Heaters with feed and air preheated by hot flue gas and hot residue oil respectively have attracted extensive attention.

管式加热炉采用“冷进料、热油预热空气”以提高热效率，受到了广泛的注意。

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Fuel oil and lubricating oil sy stems including pumps, purifiers, filters, heaters.

滑油管系，包括泵、分油机、滤器、加热器和管系状况满意，无泄漏。

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High thermal utilization factor, resource as steam, electricity and heating, coal, oil, fuel heaters, etc, could be used according to the user's situation.

热利用率较高，可依用户情况选用蒸汽、电加热、燃煤、燃油、燃气炉等。

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Depending on an applicant's needs, it will pay for things such as loft insulation, draught proofing, gas room heaters with thermostat controls, gas, electric or oil central heating.

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