Epdm Rubber Tube In Ground Heating

EDPM Rubber Tube
in Ground Heating

The DELTA-TUBE™LD EPDM rubber tube heating system heats the greenhouse at the soil level where the heat is needed. Heat rising from the bed warms the soil and plant roots. By controlling the soil temperature both rooting and plant growth can be accelerated.

Growers that use our ground heating systems have shown 30% reduction of fuel usage along with shorter production times and superior product quality. This material excels in the nursery industry for general growing and rooting of cuttings and is ideal for starter houses. Growers that use this material for heating soil or nutrient bags of tomatoes and cucumbers have shown a 50% increase in yield. Grape growers have found a quicker and more even call using pattern by using bottom heat to callus grape stock.

DELTA-TUBE EPDM rubber tubing is ideal for use in a hot water heating system due to its resistance to temperature and chemicals and its superior heat transfer capabilities. Small tube design reduces the system water volume and enables it to respond quickly and efficiently. Tubing spaced 4 to 6 inches apart provides even temperatures to the soil and the crop for optimum environment of all types of growing.

The Delta Tube manifolds use a unique plastic fitting that is pressed into the PVC pipe creating a water tight fit that is guaranteed not to leak. Each fitting is pressed into the top of the manifold so that the tubing is easily installed. Each manifold is custom manufactured
for each system.

The exclusive tubing spacers secure the Delta T tubing at the optimum design spacing. They are cut to the bed width for ease of installation.Maximum length is 8 foot.


The hydronic heating system is the DELTA-TUBE™ LD EPDM rubber tube system using 135°F water temperature and will consist of the followingcomponents:

  • 1.5″ Manifolds with plastic adapters pressed fit into SCH 80 PVC pipe cut to the bed width. All fittings shall be installed on
    top of manifold for easy connection of tubing.
  • Ridged plastic spacers with spaces every 2 inches holds the EPDM tube in place and space tube on 10 foot spacing. Spacers are cut to bed width up to 8 foot long.
  • High quality EPDM rubber tubing 0.30″ ID x 0.45″ OD shall be on inch centers. Tubing shall be able to resist ozone,chemicals,fertilizers and temperatures up to 230°F. Tubing shall be provided on 1,000 foot spools for easy handling.

Some of the many advantages of the DELTA-TUBE™ LD systems are:

  • Direct contact from tubing to root zone for maximum soil and plant temperature control.
  • Even temperatures are maintained throughout the system resulting in even crop growth.
  • Compatible with any type of hot water heat source.
  • Different temperature zones for flexible growing.
  • Cost effective system for the grower that wants to get into a hot water heating system inexpensively.
  • 1.5″ plastic manifolds make it easy to install on plastic mainlines.
  • Special pressed fit barb fittings installed on top of manifold make installation of tubing neat and quick.
  • Long ridged spacers can easily be installed without having to install more than two or three fasteners.
  • High quality tubing withstands UV light, fertilizers, and high temperatures.
  • Flexible tubing is easily installed and comes in 500 foot rolls.

Delta T Solutions can provide a performance engineered heating system that can meet the needs of any grower. Performance packages include: Heating system components (heat source, controls, radiation), performance engineered drawings (pipe layouts and electrical diagrams), installation supervision, installation (as required). Contact your local Delta T Solutions Representative for additional details.

Delta Tube™ LD Ratings
  BTU/SQ FT output (average water temp.) Volume
Tube Spacing 100° F 110° F 120° F 130° F 140° F 150° F 160° F 170° F 100 SF
4″ 46 57 69 81 92 104 115 127 1.1 gal.
6″ 30 38 46 54 61 69 77 84 .73 gal.