HELP Needed for Underfloor Heating

YorkshirePete

My wife and I have just moved into a flat, and we have underfloor electric heating, but no instructions on how to use it. From what I know we have

1) Economy 7 Electric Supply
2) PACTROL Weather Watch Unit
3) A 24 Hour Timer
4) A Boost switch
5) Room Thermostats

As its going to start getting cold soon, I could do with knowing how to use the system and how long I should leave it on for. Basically how each of the items work together

Your help would be appreciated

Many thanks

Euphoria1z

1-if your going to use at least 40% of your energy during the night then consider a day/night E7 tariff where the night rate is a lot cheaper than the day, thus if you have storage heaters, you use the cheaper rate at night to build up heat and release during the day. otherwise have a normal tariff where the rates are the same.


2-no idea, sorry.


3- use the timer to set the heating/hot water if applicable, to come on at a certain time, i.e. an hour before you wake up or come home etc.


4- booster switch. best not to use it, costs a lot of money in price per unit, its there for emergencies when you really need the instant heat


5-adjust accordingly for each room depending on how hot you want each room.

YorkshirePete

Cheers

We do have a day/night tariff. Which is useful as the water heater has a separate timer and runs during the cheap night time tariff

I think the PACTROL Weather Watch increases the amount of heat released when its really cold outside...but Im not sure, this is the bit im more interested in

I think I need to set the timer to come on during the night or as you say a an hour or so before we get up, I leave the boost alone

Cardew

Largely it will be a case of 'suck it and see' depending on your lifestyle -e.g. out all dat or home all day. If you are a working couple, your weekend needs will be different to weekdays.

This explains the Pactrol weather watch.

http://www.pactrol.com/pdfs/Pactrol_weather_watcher.pdf

The first thing I would do is make sure you have the cheapest Economy 7 tariff available; the disparity in prices between the various E7 tariffs is huge.

CashStrapped

Sorry if I have missed something....but your current heating set-up seems to be unsuitable for an E7 set-up.

At the moment I assume the hot water storage tank makes use of E7 (you suggest this in your post).

For space heating E7 is designed specifically for stored heating solutions such as ....storage heaters.

Underfloor heating will use the extortionate day rate of any e7 tariff. It cannot store heat on the night rate.

So you have two choices.

1) Switch to the most competitive standard tariff, which may indeed be a lot cheaper.

2) Install storage heaters and stop using the underfloor heating.

For e7 to work you need to get your night usage percentage as high as possible. Minimum would be around 55%. It should be easy to get it much higher (although it does depend son living habits).

As only your hot water (I assume) is using e7, then you may find this very difficult, hence a standard tariff may be better.

Try to work out your annual KWH use, night use percentage and do a comparison for both E7 and Standard tariffs.

The weather watch is just like an automated thermostat. So rather then you setting the desired temperature on a given day. The unit should do it automatically for you.

I strongly suspect getting off e7 will be the best solution.

As Cardew points out, if you are out most of the day and hardly use the underfloor heating, then it may be OK. But you need to do the maths and comparisons.

Edit: A closer look at that weather watch link, it seems this may be left in from when the flat had (in the past) storage heaters. It seems designed to work with stored heat solutions, not underfloor heating. Hence why you also have thermostats in each room.

YorkshirePete

We are in a rented flat so would need to get landlord to install storage heaters. I guess as we are out most of the day and would only need heating for a few hours when we get home and on a morning, then we will benefit from E7 rate during the early morning, but get penalised during the early evening

I guess I can live with that as our tariff isnt that bad.

I was more after why I have the pactrol, timer and booster

CashStrapped

As I said, I would guess the pactrol thing is a remnant of the older system as I can see no use in the current set-up.

I would still do a comparison and check your current tariff against others in the market.

What figures are you using for comparison.

I would take daily readings (at the same time each day) for a week. Then do the same when you start using the heating.

You can then extrapolate your annual KWH use and your day night split.

I just calculated (for my area) that a standard tariff would be cheaper than an E7 tariff with only 30% night use (assuming a total annual use of 5000KWH, (which is probably lowish use for a E7 property)

So it pays to work out your annual KWH use and do an accurate comparison.

Cardew

YorkshirePete wrote: »

I guess I can live with that as our tariff isnt that bad.

Can you state what you are paying for peak, off-peak and Daily standing charge.

greenbee

If the underfloor heating is very old it may work on the same principles as storage heating. My grandparents had this in the 80s - the ground floor was essentially a massive storage heater (divided into zones by room). It was very warm... And probably very expensive to run even on E7.

If you're on the ground floor you may have this system. If you're not on the ground floor it's unlikely.

Cardew

I have also assumed that it is electrical underfloor resistive heating i.e. an electrically heated rubber 'mat'.

It could of course be water filled pipes from a large heat store(water tank).

MiserlyMartin

Underfloor heating seems to be sold as the next great modern brilliant thing in heating. I know people who rave about it. I'm not convinced. Surely it is expensive because its electric not gas powered and not efficient because a proportion of heat will be lost through the floor to earth?