important parameters adhered to & the trouble & expense of Easiscreed used, I would be surprised if other parts of the installation were scrimped on.
The OP never stated a poor heat from the system, it was more of a running cost issue, to the point where they are considered abandoning the UFH & going with rads. That ain't going to be cheap.
Also by experience, where I find expensive running costs on UFH being heated by an oil boiler is generally down to poor controls.
I did ask for flow & return temps & OP said flow was 40C which is fine. Return temp would be handy to know & if coming in at circa 29-30C, then manifold overall is balanced which would imply the individual flow rated won't be that far out.
Ground floor concrete depth will most likely be 75mm.
I did not recommend installing a system that is constantly calling for heat. It will set back to a lower desired room temp & as the OP stated the house is very insulated, the temp drop in the house over a few hours should not drop dramatically.
Buffer tank size, I did not go into great detail as not many people have the room for them, but generally I personally, for oil, would never go above 500 litres. This will give for an average house demand of circa 50w per sqm approx 90 - 120 minutes of heat for an input of approx 45 minutes (that's from cold).
The buffer tank is our source of modulation. If we can ever get a modulating oil boiler, we won't need a buffer with an oil boiler. Until then, a buffer makes for very low wastage of our boiler runtime & no over-firing, for example, OP's existing demand for UFH is 232sqm x 50 watts = 11.6kw. System losses will be minimal as they are lost to the floor so it's only pipework to manifolds. C26 will most likely be firing at factory setting of 23kw. Double the required, so will be short cycling like mad. Answer: a buffer! Heat the buffer, draw the low demand as required. Lowest allowable temp of buffer will be 40C.

Take the HW demand directly from the boiler when required, perhaps 30 mins in the morning & 30 mins in the evening. Use the diverted valve for this.

I appreciate all the info Shane, fair play.

If i do the following:

1. Timer on the hw.
2. Replace the stats/controls

Any idea of cost? Considearing i have 8 stats to replace

shane0007 · 23-02-2014 7:43pm

pat35 wrote: »

Shane, The oil the boiler is heating the HW cylinder 24/7 to say 60 degrees is there any savings by having the solar at all.If even having time clock/controls for HW could there be a saving of upto 300 euro+ pa?

Not in the winter but I would doubt very much the OP has the UFH on during the summer & is most likely getting close to their requirements on decent summer days by solar & just topping up when required.

shane0007 · 23-02-2014 8:12pm

Ah Here wrote: »

I appreciate all the info Shane, fair play.

If i do the following:

1. Timer on the hw.
2. Replace the stats/controls

Any idea of cost? Considearing i have 8 stats to replace

I'm not saying that. I am only giving you pointers trying to guide you in the right direction. A survey of the system could well reveal other issues or confirm my suggestions.
Cost wise would depend on whether your existing wiring to the stats can be re-used. Generally it is Cat5e screened but can be mains also. Heatmiser do a few to suit the various requirements. A UH1 control centre would be also required.
I would also include upstairs as your system was designed to heat both & should easily heat both economically if the changes I suggested solved the problem.
Upstairs with easiscreed would only need to on for limited periods but definitely worth while.

Ah Here · 23-02-2014 8:41pm

It looks like mains wiring. Ill see if heatmiser have a rep who could have a look

shane0007 · 23-02-2014 10:25pm

Ah Here wrote: »

It looks like mains wiring. Ill see if heatmiser have a rep who could have a look

They also do mains units but it will depend on how many cores you have available. If you are struggling on the number of cores, they do a battery one that will just require the switching circuit cores.

Their technical department is in the UK, but you can call them on 01-4852893. This will divert to UK with them paying the divert international rate.

Before you go down the route of replacing units, you really need to get a survey by somebody who knows what they are looking at, preferably from somebody that is not sales orientated.

Irish Steve · 23-02-2014 10:45pm

Can I throw in a couple of thoughts.

The only mention of insulation was in the first post, "well insulated", which could mean anything, given the way things are with insulators and what was regarded as well insulated 10 years ago means very little now with the way the standards have been changed.

Are the walls cavity or solid, if they are cavity, are the cavities insulated, or filled, or has anything been done in that area.?

What depth of insulation is in place in the ceilings? Is the upper floor across all the lower floors, or are we talking dormer here, so some ceiling area above the ground floor is not covered by upper floor.?

Has any checking been done on how airtight the house is, to try to determine how much heat is being blown out by draughts?

How well insulated is the hot water tank, given it's being heated 24/7. ?

