Furnace Sizing

Furnace sizing is essential to avoid wasting energy. If the furnace is too big, both energy and money is wasted. If the furnace is too small, not enough heat will be generated for the house.

Influencing Factors

These include the total square footage, geographic location, insulation type and heat loss from windows. Other factors are the locations of wires and pipes. The design of your current furnace is another factor.

Assume you have a split level home with a couple of operating zones for heat management. If there are occupants in only one zone at a time, less BTU will be needed. BTU (British thermal unit) is how furnace sizing measurements are determined. If there are two or more controlling zones in the area, the dimensions of a furnace will be different.

Heat Loss Calculation

The easiest way to determine the furnace you need is to hire a company to evaluate the heat loss in your house. The heat loss, along with the other factors mentioned earlier, will determine what type of furnace you need.

If you want to calculate heat loss yourself, here is how it’s done. The calculation is based on utility bills and utilizes a three meter reading. When making heat loss calculations to determine furnace sizing, at least a couple of weeks of winter weather is required.

The goal of the calculation is to locate the relationship between the heating degree days (HDD) and the gas consumed. After this is attained, you have to figure the gas consumption for design temperature. HDD and design temperature records can be obtained from building officials.

Sample Calculation

The total gas consumption from December to March is 1,320 m3. The estimated consumption for other gas appliances is 306 m3. The gas consumption for heating used during this time is 1,320 – 306 = 1,014 m3. For this furnace sizing calculation, the heating degree days are 2,840 HDD.

The heating consumption against the degree days: 1,014 m3/ 2,840 HDD = 0.3570 m3/HDD. The heat consumption at 53 HDD/day (53 HDD/day/0.3570 m3/HDD) is 18.9 m3/day. If the gas energy is 37.5 MJ/m3 and the furnace has 72% efficiency, then the loss is 53 HDD/day = (18.9 m3/day) (37.5 MJ/m3)(0.72) = 510 MJ/day or 21.3 MJ/h.

Because 3.6 MJ/h is equal to 1 kW, 21.3 MJ/h is 5.9 kW. Using this calculation, the required furnace must have a BTU of 20,100 BTU/h. If a 40% over sizing is allowed, the furnace would have to be 28,100 BTU/h.

Hiring a Technician

Because the calculations can be complex, most people prefer to hire a company or technician to determine furnace sizing and heat loss. Make sure the technician is qualified to do this. The costs will vary, so getting price quotes will be essential.

Output and Input Capacity

The input capacity refers to the gas burning without considering heat loss by flue. The output capacity denotes the entire usable heat produced.

Furnace sizing is a complex issue, and precise calculations are needed. If you’re not sure how to do this, hire a professional.

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Dimensions of a Cheque

Dimensions of a Cheque

Primarily a negotiable instrument, a cheque instructs a bank or other financial institution to pay a specified amount of money of a particular currency to a particular person or institution. Legal entities or individual persons can serve as payees and makers. From 1600s to 1900s, different kinds of spellings were used to refer to this kind of negotiable instrument. The term ‘check’ is the common spelling in American English, while the word ‘cheque’ is used in Ireland. In addition to these interesting details, it is also good to know the dimensions of a cheque.

The Dimensions of a Cheque

The standard size of cheques is 46 centimeters by 91 centimeters or 18 inches by 36 inches. Based on the Guinness Book of World Records, the largest cheque ever made measured 12 meters by 25 meters or 39 feet by 82 feet. No matter how big or how small it is, the amount of money that can be redeemed depends on the value written on it. It is quite common for some banks to seek additional charges for oversized cheques.

Additional Facts and Other Interesting Details

A cheque is comprised of various elements including the date of issue, the cheque number and the place of issue. Aside from this, it also contains the signature of the drawer, the amount of currency as well as the payee. A routing transit number is also included. In the United States, this element is made up of nine digits. The first four digits are part of the cheque-processing center of the U.S. Federal Reserve Bank.

In the United States, the Uniform Commercial Code states the rules governing the use of the three different types of cheques, namely the counter-cheque, the bearer cheque and the order cheque. Alternatives to cheques include direct credit, direct debit and wire transfer. In addition to these, it is also possible to use a postal payment, a third-party online payment service and an online card payment.

Cheques are susceptible to different kinds of fraud, one of which is identity theft. Every cheque is made up of different kinds of personal details such as the signature, account number and name. Other cheques contain even the phone number, address as well as the driver’s license number.

It is possible for a cheque to be dishonored. In case this happens, it will become worthless. This kind of cheque is called NSF, which stands for non-sufficient funds. In other times, it is referred to as a returned deposit item or simply RDI. In Wales and England, a dishonored cheque is marked with the statement ‘Refer to Drawer.’