BOILERS
Q1. What are the minimum clearances required around the boiler?
Combis (800 series) – Side: 5mm, Below: 180mm,
Above: 165mm (when using 100mm flue ) or /246mm (when using 125mm flue).
System (600 series) – Side: 5mm, Below: 180mm,
Above: 165mm (when using 100mm flue ) or /246mm (when using 125mm flue).
Open vent (400 series) – Side: 5mm, Below: 200mm, Above: 150mm
Exclusive – Side: 5mm, Below: 145mm,
Above: 165mm (when using 100mm flue ) or /246mm (when using 125mm flue).
Q2. What are the reduced flue distances required for the VTK flue terminal?
When a VTK is fitted to a horizontal flue, the clearances for the air inlet are reduced to 50mm from an opening such as a window and 25mm from an opening such as an airbrick. The terminal clearances for the ‘new’ flue outlet at the end of the VTK remain unchanged.
Q3. What is the required slope back to the boiler for flue extensions?
Where flue extensions are to be used they must be installed with a slope of 3 deg, 50mm +/- 20mm rise per meter length.
Q4. What are the minimum and maximum flue lengths?
There are many variables please refer to the air flue duct instructions.
Q5. How do you prevent the condensate from freezing?
The condensate pipe from the boiler must have a continuous fall and preferably terminate inside the building. For alternative methods see the installation manual for the product and for further information about frozen condensate please refer to http://www.vaillant.co.uk/installers/heating-solutions-1/high-efficiency-solutions-1/frozen-condensate-advice/#frozen-condensate-advice
Q6. Where should the pressure relief valve terminate?
The pressure relief valve should terminate outside the building in a safe and visible position.
Q7. What are the minimum working pressures for my boiler to operate correctly?
The minimum water pressure to gain maximum flow rate (combis only):
ecoTEC plus 824: 0.5 bar
ecoTEC plus 831: 0.75 bar
ecoTEC plus 837: 0.75 bar
The minimum gas working pressure varies per boiler so please refer to the gas pressure statement in the installation manual for your boiler.
Q8. Does my boiler have an internal by-pass?
All Vaillant boilers are fitted with a fully automatic and adjustable by-pass with the exception of the open vent boiler.
Q9. Does my boiler have Warmstart?
All current Vaillant combination boilers have Warmstart
Q10. Can I use underfloor heating with my Vaillant ecoTEC boiler?
Yes you can but this needs to have its own zone valve and temperature thermostat. You will need to wire both into the boiler.
Q11. Does my boiler require frost protection?
No - the boiler has an integral two-stage frost protection system.
However to protect cold zones within the building or exposed pipework an external frost stat may be required.
SOLAR
Q1. Can I use copper pipe to connect the panels to the pump unit?
Yes the use of copper pipe is allowed, but it must be brazed (not soldered) or jointed using compression fittings (with brass olives).
All Vaillant Solar sets are however, supplied with stainless steel piping that requires minimal joining.
Q2. Do I have to put lagging on the solar system circuit?
All pipework must be lagged with lagging that is rated for use on solar pipe work.
Q3. What is solar fluid made from?
Solar fluid is an oxygen free mix of water and (food grade) propylene glycol.
Q4. Where is the best place for the panels to be facing/placed?
The ideal orientation is south facing and at an angle of 35°- 400.
GROUND SOURCE HEAT PUMPS
Q1. Will the heat pump heat the building on a cold winter’s day?
Yes a heat pump will heat the building on a cold day. The basis for a heat pump installation should be a full heat loss calculation of the property. With this proper design, the heat pump should always be able to heat your property.
Q2. Does the heat pump provide enough domestic hot water for my requirements?
Yes, this will be part of the full heat loss calculation refered to above - please also refer to http://www.vaillant.co.uk/installers/renewable-energy-1/heat_pumps-2/ground-source-heat-pump-calculator-1 for confirmation.
Q3. Does the heat pump always require underfloor heating or can I use a radiator system?
geoTHERM heat pumps work best with an underfloor heating system but can be used with radiators provided these have been correctly sized for the system design.
Q4. Is cooling possible with the heat pump?
When combined with a correctly designed underfloor heating system the geoTHERM exclusive heat pump is able to provide passive cooling and can reduce the temperature in the house by 3 to 4 °C.
Q5. Can I use my existing domestic electrical supply?
There are geoTHERM and geoTHERM exclusive models available which are designed to run with a UK standard 230 volt, single phase electrical supply. The heat pumps have outputs of 6, 8 and 10 kW for heating and cover most domestic applications.
For larger properties 415 volts, three-phase electrical supply will be required.
Q6. I want to install a heat pump but my garden is quite small. Will this matter?
With small UK sized gardens Vertical borehole loop collectors can be used. The main constraint is access for the drilling rig which has to be considered at the design stage. Much larger gardens can of course use Horizontal collector loops which may still require access for digging equipment.
Q7. I have an existing property and I want to fit a heat pump. Will this be a problem?
geoTHERM heat pumps are designed to work in both new build and existing properties. It is essential that the heat loss requirements for your property is known so that the system can be designed to suit your property. Before a heat pump is considered it is important to ensure that the basic energy saving measures are in place such as draught proofing and loft insulation. The Energy Savings Trust provide information on ways to reduce energy usage and can also provide information on Government grants that may be available.
Q8. Are ground source heat pumps really environmentally friendly?
A ground source heat pump is an electrical appliance, using electricity to operate the compressor and pumps. For every 1kW of electricity used to operate the heat pump, up to 4.5kW of heat energy can be provided to the house for heating and hot water. A heat pump will reduce the CO2 emissions from a domestic property by up to 35 to 40%.