Reason I ask is that we're in a 3000 Sq Ft Dormer bungalow 2000 lower, 1000 upper floors that was built in the early 90's, and it was horrendously expensive to heat (traditional radiators on a 120,000 Bthu Sime oil boiler. ) What has made a significant difference is that the cavities were filled last summer, and we've noticed a difference with just that done.

There's still a job to do to reduce the airflow up one of the chimneys, which is not as simple as sticking a balloon in it, as it's above a gas fire, which was put in to cover emergencies ( I will never be single fuel again, having been caught by rota power cuts in the UK in the 80's, even the oil system needs electricity, although I do now have a generator for that, it came to support a computer after we'd moved in), and I need to do a major job to reduce the wind effect through the roof, the other issue being no insulation under the dormer floor, so a huge potential heat loss there that was only partly blocked with polystyrene blocks in the joists to block the airflow, once I'd found the problem the first winter here.

I guess what I'm getting at is that if the heating is costing €2500 to run, a significant portion of the heat is going somewhere that it shouldn't be going, and changing to radiators won't necessarily solve the problems of heat loss, they will just change how the heat is delivered into the rooms that are losing it.

Shane's comments about boiler servicing are relevant, I've just had mine done recently, having not had it checked for a while, and that has also helped.

UFH is best suited to a house that's being actively used for long periods of the day, in that it's providing a reservoir of heat in the floor that's being held at a reasonably static temperature, and changing the temperature of the floor slab doesn't happen quickly, whereas radiators will pull a room air temperature up quickly, though getting the fabric of the building up to temperature still takes time. If the air is warm, the occupants feel warm, even if the fabric of the building is still coming up to temperature, so if there are periods of non occupancy, then UFH may well not be the most economic solution to heating the house.

Heating the hot water 24/7 is probably costing you money, unless there's a houseful of people taking showers at all sorts of strange times, most of the time, we need 2 periods of under 1 hour per day to ensure sufficient hot water for pretty much most situations, unless we have visitors, and even then, a 1 hour boost is plenty to cover what's needed.

Hopefully some food for thought.

Ah Here · 24-02-2014 10:06am

Thanks for your input Steve,

I built the house myself with direct labour so I was sure the house was well insulated - 100mm under the subfloor, 50mm kinspan in the walls, insulated slab and regular insulating in the roof of upstairs, insulation in the ceilings and under the upstairs floor, with triple glazed windows throughout. My windows were put in by munster joinery and the two bathroom windows are a disaster, but I'll be getting them fixed soon.

I'm tending to agree about the hot water. We use it for baths/showers in the evening and for the washup, so it is really used only from say 5-9pm. the solar panel should heat it sufficiently during the day for all other needs. Some people say that it is more economical to heat it 24/7 instead of heating it up for a few hours and letting it cool again, but I have my doubts (although i am no expert) that it is very economical to be heating the water in the middle of the night for no reason.

Does the heating of the water for the HW affect the heating of the water for the UFH (excuse my ignorance!).

MicktheMan · 24-02-2014 10:44am

Ah Here wrote: »

Thanks for your input Steve,

I built the house myself with direct labour so I was sure the house was well insulated - 100mm under the subfloor, 50mm kinspan in the walls, insulated slab and regular insulating in the roof of upstairs, insulation in the ceilings and under the upstairs floor, with triple glazed windows throughout. My windows were put in by munster joinery and the two bathroom windows are a disaster, but I'll be getting them fixed soon.

I have to agree with Irish Steve.
OP, in your post I've quoted above, there is no mention of air tightness measures. Now, while insulation is important, air tightness is just, if not more, as important as insulation. Especially in our mild but windy climate.

From experience of testing houses for heat loss, dormers are the worst (by far) for air leakage issues.

Perhaps you should consider having the house tested for heat loss mechanisms first because if, for example, the house is leaking like a sieve, then, no amount of tinkering of the heating system will be of much help.

Ah Here · 24-02-2014 10:50am

MicktheMan wrote: »

I have to agree with Irish Steve.
OP, in your post I've quoted above, there is no mention of air tightness measures. Now, while insulation is important, air tightness is just, if not more, as important as insulation. Especially in our mild but windy climate.

From experience of testing houses for heat loss, dormers are the worst (by far) for air leakage issues.

Perhaps you should consider having the house tested for heat loss mechanisms first because if, for example, the house is leaking like a sieve, then, no amount of tinkering of the heating system will be of much help.

Thanks Mick,

I know the bathrooms are leaking heat as the windows are a disaster, so I will rectify that. I have one of the chimneys well stuff and don't ever use it, and the other chimney has a stove which is also stuffed. I also have big windows along one side of the house. Otherwise I'm happy that it is not leaking too much heat.

changing from ufh to Rads

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