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CENTRAL HEATING INSTALLATION This is our core business; from the smallest combination boiler to the largest domestic system. We also maintain industrial sized systems, so there is little we haven't had experience of over the years. Please see below for details about different types of boiler, condensing technology, and warm air central heating.

If you like would a free site visit and application advice, please call us on:

Domestic Gas Central Heating:
On most domestic gas Central Heating boilers fitted by HWCH you are given a
5 year parts and labour warranty
All we ask is that you have the boiler serviced annually, in line with good practice.

We install Vaillant, Viessmann, Worcester-Bosch , Broag-Remeha, Buderus and Kidd products for their reliability and technical excellence. We fit combination and conventional boilers, in condensing high efficiency derivatives.

ABOUT BOILERS, THE BASICS

Conventional versus combination boilers - the pros and cons:


A Conventional boiler is purely a heater - there has to be an external hot water cylinder, control valves and radiators.

Why would you want one?

- More than one hot water outlet can be supplied simultaneously (dependant on the cylinder used)
- You have a larger house and need a boiler larger than 130,000 BTu
- You desire a longer service life for a boiler than 10-12 years.
- You would prefer to have a stored water supply in the house
- You may have recently invested in a new hot water cylinder/tanks
- You want an electrical immersion heater as hot water backup for boiler failure
- The water flow rate (sometimes erroneously described as pressure by plumbers) is too low for a combination boiler (but see low water mains pressure solutions)
- Perceived reliability advantage.


A Combination boiler contains all the necessary controls and equipment to provide instantaneous hot water and also central heating - apart from radiators and pipe, everything else is in the boiler.

Why would you want one?

- Convenience. Hot water is always available, 24 hours a day
- Economy. Only heat the hot water you use.
- Consecutive hot water demands can be made without running out
- You do not require to run two hot water taps simultaneously
- No water tanks in the roof or hot water cylinders are required.
- It's a one box compact solution, ideal for small properties
- It offers mains pressure showering without an electric pump (ideal for flats)

A note about reliability:

Combination boilers are considered by some to be less reliable than Conventional units.

It's important to remember that the combination boiler does the equivalent of a standard system, but in one box. It removes the need for external;

Central Heating Pump
Cylinder
Water tanks (both)
Motorised Valves
Hot water thermostat

All of which would otherwise be needed (and occasionally repaired) in a conventional system. Providing the system is well dosed with corrosion inhibitor (because the internal workings of combis are particularly susceptible to sludge) there should be no discernable difference in reliability.

Condensing (High efficiency) - what you need to Know

Condensing High Efficiency Boilers - an explanation:

Older boilers emit flue cases which are very hot (in excess of 160 degrees). This is rather wasteful because most homeowners purchase a boiler to heat their house, rather than the surrounding countryside. With older boilers between 20-35% of every £1.00 spent on gas goes out as heat into the garden.

For some years, high efficiency boilers have been available for industrial and large domestic systems, but their use has not been widely publicised. These units recirculate their hot exhaust gases until more useful heat has been extracted into the boiler, before expelling a much cooler exhaust. The cooler exhaust contains particles of water, (or condensate, as it is described in the trade) which create a visible 'steam like' plume.

Boilers which recycle some of the otherwise wasted flue heat are therefore called 'condensing'.  All boilers described in the UK as 'high efficiency' can be assumed to be condensing boilers. 

Condensing boilers are available for Gas, LPG and Oil fuel types.

Government Intervention:

UK Government has signed an international agreement (Kyoto Agreement) committing us all to reducing energy losses. As a result, from 2005, It became mandatory for UK homeowners to install high efficiency 'condensing boilers' when fitting a new gas unit. Oil boilers were subject to this ruling later in 2007. See 'exceptions' below.

The Government class these units as having an efficiency of SEDBUK of grade 'A', which is top marks in laymans terms (see www.SEDBUK.org for more information).

Condensing boiler reliability:

Unfortunately, over the last 8 years certain domestic boiler manufacturers may have exhibited undue haste in releasing their condensing boilers onto the market, before they had been fully tested. There have been some expensive failures, and it is regrettably not uncommon to have to scrap a condensing boiler but a few years old.

Whilst they are undoubtedly more complex, there is no reason why a quality condensing boiler should be any less reliable than a standard unit. The key is to buy from a volume manufacturer with a large Research & Development budget and a good reliability track record; which brings us back to Vaillant , Worcester Bosch, Viessmann , Broag-Remeha, Grant. For those of you lucky enough to own larger properties we suggest you may also wish to have a look at our Archie Kidd page.

Exceptions to the 'condensing only' Building Regulations:

Many of our European cousins have been successfully running condensing boilers for years. However, European installations tend to use 'vertical flues' where they protrude through the roof. The condense pluming is therefore far less visible and irritating than in the typical UK installations, which tend to use horizontal flues (ie: wall mounted).

It is recognised that there will be situations, particularly in high density housing, where the condense plume from a horizontal flue will be unacceptable to residents.

