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HVACR316 - Piping

Related Codes IIITrade Math III

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Codes

• The codes related to the field testing of refrigerant piping can be found in;

• Mass; CMR-522• Conn; International Mechanical Code

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Related Codes

• Field Testing refrigerant piping – every refrigerant containing part of every system that is erected on the premises, except compressors, condensers, vessels, evaporators, safety devices, pressure gauges and control mechanisms that are listed and factory tested, shall be tested and proved tight after complete installation, and before operation.

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Related Codes

• Tests shall include both the high and low pressure sides of each system at not less than the lower of the design pressures or the setting of the pressure relief device.

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Related Codes

• The design pressures for testing shall be those listed on the condensing unit, compressor or compressor unit nameplate.

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Related Codes

• Test Gases – tests shall be performed with an inert dried gas including, but not limited to, nitrogen and carbon dioxide. Oxygen, air, combustible gases and mixtures containing such gases shall not be used.

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Related Codes

• Test apparatus – The means used to build up the test pressure shall have either a pressure limiting device or a pressure reducing device and a gauge on the outlet side.

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Related Codes

• Declaration – A certificate of test shall be provided for all systems containing 55 pounds or more of refrigerant. The certificate shall give the name of the refrigerant and the field test pressure applied to the high side and the low side of the system. The certification of test shall be signed by the installer and shall be made part of the public record.

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Trade Math

• You will need your tape measure for this section.

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Trade Math

• Reading a Ruler – The basic measuring tool is the ruler. A ruler is divided into equal parts or inches.

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Trade Math

• Each inch is divided into equal fractional parts of an inch. The fractional parts are halves (1/2), quarters (1/4), eights (1/8), and sixteenths(1/16).

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Trade Math

• The 1 inch line is the longest, the ½ inch line is the next in length, the ¼ inch line is the next in length and so on down to the line representing 1/16 of an inch which is the shortest line.

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Trade Math

• The first line on the left side of the ruler indicates one 16 of an inch which would be the number of division per inch on that ruler. The second line would represent 2/16 of an inch or 1/8 of an inch. The third line on the ruler would represent 3/16 of an inch. The fourth line on the ruler would represent 4/16 of an inch or ¼ inch.

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Trade Math

• Solve these Problems:

1. In 1 and ½ inches there are how many 16ths?

2. In ½ inch there are how many 16ths?3. In ¾ of an inch there are how many 8ths?4. In 1 and 4/16 there are how many 8ths?5. 20/16 reduced to its lowest term is

______?6. In 2 and ½ inches there are how many

16ths?

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Trade Math

• Problems, cont’d.7. 12/16 reduced to its lowest term is

_____?8. In 5/8 there are how many 16ths?9. In ¾ there are how many 16ths?10. 15/8 reduced to its lowest term is

_____?

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Trade Math• Answers:

1. 242. 83. 64. 105. 1 ¼ 6. 40

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Trade Math

• Answers, cont’d.

7. ¾ 8. 119. 1210. 1 and 7/8