Tweaking the thermostat for maximum efficiency and savings

Kya deLongchamps says that making some small changes to the features of space and water heating can increase comfort levels and reduce energy bills within weeks. 
Tweaking the thermostat for maximum efficiency and savings

BABY it’s still cold outside, and if you’re stuck with traditional central heating with no bells, whistles or touch pads, you may be feeling the chill of poor performance and steep bills.

However, using some home heating tips can give a warmer, more economical result especially when it’s considered that 60% of the energy you use at home is dedicated to keeping you warm this time of year.

Frankly, this percentage is likely to be even greater if you are retired or working from home (for example raising young children or working remotely), or the heating system is oil fired and/or not optimised.

Making some small changes to the features of your space and water heating — and crucially your own home heating habits — can yield results in your comfort levels almost immediately, and in your energy bills in around five weeks.

Take your lead from the Sustainable Energy Authority of Ireland’s inspiring ‘5-Week-Plan’ which you can find in its entirety, including everything you need to know about economical water heating at Don’t be disheartened if funds are low — concentrate on their ‘must do’ tips.

Be more perceptive about the performance and timing of your system. Aim to heat the house to a comfortable level when you’re at home and turn it off completely when you’re in bed or not there.

Running a standard wet system constantly on low (less than 75C), without nearly zero-carbon levels of insulation in the walls, floor and roof, is a waste of time and money.

First of all, what do you expect in terms of temperature?

Walking around in shorts and t-shirts is lovely in a five star hotel, but 20C/21C is generally acceptable for everyone but the older or infirm householder. If you’re at 20C and still chilly, draughts may be the culprit rather than the ambient temperature. Adding just 1C to your thermostat will poke up the heating bills by as much as 10%. Don’t be tempted to whack up the thermostat in cold weather — the indoor temperature will be managed to the same level as on any other day.

Equally, turning it up from your normal setting to speed up the house heating on an unexpected return is pointless — it only influences the final temperature in the room.

If you don’t have contemporary heating controls (plus motorised valves separating hot water needs from the radiators, and conducting heat to independent room thermostats around the house) — your system can still be managed with the master boiler thermostat, a standard on/off timer, and independent radiator controls.

Standard on-off radiator valves are primitive at best — radiators don’t have to be fully on to convect heat into the space.

To start a simple zone controlled system, which follows your living pattern, a thermostatic radiator valve (TRV) on every radiator will allow you to finesse your heating, leaving bedrooms at an 15-18C during the day, and gifting spare rooms a few centigrade to just prevent the room from suffering condensation (presuming your trickle ventilation is in order).

Remove radiator covers if they are enclosing the TRV as they will fool it into thinking the room is warmer than it is. If you have space heaters, still consider the room or open plan area as a zone and choose a solution with thermostatic control to shut the unit down, or off, when your chosen conditions have been met.

Ensure heaters are sized to the room by checking their kW output and efficiency before purchase. Seven-day timers on boilers and heating appliances allow you to key in your personal behaviours in a standard week — for example if you are never home on Friday nights, or like to sleep in on Sundays.

There are times (and this will be weather dependent), when you can use your home’s ability as a passive heat shunt. If the conservatory or sun-room has a southerly aspect, open any adjoining doors to the next room on a sunny day to allow that free solar gain to flow. Conservatories don’t always boast the insulated envelope and heating features of the rest of the house — so close up when the sky is overcast.

Except in the most extreme winter, the heating will be off overnight. Oil and gas-fired central heating through a properly maintained radiator, is highly reactive.

Cut the start time for the system in the morning to around 30 minutes and allow the heating to cool down for about an hour before you go to bed (you won’t notice it, unless the insulation levels in the house are truly awful).

When it’s very cold, the house will in all probability take longer to heat from a cold start. Set the timer accordingly — say another 15 minutes to warm the rooms before you rise. In winter you’re unlikely to turn a boiler’s thermostat below 80C-70C, but don’t just set it to 80C and walk away.