Therefore, there are exceptions to the Government mandate, some existing non-condensing boilers will continue in production to cater for this market.  Over the past few years we have found very few homes that could be classed as exempt, although some high rise modern dwellings could qualify.

We can't see why anyone would want to use more fuel than necessary and achieve an exemption.  However, those who don't want a condenser may be interested to know that a range cooker with an internal boiler is exempt.  Even if the boiler is totally separate from the cooker;  it just has to be within the same casing, such as our Heritage Cookers (see menu top of page).

Our advice:

Finally, if you want reliability, specify a good boiler, whatever your preferred
choice of system, rather than a budget unit.

We only fit the former!

Condensing technology, more background:

The high efficiency boiler was introduced in the UK by Archie Kidd. Whilst today's media suggest the idea is the latest thing, you could have bought a condensing boiler from Mr Kidd in 1982, and chances are you'd still be using it now.

Today's condensing boilers work on a similar principle of transferring as much heat from the fuel being burnt, to the water in your pipes. The last 10% of usable boiler efficiency requires the (gas or oil) fuel's internal water content to condense inside the boiler, against the water jacket. The 'latent heat of evaporation' gives away more energy when the water in the fuel is encouraged to turn from a gaseous to liquid form.

With all the extra efficiency the flue gases emitted from the boiler to outside are of a much lower temperature; this way your boiler wastes less valuable fuel heating the garden. A disadvantage is your flue tends to look a bit like a steam train’s funnel in winter.

There’s been a lot of negative publicity in the press about condensing boilers. It’s true that a significant number of boilers from 2000 onwards – culprits being predominantly British and Italian manufacturers - have already been scrapped by their owners.

Some manufacturers fretted about being left behind, desperately rushed through models which had not been comprehensively tested or funded - these boilers are the ones you have read negative comments about.

The condense in a high efficiency boiler is designed to be safely led away to the drain. The trouble is, there is a weak mix of acid present in the water condense, which will rot copper, steel, iron and even some plastics with a vengeance. Consequently, modern condensing boilers tend to be made of expensive metals and alloys like stainless steel and aluminium, which can tolerate the harsh conditions better.

The good news is manufacturers are getting better at designing out the weaknesses. Some of the German manufacturers have been making condensing products for over 10 years.

If you really don’t want a condensing boiler, you could fit a range cooker with a boiler in it –they’re exempt from the regulations. See our Heritage Range page.

Solar

Solar hot water heating:

We are solar heating installers. You could get free water heating for life!

However, to give a balance to the above statement, many householder do not appreciate that hot water accounts for only a very small amount of their gas or oil bill.   Typically only 15%;  most of your gas bill (85%) goes on space heating, which is not addressed by most solar systems.

It typically therefore takes at least 10 years to recoup its’ investment – longer than we statistically stay in one house.  We reckon payback occurs somewhere between 25 and 50 years, assuming nothing goes wrong in the meantime.  

If you have a swimming pool it does start to make sense though. 

We'd suggest you look at Heat pumps and Hometronic before investing in Solar hot water.

Powerflush:

We always Powerflush an existing radiator system before replacing the boiler. This ensures a long and reliable service life, and helps return the system to original condition.

We use the industry leading Norstrom Powerflush units, which are designed to have a high flow rate into the radiators.

Warm Air

Warm Air Central Heating:

It's not widely appreciated, but Gas Warm Air Systems are amongst the most efficient forms of heating available.

Their heating output is nearly instantaneous, and there are none of the water leaks, sticking valves, sludge, pumps, etc. than can develop with ordinary systems. As a result Warm Air installations typically have a longer service life than water based systems. There are many householders who are committed advocates of this method of central heating across the UK.

The latest Warm Air boilers incorporate significant technical advances over their forebears. On current models, instead of the basic on/off nature of old Warm Air heating systems, there are electronically controlled fan speeds and temperature regulation, making the action of the boiler much more subtle. These improvements offer significant comfort and economic benefits to the homeowner when upgrading.

New and Replacement warm Air Units:

If you have an elderly Warm Air system, we can install a modern replacement at a modest cost, incorporating the advanced new features, with minimal disruption to your property. A water heater can be contained within the casing of most Warm Air units, this will work in conjunction with a water storage cylinder. Like ordinary Gas Central Heating, an immersion heater can be fitted for backup.

We recommend Johnson and Starley, www.johnsonandstarley.co.uk warm air boilers. Based in Northampton, they supply all our new units and are the UK market leader. Our engineers have attended courses at the manufacturer's training centre.



Repairs and Servicing:

We will also be pleased to service or repair your Gas Warm Air Heating. We have considerable experience in this area. Please note that some manufacturers of Warm Air systems from the 70s and 80s are no longer trading and therefore certain parts are no longer available.
We would be happy to advise you, if you are in our service area.

Radiators and Underfloor Heating:

Go to our Radiators and Underfloor heating page.