TNG Services completed the replacement of an existing Vaillant ecoTEC Plus 830 combi boiler with a new Vaillant ecoTEC Plus 840. The upgrade was selected to provide increased domestic hot-water capacity while retaining the space-saving advantages of a combination boiler.
Why replace the Vaillant 830 with an 840?
A combination boiler heats water directly from the mains whenever a hot tap is opened. This removes the need for a separate hot-water cylinder, but the amount of hot water available at any one time is governed by the boiler’s output together with the pressure and flow rate of the incoming mains supply.
Moving from the Vaillant 830 to the Vaillant 840 provides greater hot-water capability. This can be useful in properties with higher demand, particularly where occupants want improved performance when more than one outlet may be used.
Important: installing a higher-capacity combi boiler does not by itself guarantee full simultaneous bath and shower performance. The incoming mains water pressure and flow rate must also be sufficient, and the combined demand must remain within the boiler’s available hot-water capacity.
The existing Vaillant ecoTEC Plus 830
The original Vaillant 830 was installed within a fitted cupboard. Before removal, the surrounding pipework, flue arrangement, gas supply, condensate route and electrical connection needed to be considered so that the replacement boiler could be installed safely within the existing space.
Removing the old boiler and preparing the installation area
Once the existing appliance was isolated and removed, the installation area and existing services were accessible for inspection and preparation. Boiler replacement work is not simply a matter of hanging a new appliance in the same position: the connections and surrounding installation must be checked for suitability and adapted where required.
- Removal of the existing Vaillant ecoTEC Plus 830.
- Assessment and preparation of the existing boiler position.
- Adaptation of the connections to suit the replacement appliance.
- Installation of the new Vaillant ecoTEC Plus 840 within the available cupboard space.
- Final operational and safety checks following installation.
New Vaillant ecoTEC Plus 840 installed
The new Vaillant ecoTEC Plus 840 was installed in the existing cupboard position and connected to the property’s heating and hot-water system. The finished replacement provides increased hot-water capacity while maintaining a compact installation.
Can a Vaillant 840 supply a bath and shower simultaneously?
Potentially, but performance depends on the complete water-supply system rather than the boiler model alone. The property must have adequate incoming mains pressure and flow, and the combined demand from the bath, shower and any other open outlets must remain within the boiler’s hot-water capability.
That is why water pressure and flow should be assessed before recommending a combi-boiler upgrade for simultaneous outlet use. If the incoming supply cannot deliver enough water, fitting a larger boiler will not create additional mains flow.
Professional Vaillant boiler replacement
TNG Services provides professional Vaillant boiler installation, servicing and repairs in Stevenage, Hertfordshire and North London. We assess the existing installation, the property’s heating requirements and the expected hot-water demand before recommending an appropriate replacement.
Considering a Vaillant boiler upgrade?
Contact TNG Services to discuss replacement of an existing combi boiler and whether a higher-capacity model is suitable for your property and incoming water supply.
Request a free quote