Our customer had already fitted a Hot Water & Central Heating installed Hometronic system in his main residence, complete with an accumulator boosted hot and cold water system.

He has a beautiful wooden barn building, separate from the house, which he uses to work from home.

We discussed using a combination boiler and radiators, but the sloping eaves design of the barn and the various space constraints within meant that radiators would not be ideal.

The barn, having a roof room with a vaulted ceiling, gets very warm in the summer, so we recommended fitting a heat pump.

Historically, a heat pump has two speeds, on and off, which for a heating appliance is uneconomic, because the task is never quite the same every day (British weather being what it is!).

The Worcester Bosch air/air heat pump is the latest modulating design, manufactured by Bosch subsidiary IVT.   This means it can deliver a higher level of efficiency than earlier units.

The Worcester Bosch heatpump has two components, an internal fan assisted heating /cooling unit, which is very small,

Ground floor unit

and an outside unit containing a quiet fan.  The outside fan unit extracts latent heat from the outside air, by passing very large volumes of low temperature air across a heat exchanger.

Outside Bosch air 2 air

This low level latent heat – which can be extracted even in temperatures as low as   -12ºC – is forced through an electrically powered (variable rate) compressor and transmitted via a pair of small bore refrigerant pipes to the inside unit. 

The inside unit then gives up to 6kW of heating,

- using typically 2kW of energy you have paid for,

- and 4kW of latent heat from outside, which you have not paid for. 

In very warm weather the unit can work backwards, extracting heat from the inside unit and discharging it outside, cooling the office.

Generally speaking, electric heating is very expensive.  Conventional heaters use resistive elements (eg: night storage, electric fan heaters, immersion heaters etc) and the energy you put in, is what you get out.  So if you put in a 3kW heater, you will get 3kW of heat from it. 

The low temperature latent heat extracted from the air, once fed through the compressed and then uncompressed refrigerant, gives far more efficiency for your money.  If you put 2Kw into a Bosch air/air heatpump, you can expect to see around 6Kw output for most of the year, giving a Coefficient of Performance 0f 300%.  It sounds like an impossible ‘perpetual motion machine’, but the extra performance is coming from low temperature latent heat in the atmosphere.

Upstairs unit (grey cable is not part of our installation)

We fitted two of these units, one to each floor.  The two compact exterior units were mounted around the rear of the building, used as a garden storage area.

Our customer reports that he is very pleased with the installation, which was fitted in January 2009.

If you have a small open plan flat, conservatory or barn conversion, and would like cheap running costs comparable or less than Natural Gas fired heating, together with air cooling in the summer, this may be what you need!

As the owner of Hot Water & Central Heating, I spend much of my time visiting properties where customers want advice and costings for boiler replacements, pressurised hot and cold water systems etc.

On one sunny day in March 09, I visited a couple in Limpsfield, Oxted (Surrey) with a Glowworm Energysaver.  This boiler was significantly corroded and there was a saucer placed strategically to catch the drips.

Later on the same day I was at an address in Caterham, Surrey, at the site of a converted military barracks.  Same boiler, same problem!

This is what a Glowworm Energysaver looks like just before it hits the skip

Here are a few photographs of the Caterham unit, which we removed and changed for a Viessmann 100 Compact. 

If you have one of these, start saving up for a replacement

Unfortunately, my camera batteries were flat when we finished the work, so there are no photographs at this stage of the renewal work.

Hot Water & Central Heating have also  replaced the same boiler 2 doors away, around 18 months ago!

We have just received the go ahead to replace the unit in Oxted too; if the customer gives permission for photos, that will feature on this blog in the next 4-5 weeks (we are quite booked up at the moment).

Our customer lives in Oxted, Surrey, and had an Ideal combination boiler initially installed under the Warmfront scheme around 7 years ago.

Not uncommonly for this model, a plethora of parts had been fitted over the years to try to keep it working, but without any success.  Some of the old parts were still on site.

We recommended fitting a new Worcester Bosch Greenstar 28i Junior condensing combination boiler.

Worcester Bosch Greenstar safely installed in cupboard

This new unit easily fitted inside the old boiler cupboard, and was considerably quieter than its predecessor.

This was quite an easy job (makes a change) because all the pipework was in good order and there was a nearby drain (needed for a condensing boiler).
We ran the new condense drain in 32mm tube, as this is recommended by Worcester Bosch for outdoor applications to prevent freezing, which commonly occurs in bad weather when normal 21mm pipe is used.  If you have a Bosch boiler displaying ‘EA’ in freezing weather, you can bet it is a blocked drain……

We fitted a Bosch plume diversion kit to the flue, to direct the steam (called plume) from the low eaves area and thus preventing damage from plolonged exposure to damp.

Just inside the eaves - new flue and plume extension

As usual, the warranty was extended to 5 yrs, covering our customer for any breakdowns until 2014, using the 320 strong (at last count) Worcester service force.

Completed in early April 2009, this customer’s house, on the Sanderstead/Purley borders (Surrey, UK) had an aged Potterton boiler removed and changed for a new wall hung Worcester Bosch 24Ri.

