Changing whole house heating

bludger

Hi,

We have a three bedroom bungalow which is all electric. The storage radiators, which are over 20 years old, are starting to need new thermostats and control knobs, and are getting very dear to run now. Scottish power has advised me that my bill will be a lot higher next year.

So, I'd like to put in a new system. It seems the sensible options are heat pumps air to air; or a solid fuel, wood chip/pellet boiler wet radiator system.

A few considerations: we have seven rooms to heat, including kitchen and bathroom. And I think I'd need eight radiators for a wet system - the boiler could go in theflat roofed garage

I'd dearly like advice on this. In a few years we will have to downsize our place so, perhaps, we should be including the selling points of a new system in our considerations.

macman

Presumably no chance of connection to mains gas?

bludger

No, no chance of gas at all In the country here.

Been scouring the internet for info on biomass boilers and am getting disheartened by the number of problems that home owners have experienced.

Can you still get free standing anthracite boilers?

lovesgshp

bludger wrote: »

No, no chance of gas at all In the country here.

Been scouring the internet for info on biomass boilers and am getting disheartened by the number of problems that home owners have experienced.

Can you still get free standing anthracite boilers?

Why not go for a air-water heat pump. A air-air, is not going to heat your water for domestic use, so you will still need a immersion heater type system for that on top.

matelodave

we had a similar problem nearly 4 years ago when we moved into our three bedroom bungalow. We eventually chose an overlay underfloor wet system (polypipe Overlay) with a Daikin 11kw air source heatpump.


Our floor area is approx. 140sq.m, 3-beds, bathroom, hall, kitchen, dining room and lounge. It all works as it should and keeps us cosy and warm and produces all our hot water as well. Our electricity bill for last year was £880 (just under 8000kwh)

bludger

Thanks for your replies.

We are on economy seven and have a large water tank with immersion heaters. We are quite happy with that as the night electricity rate is about half the day rate and I don't suppose that a heat pump would do any better.

So, perhaps a heat pump for heating only might be the answer.

That overlay underfloor idea does seem very attractive. Is the system reasonably responsive? Can you control the on/off periods as in a gas set-up? How long does it take to warm the house up from cold?

matelodave

It takes ages to heat the house up from cold - about a day if it's stone cold. A fact we found out when we went away for a month in in December 2010 when the outside temperature stayed well below freezing all of the time - we hadn't had it long and were still learning how it works. They do not work like conventional boilers so you need to know how to use them effectively


A heat pump system should be running at somewhere between 30-40 degrees. The cooler the better. However the cooler it runs, the longer it takes to heat the house. That's where good insulation helps. The overlay system is more responsive than a buried system (which means it cools quicker as well), but heating a house from cold when the floor temp is only 30-35 degrees means it takes a lot longer than a radiator at 70 degrees to get the room up to temperature.


We are at home all day so the system water temperature idles along at anywhere between 25 and 35 degrees (outside temperature compensation) but can go up to 40 degrees when its below zero outside. The programmable room stats (one in each room) control the flow through each of the heating loops and have a night set back of 3-4 degrees so the place doesn't cool right down. In fact we set the temperatures to suit the times we expect to be using them - so the bathroom is warmer when we get up and for when we use it in the evening. Cooler during the day and set back overnight. The lounge is warmer in the evening than during the day but isn't allowed to get stone cold overnight. We get sun on the lounge, which heats it up and shuts off the floor until the room cools again.

There are several advantages of u'f systems. No radiators, so you can put your furniture where you like. Warm floors so any draughts are warmed up. Less dust as air isn't being circulated like it does with rads. The whole room is warm, not just the area near the radiator. You can also have the thermostat a couple of degrees cooler as all the room is warm it actually feels warmer

bludger

Thank you Matelodave for a very informative and considered reply. I shall get quotes for a similar system asap.

I'll let you know how we get on.

Best wishes

matelodave

If you want more info, you can pm me and I can let you have some piccies (of the u'f as well as the heatpump installation) and a tell you more about it

AdrianC

You don't have to be on mains gas to have gas - we've got gas hob and boiler fed from an LPG tank in the garden.

thenudeone

AdrianC wrote: »

You don't have to be on mains gas to have gas - we've got gas hob and boiler fed from an LPG tank in the garden.

Although bottled gas is about a third more expensive than oil, which is itself around 50% more expensive than mains gas, so definitely not a low-cost option.

I would suggest looking at heat pumps, but if you want a high temperature one, you nee to look very quickly.

Until 31st March, it is possible to install a high-temperature heat pump (i.e. one which will output water which is hot enough to heat a house using normal sized radiators, such as the Daiken Altherma HT http://www.daikin.co.uk/binaries/AlthermaHT_UKEPLEN13-724_tcm511-277337.pdf) and STILL qualify for the Renewable Heat Inititative (like a feed-in tariff) of 7.3p/kwh once it's introduced in April. The RHI could be substantial and could easily cover the heat pump installation cost over its 7 year life (depending on your property). Normal sized radiators will make the house more saleable, IMO.

Heat pumps installed after 1st April and operating at over 53C will not be eligible for RHI. To get RHI, you would have to have a lower temperature heat pump and would probably need to replace all the radiators to work on lower temperature heating water.

Have a look here https://www.gov.uk/government/consultations/renewable-heat-incentive-proposals-for-a-domestic-scheme