Overview

System accessories

An economiser is a heat exchanger that uses the residual energy of the flue gases to heat feed water. The economiser is installed on the flue-gas side between the steam boiler and the chimney. On the water-side, the economiser is installed on the boiler feed pump and the pressure vessel. The water to be heated flows to the flue gases to be cooled in a counter flow.

The advantages for you

  • An economiser increases the efficiency of the steam boiler significantly and is recommended in all cases
  • At low condensate return flow (<25%), the economiser may also be used to pre-heat the feed water in the feed water container.
  • Energy savings of up to 1%
  • In many cases, a second economiser has a short amortisation time

How it works

  • A steam boiler can only begin blow down once the blow down vessel has given a release signal. This is only given when the water level in the blow down vessel is below a target level.
  • The water is only drained when the target water level is exceeded.
  • The drained water is cooled with fresh water if the drain temperature is above the target value.
  • At low condensate return flow (<25%), the economiser may also be used to pre-heat the feed water in the feed water container. For this, the water is pumped in the circuit from the feed water container through the economiser back to the feed water container.
  • If the steam boiler requires water, the circuit is interrupted and the water is pumped from the economiser into the steam boiler. This requires an optional magnetic valve with the corresponding control.

The optional as-needed switching of the economiser from boiler water pre-heating to circulation of the feed water may lead to energy savings of up to 1%. The steam boiler pump pumps continually. If the steam boiler does not need any boiler water, the feed water is pumped into the feed water container in the circuit. This increases the flow rate in the economiser, the water temperature drops and the efficiency of the economiser rises.

THE SECOND ECONOMISER

The second economiser is a heat exchanger that uses the residual energy of the flue gases for heating water, such as:

  • the feed water supplied to the boiler
  • the fresh, softened water supplied to the feed water tank
  • Soft water for other uses

The second economiser is installed on the flue-gas side between the first economiser and the chimney. The water to be heated flows to the flue gases to be cooled in a counter flow. The lower the temperature of the flowing water, the higher the efficiency. The integration of the second economiser depends on the expected condensate return flow.

The reduced flue gas temperatures may cause the flue draught to be insufficient. The design of the chimney system should be re-calculated accordingly. For brick chimneys, i.e. without stainless steel lining, sooting must be expected.

Do you have questions?

Your JUMAG team is happy to assist you!

About us

For more than 40 years, we have been developing, producing and selling oil and gas-fired steam boilers.

JUMAG steam systems represent efficiency and user-friendliness.

Contact

Jumag Dampferzeuger GmbH
Badener Str. 8a
69493 Hirschberg

+49 6201 84603-0

DOWNLOADS

Contact

We are happy to advise you