Updated: 22 Apr 2010

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Introduction

We tested 5 built-in flued gas fires suitable for a fireplace or fire-proof wooden frame.

If you want lots of heat and real flames, then a flame-effect gas fire could be just the ticket. Running costs are higher than for a woodburner or heat pump – but you can't toast yourself in front of a heat pump or just press a button to light a woodburner.

We assessed performance, safety and ease of use, and looked at the "greenness" of natural gas and LPG.

Models we tested

This report contains test results and recommendations for the following flued gas heaters:

About the heaters

We tested built-in models suitable for a fireplace. These can also be enclosed in a fire-proof wooden frame, which is probably the best option for new homes or for older homes being renovated.

All these heaters had a “balanced flue”, which consists of one tube sitting inside another tube. The exhaust gas goes out through the central tube and the combustion air is drawn in through the gap between the tubes. With some models a fan is added to the flue system – this is called a power flue.

So in most of the models the exhaust can go up an existing chimney or out through a wall. The Kent is the exception – it has to exit horizontally.

Drawing the combustion air from outside increases the efficiency of the heater (the combustion air is pre-warmed by the exhaust) and it reduces draughts inside the house because the combustion air is not being drawn from the room.

The Heat 'N' Glo had a back-up battery facility – so it could operate during a power cut.

Capital cost

These heaters aren’t cheap. They’re possibly more expensive than an equivalent-sized heat pump and certainly more expensive than a woodburner. Installation costs would vary according to the house’s layout. Make sure you get several quotes before you go ahead.

Running costs

Gas heaters are comparatively expensive to run. Our heating costs survey showed that woodburners were cheapest, followed by heat pumps. The cost of operating a gas heater depends on how you factor in the connection cost (for natural gas and reticulated LPG) or the gas-bottle costs (for bottled LPG).

If you already use gas for cooking or hot-water heating, then these “overhead” costs will be shared over more than one appliance (which brings down each appliance’s running costs). Your running costs are higher where you use gas just for heating.

How green is gas?

At first glance, gas isn’t at all green. Both natural gas and LPG are fossil fuels; burning them adds to greenhouse gas emissions.

But how does gas stack up against its alternatives?

A heat pump may seem greener because it uses electricity and most of our electricity is generated from renewable hydro and wind sources. However, during winter those sources are supplemented from coal- and gas-fired sources – so winter electricity is only semi-green.

Wood is a renewable resource. But the big woodburner problem is atmospheric pollution. Even the cleanest of modern woodburners emit fine-particle pollution in their smoke. Those particles can lodge in people’s lungs and cause respiratory problems. And it's not just Christchurch and Nelson that have problems: there are many places that regularly exceed our air-quality standard.

Gas fires emit greenhouse gases but are otherwise nearly pollution-free. And, on balance, we think burning gas directly for heat is an effective use of the resource … possibly more effective than turning it into electricity for heating.