Vaillant ecoFit Pure 835 (ErP) Combi Boiler

When a small combi will not keep up with the hot water, the Vaillant ecoFit Pure 835 (ErP) Combi Boiler is the next step up. It is the biggest model in the ecoFit Pure combi range, and this listing is the boiler only, so the flue and controls are chosen separately.

Is the ecoFit Pure 835 the right size?

The 835 has more hot water output than the 825, so it suits bigger houses and homes where a shower and a tap may run together. A combi still has limits, though. With two bathrooms in heavy use at once, a system boiler and cylinder may suit better. The 835 keeps the compact case, quiet running and lightweight aluminium heat exchanger of the smaller model.

Specification

• Brand: Vaillant
• Range: ecoFIT pure
• Maker code: 0010020391
• Suitable for: Natural gas combi heating and hot water in larger homes

Common Questions

Should I choose the 825 or the 835?

The 835 gives more hot water, which suits busier homes. The mains must supply enough flow, so test it before deciding.

Will a bigger combi run two showers at once?

It helps, but a combi splits its flow between outlets. With two bathrooms in regular use together, a system boiler and cylinder may be the better plan.

Does the ecoFit Pure 835 need a bigger gas pipe?

It may. The pipe from the meter must be sized for the boiler’s gas rate, and the engineer checks this during the survey.

Glasgow mains pressure and gas checks

A bigger combi only gives more hot water if the mains can supply it. Do a flow test at the kitchen tap before choosing the 835. Mains pressure varies across the city, so do not assume. Check the gas meter and supply pipe can handle the bigger boiler, as undersized gas pipe causes poor performance. Choose the flue to suit the route. Only a Gas Safe registered engineer may fit and commission it.

The Vaillant ecoFit Pure 835 (ErP) Combi Boiler and its kit versions are in our boilers section.

Plumb Parts trades from 555 South Street, Glasgow G14 0QX, Mon-Fri 8am-5pm and Sat-Sun 8am-1pm, for collection. Online orders are taken as well.

Datasheets

• Vaillant ecoFIT pure 825-835 Installation and Maintenance Instructions (PDF)