How does the house feel during a standard day? Be proactive and shimmy it down a click if you don’t feel a perceptible change. If your central heating boiler is also heating your water, the cylinder thermostat must be set to no less than 60C-65C to kill harmful bacteria.

Storage heaters are often misunderstood by first time users. They should be gathering heat over eight hours using the economy of night rate electricity, then deliver this heat back to you (at your chosen temperature) during the following day. Ensure you are not using your storage heater as a convector heater by improperly setting the controls and utilising just the front panel.

If you do use convector heaters alone, choose products with modern ceramic panels with fully programmable controls, and wall mount them for safety. Pull furniture well forward of any radiator or panel to ensure it can pull in and release air — a warm chair back is not what we’re after.


Need a helping hand? Two grants are available through the SEAI that might just solve the problem, if not for this winter, certainly for next.

The Better Energy Homes Scheme

offers grant assistance up to amounts, calculated as about 30% of the costs (with an SEIA registered installer), for homes built before 2006 using the 2003 building regulation standards. There are reduced grant amounts for the third and fourth measures, so you can apply for help for up to four projects.

Read the guide book fully before applying, and don’t start work before approval has been granted (this can be completed and given immediately online). Ensure your contractor signs all the declaration of works forms in full as this can otherwise slow the 4-6 week process of grant payment. Grants include:

* €300 towards attic insulation

* €2,400 towards internal dry lining work (detached house)

* €4,500 for external insulation (four-bed detached house)

* €700 for a new condenser boiler and controls

* €600 for controls alone for a suitable boiler

* €50 towards obligatory BER on completion

The Better Energy Warmer Homes scheme,

(also administered by the SEAI) offers free assistance funds for energy efficiency improvements in the homes of the elderly and vulnerable, making the homes more comfortable, healthier and more cost-effective. If you are in receipt of the fuel allowance as part of the National Fuel Scheme, job seekers’ allowance for over six months and with children under seven, or family income supplement, or have tenants at risk, you can apply for works with no cost whatsoever to yourself.

* See more at SEIA under grants.

Quick insulation tips

Heating is only as good as the insulation keep it on site. If you or a vulnerable friend or neighbour is still feeling the chill, try warming up the house with these inexpensive weekend projects.

Attic insulation is costly and a major undertaking in a forest of trusses- choose your DIY or professional team carefully.

* A timer and dedicated lagging for the immersion tank should be a given (€15 to €20 for an economiser jacket). If your central heating is running through the tank (as it does in any traditional wet central heating system), it makes sense to keep it cosy and not convect unnecessary heat into the hot press. Enough heat will escape here and there to keep the area warm.

* Look for areas of visible pipe work without lagging in unheated areas, and slip on some 6.3mm to 19mm insulating sleeves. They are split conveniently down one side and easily cut to size with a kitchen scissors or craft knife. From 50c a metre.

* Exterior doors can be quietly bleeding heat even without an obvious ingress. Insulate the door with draught excluders all around and include the letterbox.

* 15% of your heat loss can be down through leaky plank floors. Seal gaps in boards and around conduit with mastic sealant and lay down heavy rugs.

* If your windows are draughty or single glazed, use draught strips. Replace old compressed insulation on opening elements. They do degrade — E- and P-shaped profiles are available from €6 to €7 for 5m. Insulated curtains and/ or blinds are also a must for poorly performing windows. Size curtains to sit generously on the window board and to reach 10cm or more all around the reveal.

* Throw back the curtains in generously glazed south-facing rooms upstairs and down when conditions allow.

* Zone controls, whether manual thermostatic radiator valves or under sophisticated digital control from a touch pad, rely for success on keeping the area closed off, in short, shut the doors. If there are obvious gaps around the frame, use a simple stick on roll of insulating tape and a bottom brush cut to size, to reduce heat exchange room to room.

* Use a pad of insulation batting or a ‘box’ to keep heat from escaping into the attic.

* Install a chimney balloon (or a football at the push), in unused fireplaces to prevent heat escapes. From €26.99 at Woodies DIY.

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