Our customer has a lovely period property near Gatwick, in Sussex.  It has a very cold kitchen and lounge, and was a conventional system with water tanks in the loft and a hot water cylinder on the 1st floor.

The boiler was an old Potterton unit on the ground floor at the rear of the property.

Now, these old properties are usually a bit tight on cupboard and bathroom space, so our customer wanted to lose the water tanks and hot water cylinder, add a utility room and ideally compress all the boiler and hot water functions into a small area.

Enter the Worcester-Bosch Highflow 550 CDi.  This unit is a hybrid combination boiler, and is identical in size to a washing machine.  It has a 42kW heat engine, and an unvented water store inside.  That is the ‘hybrid’ bit, because the hot water heatstore makes this boiler deliver flow rates of hot water that could normally only be obtained from an unvented cylinder.

For the first few hundred litres of water, the blending of the preheated store and the real time efforts of the combi boiler engine deliver close to 25 litres of hot water a minute.  In real use, the unit recharges its’ heat store very quickly so rarely drops below this output.  It is a powerhouse in a small box.

We removed the old water tanks, the old cylinder on the 1st floor, and the ld boiler, and replaced it all with the Bosch unit.  This used the same flue aperture outside so did not affect the listed building requirements.

New boiler does everything for a 4 bed house

Significant modifications were made inside to the heating system, with new Vogel & Noot Vienna Line radiators throughout.  A Smiths Kickspace fan convector was installed in the kitchen, and pipewor was renewed and upsized in key areas to improve circulation through the radiators.

All pipework in the boiler area was removed from wall ducting and relocated on the ceiling to allow for some new wall openings to be created into the adjacent kitchen.

Checking the combustion settings of the new boiler

As part of a Bosch promotion for Gold Accredited Installers, our customer has the benefit of a 7 year parts and labour warranty on the boiler.

Inside a Vaillant ecoTEC + 831

We advised them to fit a new Vaillant ecoTEC+ 831 combination boiler, because it is a well built unit and reliable for a lettings customer.  All our Vaillant installations benefit from a 5 Year manufacturer parts and labour warranty.  We have fitted a few hundred of the Vaillant ecoTEC+ combi over the past five years and found it to be a reliable product.

The system was fully Powerflushed, and the new boiler fitted.  A Vaillant ‘Plume Management Kit’ was used to divert the exhaust steam to a high level outside.

Vaillant plume management - and a faulty gutter downpipe!

The old hob was replaced with a new Bosch unit, featuring an FSD.  Flame Supervision Devices are now mandatory on hobs fitted in rented properties.

New Bosch gas hob

We supplied a new Landlord Safety Certificate for the property.

Weather starting to turn

To leave the maximum room in the kitchen, we’ve suggested an external oil combination boiler.  A Worcester-Bosch external heatslave was our recommendation, it comes in an insulated and rather fetching dark green cabinet, noticeably better made than the product sold by their main competitor, with rubber seals round the doors etc.

Ricky connecting new pipework

We fitted all new copper pipework inside the house, together with our preferred Vogel & Noot radiators, which are Austrian built units with rounded corners, very child-friendly.

At one point the roads outside became impassable, so we had to halt work for three days.  As soon as the weather allowed, we were back on site, in this case this meant a Sunday.  It is pretty miserable installing an external boiler in the snow, it has to be said.

Fire valve, oil filter and oil isolation valve

We haven’t got any pictures of the finshed job, because it got dark very quickly.  But what a difference central heating makes to a house!

Like all our Worcester-Bosch installations, this boiler has a manufacturer on site warranty for 5 years, until 2016.

Old boiler location was to the right hand side of the cellar steps

The hot water cylinder was located above the cellar on a raised floor, which would have been the first landing of the stairs in the Victorian property’s original layout.

Old hot water cylinder location, floor to be lowered to make new bathroom

Sited in Caterham, Surrey, it would be fair to say that the heating system had been bodged up by the previous owner, along with the electrical work.  Various leaking parts had seen the attention of a silicon mastic gun, including radiator valves.

Our customer rather liked the idea of fitting a new bathroom in the area previously occupied by the hot water cylinder, and this meant lowering the floor, which from our perspective meant;

- a combination boiler

- relocation into the cellar for all the boiler plant

The problem with locating the boiler in the cellar is getting the flue out, and dealing with the boiler expansion relief and condensate water.  There is a boiler available in the UK which has some very flexible flue arrangements which would seem ideal for this application called a Keston, but for reasons we’d rather not go into in this public forum, they are never specified by ‘Hot Water & Central Heating’.

