Operating Instructions and Installation Instructions

LR, LRK, LR-NT, LRK-NT 21 - 32

We reserve the right to make changes to dimensions and construction 3 edition 30.10.2007

2. Description

2.1. General information

Pyronox LR boilers are high efficiency, power-saving boilers ranging from 530 to 3000 kW and from 450 to 2600

kW for low-NOx applications. They can be operated in combination with oil or gas burners.

The Pyronox LR boiler range are three pass, smoke

tube boilers with combustion chamber and flue way

using the Low-Nox technology. The geometry of the

furnace, the furnace’s low charge, coupled with the

Ygnis patented flame escape system, allow users to

obtain low emission values and safe operation in

conformity with law provisions.

lr_4-26a.SKD

LR355-7.SKD

Upon request, the Pyronox LR and LRK boilers are also

available with an integrated and watercooled flue gas

recirculating system (ARF).

The third pass is equipped with turbulators. Their turbulent action further increases the heat exchange and allows

the system to work at low combustion gas temperatures, guaranteeing optimal fuel use as a result.

The boiler’s thermal insulation is made of glass fibre felt that adheres to the boiler shell, guaranteeing minimal loss

in stand-by mode. In addition, the front part of the boiler is provided with superior quality ceramic fibre insulation.

The outstanding characteristics of the material are the low thermal conductivity and the low specific thermal

capacity. This leads to a further reduction of the stand-by losses.

A soundproofing hood can be optionally provided that covers the whole of the front of the boiler, with which burner

and ARF-ventilator noise can be kept down to a minimum and thermal radiation can be further reduced.

A revolving door gives easy access to parts of the boiler that are in contact with combustion gases. This allows

cleaning of combustion chamber and passage ways to be easily performed from the front. The turbulators are

retractable from the front. The combustion gas collector on the rear of the boiler is provided with an opening for

easy cleaning.

The boiler’s thick casing is easy and quick to install. Casing plates are painted with an environment-friendly paint,

so they are permanently protected from corrosion.

In the LR-NT version, the boilers in the back part of the third pass is equipped with jacketed pipes and the water-

impacted part of the smoke box is double-walled. This prevents the flue gases from condensing out, even with

return temperatures below the usual limits. This version thus allows operation under return conditions that are only

possible using low-temperature boilers.

The LRK version is equipped with an integrated flue

gas recuperator made of special stainless steel that

is also designed for operation with oil and/or gas

burners. In this combination, the LRK becomes a

condensing unit that uses the condensation heat of

the steam present in the flue gases. As a result, the

efficiency can increase to over 107% (in relation to

the lower calorific value) at a correspondingly low

return temperature.

lrk4-261.skd