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Cutting costs means cutting corners for disreputable engineers

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Although it's a service that that customers may request, the simple ‘boiler swap’ no longer exists; at least not legally. These days, fitting a new boiler means complying with a long list of regulations. On top of this, there is a raft of additional measures that should be undertaken to ensure that the new boiler has the best chance of a long and healthy life.

However, this means that a legitimate and competitive quotation for a fully compliant replacement boiler may seem expensive when compared to an estimate from a less reputable company that is willing to fl out regulations and take short cuts.

Below, we look at the main requirements that can be expensive to meet, and so unfortunately are frequently ignored:

1) Condensing boilers are compulsory in most situations under the Building Regulations, and they need a drain connection to carry away the condensate they produce. This can be simple to install or a major task adding a day or more to the work. Sometimes moving the boiler to a different location in the house is the only way to achieve the drain connection.

Potential cost saving from not fitting a condensing boiler: £100 to £1,000.

2) ‘Energy-efficient’ controls are now compulsory under the Building Regulations. Room thermostats and hot-water cylinder thermostats must be fitted, and conversion to ‘fully pumped’ pipework format is necessary unless already installed.

Potential cost saving from not fitting energy-efficient controls: Anything from £0 to £1000.

3) Pressure drops. A new gas supply pipe usually needs to be installed in order to comply with the latest HSE and Gas Safe guidelines on permissible pressure drops between the gas meter and the appliance. It is now up to the manufacturer to advise what pressure drop is allowed for their appliances, and this means that many existing gas supply pipes are too small. A new boiler will usually work perfectly well if connected to the existing pipe with insufficient pressure, but to comply with this new guidance a new, larger gas supply pipe usually has to be installed all the way from the meter to the new boiler. When boiler and meter are on opposite sides of the house this can add days of work, not including the restoration of disrupted decorations, etc.

Potential cost saving from re-using existing gas supply pipe: £0 to £1,000

4) Power flushing. Virtually all boiler manufacturers demand that their boilers are connected to clean heating systems, and will not accept warranty claims for failures caused by sludge or corrosion deposits in the circulating water. This means the existing radiator system should be cleansed before connecting the new boiler, and then a good quality inhibitor added to prevent future corrosion. A dose of decent quality inhibitor only costs around £25. No-one will know if this is skipped, until a few years later when the corrosion problems begin early, and the offending installer is long gone. Powerflushing is the most effective way to cleanse a system and it adds approximately a day’s work.

Cost saving from not powerflushing (including inhibitors): Around £60 per radiator; £480 on a typical eight-radiator system.

5) Pump over-run wiring. Condensing boilers have a device built into them to control the pump, keeping it running for a few minutes after the burners have shut down (to distribute the residual heat and protect the fragile high-performance heat exchanger). This means running an extra cable from the boiler location to the pump location (usually next to the hot-water cylinder upstairs in the airing cupboard). Installing this extra cable can be time consuming and disruptive to carpets and decorations, and the customer probably wouldn’t notice if the installer didn’t bother to connect up the pump over-run - until the heat exchanger fails a year later!

Cost saving from not installing pump overrun wiring: £100 to £1,000.

6) Gas Work Notification. This is a compulsory ‘service’ introduced by CORGI/Gas Safe Register. Gas engineers are now obliged to provide the Gas Safe Register with details of every gas appliance installed. Gas Safe Register will then provide the customer with a document certifying that the work has been carried out in accordance with the Building Regulations. This document becomes part of the ‘Home Information Pack’ (HIP) and may be required when the property is sold. Only engineers that have passed the Energy Efficiency Assessment can notify boilers. If you don’t receive the CORGI/Gas Safe Register notification certificate, then it is likely that the installation wasn’t notified, thanks to some of the above short cuts being taken or because the engineer was not qualified to notify.

There are plenty of other short cuts that a less reputable engineer may take, but these are the primary and the most common examples.

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