As you may be aware the UK government's boiler scrappage did not include for the replacement of gas fired warm air heaters, this is because warm air heaters are taken to be inherently more efficient than older boilers and therefore less in need of scrapping to meet the government's carbon emissions target. However, with the unmatched efficiency of the Lennox G61MPVT heaters there are still enormous benefits in updating existing warm air installations.

Although the government's boiler scrappage scheme has finished in England we are still comitted to saving you money on your heating costs and minimising environmental impact. The boiler scrappage scheme promoted the use of condensing boilers in existing central heating installations as it specifically targeted direct replacement of old, low efficiency, boilers with modern condensing boilers. One flaw of this concept is that by using existing radiators designed to work with the old boiler the return water temperature can be too high for a condensing boiler to work at its design efficiency and it may actually operate most of the time as a non-condensing boiler.  The Lennox G61MPVT gas fired warm air heater will always condense at normal operating conditions because it directly heats the air (typically at 21°C or less) rather than water (often at 70°C or more). 

You may have heard or read about heat pump technology as an environmentally friendly alternative to conventional heating, however, heat pumps in general work well when the outside air temperature is above the optimum balance point, typically 7°C as below this their efficiency drops off.

Now it is possible to combine the benefits of heat pump technology with the benefits of the Lennox G61MPVT condensing gas fired warm air heater to optimise efficiency throughout the year.

We can offer the Lennox G61MPVT heater to work in conjunction with a Lennox heat pump system fitted with a Lennox dual fuel thermostat linked to a outside air temperature sensor set to 7°C so that the system will work in the heat pump mode at temperatures above 7°C  but when the temperature gets to 7°C or below the heat pump is turned off and the Lennox gas fired warm air heater is used instead.  This system can also provide you with the additional benefit of air conditioning in the summer months and Lennox and ourselves are offering a special equipment package price for any purchases made before the end of May 2010.

We can offer the Lennox G61MPVT heater to work in conjunction with a Lennox heat pump system. This will allow you certain advantages in terms of running costs and below we detail some information on a typical heat pump system installed and linked to a Lennox G61MPVT unit.

In terms of relative running costs:
The heat-pump heating capacity and power consumption varies depending on outside temperature, the G61 gas consumption and heat output varies between low fire and high fire (2 stage heating operation).
Taking a fairly typical cost for both electricity and gas of 3.107p/kWh for gas and 9.675p/kWh for electricity:

The running cost (gas) per hour for the Lennox G61MPVT--60D-135 on HIGH output is 120p, this is equivalent to 3.37p for each useful kW of output.
The running cost (gas) per hour for the Lennox G61MPVT--60D-135 on LOW output is 82p, this is equivalent to 3.21p for each useful kW of output.
The running cost (electricity) per hour for the Lennox HP40-036 at 18°C outside temperature is 35p, this is equivalent to 2.65p for each useful kW of output.
The running cost (electricity) per hour for the Lennox HP40-036 at 7°C outside temperature is 32p, this is equivalent to 3.13p for each useful kW of output.
The running cost (electricity) per hour for the Lennox HP40-036 at -4°C outside temperature is 29.7p, this is equivalent to 3.86p for each useful kW of output.

This shows that, although the heatpump is less expensive to operate in mild conditions (7°C or higher) it becomes more expensive to run at low temperatures and has a lower heating capacity which may be insufficient to meet your requirements in winter conditions.
With appropriate controls the G61MPVT--60D-135will operate mostly in LOW output to maximise efficiency, HIGH only being required in the coldest conditions or for warming the house from cold.

The system will require a dual fuel thermostat (Lennox Comfort Sense 7000 with External Sensor) for it to function and operate efficiently