US1935632A - Water heater - Google Patents

Description

Patented Nov. 21, 19.33" i William J. Handley, Jackson, Mich.

Application December 21, 1932 I Serial No. 648,163

This invention relates to hot weather heaters and has for its object, a hot water heater of the inverted U tube type which is adapted to better circulate the water and also to handle a large amount of the products of combustion when this is desirable.

In prior Patent No. 1,714,843, in which I am one of the joint applicants, an inverted U tube type of hot water heater is described and claimed. This heater is designed to operate with a minimum economy and uses a low consumption burner so that there is little waste in the exchange of heat units. This heater has been very successful for economic operation but where the demands on the 151water'heater are relatively great, this type of water heater is inadequate.

The inverted U tube type of heater, on the other hand; is not well adapted for handling a large quantity of the products of combustion for the reason that the U tube itself does not rapidly clear the products of combustion-infact, the principle of our prior invention actually is to retard the movement of theproductsof combustion so as to extract the maximum amount of heat units from the products of combustion before they are discharged. This is aided by the up and down; legs of the U tube which tend to balance each other and thereby retard the flow of the products of combustion. This principle operates very well and very nicely-with a low consumption burner but with a higher consumption burner a U tube" flue which isin approximate balance, will not op-' crate, satisfactorily for the reason that the downgoing flue will not take off the products of com- '35: bustion with sufiicient rapidityto suit the capacity of the burner and the needs of the heater.

Of course, this defect can be remedied by shortening the down-flue length but then the efiiciency of the heater is somewhat impaired by shortening 40. the time contact of the products of combustion with the water-surrounded surfaces; The products of combustion are discharged before it is desirable to remove them from the heat exchange relation with the water.

In my high demand water heater Iam enabled to use a U tube flue of substantially equal length for the up and down legs and at the same time operate with a fairly'high consumption burner so as to heat the contents of the tank in a shorter time. This will be more fully explained hereinafter.

The figure of the drawing is a longitudinal section of my improved heater.

In our prior patent, the rate of gas consumption 55.. is stated to be preferably 6 cubic feet per hour or 5 Claims. (01. 122-47) 3 cubic to 15 cubic feet per hour asadesirable range. This, of course, refers to artificial gas. In my improved heater Ipropose to use what might be termed a high consumption burner. For instance, I can burn gas at the rate of 60 feet per hour, where the gas is artificial, and 30 feet per hour where the gas is natural gas. This means, of course, that this is the rate of consumption if the burner is going continuously as would be the case if the water were being drawn off con- 5 tinuously.

q a represents the heat insulated tank, b the U tube, 0 the outgo hotiwater pipe, d the cold water feed pipe which discharges near the bottom. The high consumption burner is designated e and happens to be in the form of a ring burner. f

is a safety pilot lightJL is a thermostat that con trols the fuel flow. 2' is a bell-shaped end of the U tube into which the products of combustion discharge. This initial' combustion chamber or bell extends downbelow the bottom of the water tank. This furnishes an initial hot chamber which can be kept considerably hotter than may be the case if this chamber were entirely surrounded by cold water. Heat units are not taken from the 30 chambernearly so rapidly as less than half of this chamber is exposed to the cold water. The result is that this enlarged combustion chamber with a large portion not exposed to the cold water, serves to force the productsof combustion up through 35 the Utube with greater energy than wouldotherwise be the case because of the more unbalanced condition. This aids in forcing the products of combustion down through the down leg so as to clear the flue in accordance with the capacity of the burner.

However, the element that greatly aids in the rapid passage of gases through the U tube is the use of a copper insert tube 7' in the down-leg of the flue. This tube connects with the contents of the water tank near the bottom and also near the top of the down-leg. This forms a circulating tube and is very useful for causing the cold water from the bottom to be heated in this tube and flow to the top. This creates a constant circulais the case in our prior patented device #1,?14343. It brings more of the water into a very immediate contact with the products of combustion and therefore is enabled to extract additional heat units from the rapidly moving column which would otherwise be lost. A third extremely useful function in connection with this particular design of heater is that by reason of this abstraction of additional heat units, it cools the products of combustion in the down-leg and facilitates their flow downwardly so as to clear the flue in accordance with the necessities of the capacity of the burner. Without this circulating tube where it is, it would be necessary toeither lengthen the up-flue which cannot be done very readily from a constructional and convenience stand point,,or else to shorten the downflue. If the down-flue is shortened, then the maximum heat exchange in the down-flue is not achieved and that much efficiency is lost, Not only is the maximum length of the down-flue achieved but additional heat exchange efiiciency is secured by reason of the presence of a small portion of the water in immediate relation with the down-going products of combustion. r 1

In using the word U tube in the description, and claims, I want it understood that Ido not use it in the narrow sense of a single tube of uniform cross-section. A great many variations of this can be had, as for instance, a large central up-going flue with a plurality of smaller down-going flues, and these several flues, or this central flue, may be of various sizes and kind. In using the term circulating tube as described, it is to be understood that this is not used in the narrow sense of a single straight pipe but covers any form of tube or tubes that accom plish the described results.

What I claim is:

1. In a water heater, the combination or" a water tank, an inverted U shaped tube in the tank, both legs of which are surrounded by water in the tank, said legs forming an upgoing and a downgoing flue, a burner positioned to discharge products of combustion into the upgoing flue, and a water circulator tube in the downgoing flue communicating into the tank adjacent the upper and lower ends of the downgoing flue.

2. In a water heater, the combination of a water tank, an inverted U shaped tube in the tank, both legs of which are surrounded by water the downgoing flues. in the tank, said legs forming anupgoing and a downgoing flue, a high combustion burner positioned to discharge products of combustion into the upgoing flue, and a water circulator tube in the downgoing flue communicating into the tank adjacent the upper and lower ends of the down 3. In a water heater, the combination of a water tank, an inverted U shaped tube in the tank, both legs of which are surrcunded by water in the tank, said legs forming an upgoing and a downgoing flue, a high combustion burner positioned to discharge products of combustion into the upgoing flue, and a water circulator tube in the downgoing flue communicating into the tank adjacent the upper and lower ends of the downgoing flue, the lower end of the downgoing flue projecting out of the tank for the discharge. of products of combustion.

4. In a water heater, the combination of a water tank of relatively great height as compared with its' cross-section, a substantially inverted U shaped tube in the tank, the ends of which extend through the tank walls, both legs of the U shaped tube being surrounded by water in the tank and forming an upgoing flue and a downgoing flue, said flues extending through the major portion of the height of the tank; a burner positioned to discharge products of combustion into the end of the'upgoing flue, the end of the downgoing flue providing for discharge of products of combustion, and a water circulator tube in the downgoing flue communicating into the tank adjacent the upper and lower ends of the downgoing flue.

5. In a waterheater, the combination of a water tank, an inverted U shaped'tube in the tank, both legs of which are surrounded by water in the tank and which form upgoing and down going flues, the upgoing flue having an enlarged portion at its lower-end positioned in the bottom wall. of the tank so that part of the enlarged portion lies within the .tank surrounded by water and a part lies outside the tank, a burner positioned below the said enlarged portion for discharging products of combustion into theupgoing flue, the lower end of the downgoing flue extending through the tank wall for discharge of productsof combustion, and a water circulator tube in the downgoing flue communicating into the tank adjacent the upper and lower ends of WILLIAM J. YVHANDLEY.

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