Burnham 81441001R8-3/06 To Design Series-Loop Base-RayInstallation, Table a Table B

To Design Series-Loop Base-Ray®Installation –

1.Calculate the Heat Loss of each room using the procedure outlined in the I=B=R Heat Loss Calculation Guide No. H-21 or the ASHRAE Guide.

2.Using 210°F as design water temperature and 500 lbs/hr. as Àow rate, select length of BASE-RAY Assembly for each room to produce desired output. (Design water temperature other than 210°F may be used but should not exceed 230°F.) If system designed on 20°F drop, this 210°F average water temperature means roughly, that under maximum load conditions, the water leaves the boiler at 220°F and returns at 200°F and returns at 200°F. Since maximum load conditions occur only at rare intervals, the system usually operates at considerably lower water temperatures.

3.Locate BASE-RAY Assemblies on Floor Plan drawn to scale.

4.Layout Piping on Floor Plan as illustrated. Since the temperature of the water decreases progressively from the ¿rst Heating Unit to the Last Heating Unit on a circuit, the system should be laid out, if possible, so that the Heating Units with the hotter water are in areas such as the living room, bath and dining room. Heating Units in bedrooms, kitchen and similar areas should be located on the end of the loop.

5.Measure length of Circuit (horizontal and vertical) from boiler supply to boiler return (include BASE-RAY lengths). In Series Loop Systems, on rare instances a BASE-RAY Assembly, Radiant Radiator or Slenderized Radiator is connected to the main with branches. Since a one-pipe ¿tting is used, add 12 additional feet to the measured length to obtain total length of Circuit.

6.Knowing the load-length of the loop from Steps 2 and 5 above, Table A will indicate whether or not a standard ¾” or 1” circulator is adequate.

TABLE A		TABLE B
Btu/Hr. Output of	Total	Btu/Hr. Output of	Length of
BASE-RAY		BASE-RAY
	Length of		Longest
Assemblies Each		Assemblies All
	Loop Ft.		Loop - Ft.
Loop		Loops
40,000	100	50,000	240
35,000	135	55,000	210
30,000	175	60,000	165
25,000	260	65,000	140
		70,000	120
NOTE: Table based on 20°F		NOTE: Table based on head
		developed by Standard ¾" or

Drop through Circuit - ¾"

1" circulator - 20°F Drop

piping

through system.

If, for a given output, the total length of the loop exceeds the values shown in TableA, the loop may be split into two circuits

–see Illustration. Check load-length of each circuit. Determine from Table B if 1” trunk is adequate.

For Piping Arrangements and Design conditions other than those given above, follow procedure outlined in I=B=R Instal- lation Guide No. 200.

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