Who left that van there?

The new boiler was a third of the size and weight of the old unit, but had exactly the same power output.

The old cast iron unit had been very reliable, but extremely wasteful of gas.  Old floorstanding cast iron units rarely give an efficiency of greater than 65%. 

A new high efficiency boiler will achieve around 90% efficiency.

In other words, comparing the old boiler to the new one, for every £1.00 you spend on gas, 25p is immediately lost, forever.

And of course, if you are using less gas, your household emissions will lower, and there will be considerably more gas left for everyone else.

Inside the utility room

The only losers are the people selling you the energy in the first place…….. 

Getting back to our installation picture file, the old boiler had an enormous balanced flue which we painstakingly bricked up to match the existing….. if you look closely you may be able to see.

Completed job, spot the brickwork remedial work

Our customer’s boiler is warranted through our preferential arrangement with Worcester Bosch, until April 2014.

Our customer owns a terraced town house in London SE19.

It was late when we finished

He had considered a solar hot water system in the loft, as he wanted to minimise his family impact on the environment;  with solar hot water it is important to maximise the hot water storage, or you quickly run out of solar heated water and have to use the boiler.

Unfortunately, the design of these properties leaves a low headroom in the loft, restricting the size of cylinder, and there is limited weight capacity for large volumes of water.

So, instead, he decided to fit the Vaillant ecoTEC+ 937 hybrid combination boiler.  The wall hung unit comprises an 837 combi with a set of hot water storage tanks built in a pod at the back.  This makes the boiler quite large and heavy (getting on for the size of a washing machine), but it delivers a superb performance of 20 litres per min for the first 200 litres of drawoff.

We fitted the new boiler on the brick gable wall and used a vertical flue system.  Five new radiators were also supplied and fitted, and we were fortunate to be able to use some existing ductwork from a warm air installation to hide most of the pipework.

New Vaillant 937 in the loft

The Vaillant 937 is a good alternative to an unvented cylinder and boiler in a medium sized house, because it takes up relatively little space.  Other similar solutions offered by Hot Water & Central Heating include the Worcester Highflow CDi range.

The house, located in Smallfield, near Gatwick, had a conventional heating system with a copper cylinder, water tank etc.  The old boiler had been mounted in a bedroom cupboard, which is always best avoided for noise reasons.

You can just see the new boiler flue on the roofline......

We fitted a new Worcester Bosch Greenstar 37CDi combination boiler in the loft space, on a custom made partition.

New 37Kw boiler mounted in loftspace

The Worcester boiler has a high hot water flow rate, which uses over 37Kw of power.  This necessitated a new gas pipe, which we connected via the existing external recessed meter housing and routed into the loft space.

We're pointing at our new gas connection

The new boiler system rendered the hot water cylinder and tanks redundant, leaving some useful space under the stairs for a cupboard.

New coats cupboard in the making (HW cylinder was located here)

Finally, we fitted the excellent Honeywell CM927 wireless thermostat unit to control the heating in the house.

Honeywell CM927 room thermostat

This house was in great internal condition with white carpets everywhere – heating installers hate white carpets!  But the owners made our chores a pleasure, even putting some of their own dust sheets down before we arrived!

Our customer lives in an area of Crystal Palace where the water supplier has in the last 12 months reduced the pressure in the mains.

The secret to successful showering is in the garage

This has resulted in a pressure just above 1bar on the lower ground floor;  this house is on 4 stories and there are bathrooms on the 2nd and 3rd floors.  The result was that the bath took ages to fill, the shower on the 3rd floor could not be used, and the shower on the 2nd floor was poor.

Protests to Thames Water from most of the residents in the immediate area did not result in satisfaction, because they were supplying over the statutory minimum pressure to the bottom floor of the property.

Hot water in these properties is supplied through a Gledhill Systemate III heatstore.

Hot Water & Central Heating were asked to provide a solution for the problem, retaining the existing boiler and heatstore.

We fitted a TCWS Charger and Mainsboost system in the lower floor garage.  This innovative patented unit consists of a pumpset and an accumulator.  The pumpset uses less than 12 litres per minute and incorporates anti backflow protection, enabling it to be connected directly to the water main.

TCWS Charger and Mainsboost in garage

It is very quiet in operation, and charges a large accumulator on a ‘trickle’ basis to replicate the performance of an accumulator on a 3bar main.

The Pump incorporates programming to manage the duty cycle and the maximum/minimum pressure.  Once commissioned, the system needs no further adjustment and will continue to run in a power cut.  If the pumpset fails, an automated bypass allows the mains to still enter the property without user intervention.

If you have a water supply problem, and are in our area (see our main ‘areas covered’ button at the top of the page) we can advise you.

Following commissioning, our customer was very happy with the results, which now means that all bathrooms are fully back in operation.  We have already been asked to provide two other nearby households with quotations for similar systems.

Stop Press:  Following the success of this installation, Hot Water & Central Heating have received an order to install an identical system to the house next door in May 2009.