We fitted a Vaillant ecoTEC 837 in the cellar, and used a void area to run the flue to a suitable height for a horizontal discharge.  Gas Safe Register are quite rightly insisting that flues in voids must be able to be visually inspected and suitable arrangements are in place.

New boiler and high temperature lift pump below

The condensate and high temperature emergency discharge from the boiler were handled by a new condensate lifter product specially designed to accept high temperature water, this is unique we believe.  We no longer fit the Vaillant branded condensate lifter because Vaillant UK exclude it from their extended boiler warranty.

A Mainsboost GC450 accumulator was also fitted in the cellar to boost the water flow rate and separate the water supply, as the other 5 flats in the building cause water starvation issues as they are all fed from the same rusty water main around 200 metres long.  The water main here was delivering a very high static pressure, peaks of around 7bar were measured.  A pressure reducing valve was fitted to protect the appliances and provide a uniform performance via the acumulator.

The boiler exhaust was fitted with a Vaillant plume management kit, in white to match the building, as cars often part in the vicinity of the flue outlet, and the mildly acidic condensation could cause damage to paintwork.

New Vaillant boiler flue (in white)

Let the work commence

Now theres’s nothing wrong with warm air heating, and we fit the latest US Lennox condensing units for the more discerning customers.  But in common with many properties of this era, economies had been made with the ductwork, resulting in no direct heating of the third bedroom or bathroom.

Our customer had recently bought the property, and faced the choice of many similar households wondering whether to replace the warm air based boiler for a new one or pull it all out and put in a ‘wet’ radiator system.  It wasn’t practical to extend the warm air ductwork into the unheated area, so we suggested fitting a Vaillant ecoTEC+ 837 combination boiler in the front of the garage.

Nearly finished

We managed to utilise some of the old ducts in the property to conceal the new heating pipework, and lifting flooring elsewhere, resulting in a very neatly finished installation.

New radiator in the kitchen

Pipework detail

The relocation of the heating system meant that a very large cupboard was released in the kitchen, which is never a bad thing!

Insulated pipework inside garage

Our customer was very pleased with the results;

“I just wanted to say a big thank you to Simon and Hot Water Central Heating.  We are very

pleased with the work that’s been carried out – apart from the

radiators (we didn’t have them before) you’d never know the guys had

been here.

Sadly, we’re looking forward to it getting cold so we can test it out.

Happily recommed you to anyone.”

They wished to remove a couple of shower pumps and the water tanks and install a direct fed pressurized water system.  The problem was that the water flow rate into the property was around 9-10 litres per minute.  There was also a limited space to fit the entire boiler plant into.

It's easier to plumb the accumulator in this position

We had to boost the flow rate as well as provide the new boiler plant, all within a single cupboard.  We chose to fit a wall hung Vaillant ecoTEC 937, which is a ‘hybrid’ condensing combination boiler.  Most combination boilers heat water as you use it, but this restricts the available flow rate to around 15l/m for most units.  Hybrid combination boilers store some hotter water in preparation for usage, and then mix this with the water they ‘heat on the fly’ when a tap is opened……in the case of the Vaillant 937, this delivers the equivalent of 20 litres per minute of hot water for the first 10 minutes.

As we use hot water in bursts of activity, and then the system lies dormant, the hybrid combination boiler is a versatile solution.

But of course, we can’t get 20 litres a minute of hot water out of a water main only supplying 10 litres/min – so we also specified a Trent Clyde Mainsboost accumulator.   This stores water at pressure and enables a highly boosted flow rate when required.

Commissioning checks underway

With the accumulator, flow rates including cold and hot water of 30 litres per minute are easily achievable.

The finished hot and cold water/heating solution

We added a secondary heating expansion vessel, as the unit in the Vaillant boiler is only suitable for a modest volume of radiators.

The flue aperture was made good outside, and the decking lifted to provide a neat direct condense drain into the external drainage.

External discharge shown

As is usual with our installations, our customer has an extended Vaillant boiler warranty, from 2 years to 5 years.

The old boiler and cylinder had been squeezed into a new kitchen conversion, so it was very awkward to access the constituent parts.

Old boiler and cylinder hiding inside cupboard

We removed the old wall hung boiler and cylinder, and fitted a new Worcester-Bosch condensing combination boiler.  The hot water cylinder, tanks and associated controls were no longer required in the new configuration, and were scrapped.

New boiler in position

We cut a neat slot in the kitchen cabinet carcass, which allowed us to achieve the Worcester-Bosch clearances.  This was concealed when the access door is shut, making for a very neat installation.

Finished!

Like all Hot Water & Central Heating Worcester-Bosch installations, our customer benefits from a 5 year manufacturer warranty.

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.

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.

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!