GB2474918A - Condensate drain heater for a boiler - Google Patents

Abstract

A condensate drain heater apparatus for a boiler prevents the condensate from freezing by providing an airflow through the condensate drain. Preferably, the apparatus uses ambient temperature air from an internal room or space as a heat source, which when drawn and pushed through the condensate drain raises the air temperature, thus preventing freezing. Additionally, the heat of components within the boiler casing may be used as a heat source, which when ducted to a fan unit 2 could be used to raise the air temperature. Advantageously, an internal heating element is provided for further raising the airflow temperature. The apparatus may include a one way valve to satisfy safety regulations, where the valve may be a flap type with a spring loaded fulcrum 4. In use, the apparatus preferably includes a high velocity fan to provide airflow through the condensate drain to the outside, where the fan is operated when the external temperature is at or near freezing.

Description

Title: Condensate Heater This patent application applies to condensing boilers of any fuel type.

Modem boilers are high efficiency designs, as a byproduct of their high efficiency condensate liquid (or condensate as it is known) is produced.

The main problem with condensate liquids is that they are susceptible to freezing rapidly, if the condensate drain on a boiler freezes it will render the boiler inoperable, obviously this is a major problem.

Statement of intention

To resolve this my invention would be incorporated to the condensate drain and in cold conditions would operate to prevent the drain blocking.

Advantaaes Due to the condensate not freezing, the appliance will continue to operate regardless of the external conditions resulting in the boiler remaining operational.

Description

The key principle of the condensate heater is of constant airflow through a drain preventing freezing by utilising key principles of fluid dynamics and thermodynamics.

* Constant airflow over the fluids surface will reduce ice seeding points through evaporation and by creating movement on the fluids surface making it more difficult for freezing to initiate.

* The internal air temperature of the condensate drain will be positively affected by the airflow temperature due to the enclosed environment of a condensate drain, a plastic pipe with a large proportion containing air (95%) the condensate in that pipe will absorb the internal air temperature of the pipe, and as plastic is a natural insulator, the external air temperature will have less of an effect over the condensate.

There are 3 possible variations of the condensate heater that can be applied depending on the severity of the outside environment temperature; i) The condensate heater would just use airflow only, taking airflow from an internal room and pushing that through the condensate drain.

ii) The condensate heater would take the air temperature of inside the boiler casing, using the warmer air as a heat source.

iii) The condensate heater would use an internal heating element which further raises the airflow temperature.

Explanation of drawincis Diagram 113 The condensate heater would be installed downstream of the condensing boilers condensate outlet, because of the design, it could be installed vertically or horizontally.

1. Shows the condensate inlet to the heater unit 2. Shows the high volume fan unit which draws air in from the internal room (thus ambient temperature from inside a house) 3. Shows a one way valve required to satisfy safety regulations, this one way valve is a flap type of valve with a fulcrum at 4 which would be spring loaded 4. Shows a spring loaded fulcrum.

5. Shows the venturi I baffle which directs the airflow to the outlet of the unit, creating neutral I negative air pressure behihd it and prevents surging of condensate flow.

6. This is the outlet of the condensate heater which runs on to an external open drain.

7. Shows a flexible tube which if required would terminate inside the boiler casing, using the heat off the warm hydraulic components to increase the air temperature through the condensate, typically this would be fitted if the boiler was located in a garage I out building which would have a much colder room temperature.

Diaciram 213 1. Illustrates the wireless transmitter unit which at given temperature i.e. +lc would send a signal to (3.) a wireiss switch / receiver. This transmitter 2. Shows a transformer connected 240 v (AC) to 12v (DC) to the boiler with live, neutral and earth connections 3. Shows the wireless receiver unit which switches supply to (4.) the fan unit Dlaaram 313 This is an alternative design on the same principle (airfow). Showing how the orientation of the components are different and the one way valve is different 1. This is the inlet to the heater unit (downstream of the boilers condensate trap) 2. This is the air inlet from the internal room.

3. This is the baffle I silencer made of sounds deadening material which still allows airflow through it.

4. Shows the fan unit in a different orientation.

5. Shows the flap type one way valve made of flexible rubber.

6. Shows the outlet of the unit where airflow would go out of.

7. Shows the restrictor which is U shaped in the tube preventing surge of condensate.

Claims (4)

1. Claims 1. Preventing condensate freezing using airflow through the condensate drain.
2. 2. The condensate heater being universally acceptable to any make and model of boiler.
3. 3. Using the ambient room temperature as a heat source which when drawn and pushed through the condensate drain raises the air temperature thus preventing freezing.
4. 4. Using latent heat of the components as a heat source with in the boiler casing which when ducted to the fan unit will raise the air temperature further more.