We spent 3 days in this loft

Our customer in Purley had a boiler fitted by Hot Water & Central Heating in 2005, and was in the process of having a bathroom refitted. 

Vaillant ecoTEC installed in 2005 - as good as new

Their old gravity water system cylinder was in the way of a new shower enclosure.

Old gravity cylinder - recycling beckons

We worked alongside their bathroom installers (Visions) to swap over from a vented bathroom setup to a new unvented cylinder in the loft. 

Tim holding up the uniSTOR 260

Our customer is a retired chemical engineer, and he specified one of the first Vaillant weather compensated heating systems when we originally installed his Vaillant ecoTEC 630 boiler in 2005.

Naturally, he decided to go for a Vaillant unvented cylinder, in this case the uniSTOR 260.  He now has what Vaillant describe a ‘total system solution’.  This is where the boiler controls know the precise hot water temperature in the cylinder, and modulate the boiler output according to the scale of the task. 

In a Vaillant total system solution there is no separate timer and programmer, all the heating and hot water is controlled from a single wall mounted controller.  We had fitted a Vaillant VRC400 back in 2005, but recently this has been superceded by the new VRC430, and as this was an inexpensive upgrade, our customer chose to have the newer model fitted at the same time.

Latest Vaillant controller was installed

The uniSTOR was sited in the loft space, involving a considerable amount of pipework and subsequent lagging.

There was a surprising amount of pipework in this job

We also upgraded the water supply from the garage, to give the best possible performance at the taps.

New water pipe (insulated) in garage on its way to the loft

Connected to a suitable water supply, unvented hot and cold water systems give a performance level similar to that obtained from a shower pump without the noise and unreliability associated with the latter.

Finished job

They have to be installed by a qualified installer and the safety devices suitably installed;  in our case, we ran the emergency discharge pipe in 28mm copper in a discrete corner of the property, rather than using the nearer back of the house, which would have been unsightly.

Discharge pipe was run at side of house

There was a time when a backboiler (a gas fire with a hidden cast iron central heating boiler hidden inside the fireplace) was the height of fashion.

Unfortunately, the front fires now look dated, but more importantly, the bit at the back is usually only 60%-65% efficient in its use of your expensive gas.

Our customer in Pembury (near Tunbridge Wells, Kent) had decided it was time to invest in a new energy efficient boiler, and from the 3 quotes, he chose Hot Water & Central Heating for the task.

The boiler was to be moved from the lounge to a utility room area, in the process of being refurbished.

We suggested the Worcester Bosch 18Ri conventional boiler, which has an efficiency of over 90%, and comes with a full 5 year warranty when fitted by Hot Water & Central Heating.

The new boiler

The Worcester 18Ri has a depth of only 280mm, meaning that it will fit in a standard wall cupboard – which is handy, because our customer will be having new units on this wall.   The boiler will be completely hidden when renovations are completed.

In this case, we were fortunate to have the boiler on an outside wall, which made fitting so much simpler.

New boiler location, from the outside, showing neat flue outlet

The house, located in leafy Caterham, Surrey, was built in the early 60s and was heated by a warm air ducted system.  In common with many installations of this period, some rooms had no direct ducting and relied on leaving the doors open. 

The subject of this post

Our customer wished to use the large cupboard currently occupied by the warm air system for storage.  They also wanted a mains pressure delivery of hot and cold water, and minimum wastful stored hot water.

Warm air cupboard after removal of old heater, new pipes shown

We suggested the new Worcester Bosch Highflow 440CDi.  This is a floor mounted unit, recently updated from the Highflow 440.  With identical dimensions to a washing machine, the new Highflow has a new control panel and has more flexible flue outlet arrangements.

Worcester Bosch Highflow 440CDi - nearly completed

The Highflow 440 incorporates a small internal unvented store of hot water, which enables it to deliver up to 20 litres of hot water a minute.  Being able to be sited under a worktop, it is a very neat space efficient solution.

Finished!

It is always difficult fitting radiators in a property formerly fitted with warm air, because there are pipes to run.  In this property there was a solid ground floor, but we found ways to minimise the visual impact of pipe runs.

Vogel & Noot Vienna Line radiator

Our customer agreed to specify our preferred Vogel and Noot radiators, which have a modern neat panelled appearance.  The single panel versions fit very close to the wall indeed, minimising visual impact in the room.  Honeywell radiator valves were used throughout, as usual.

Pipework can often be hidden on the other side of the wall

The new Highflow 440 CDi can be used with the Worcester outside plume management kit, which we fitted to take the flue output to a satisfactory high level discharge point, where it was unlikely to be a nuisance.

The new plume management kit now available on the 440CDi comes in useful here! That's a lot of steam.

The hot water cylinder and water tanks were removed, the Worcester Highflow now manages the supply of heating and hot water for the entire property singlehanded.

As a Worcester A+ installer, our customer enjoys a 5 year parts and labour warranty on his new boiler.  Our experience with previous Worcester Highflow models suggests he is unlikely to need it, but nevertheless it is covered until 2014!