Description
Every water source or geothermal heat pump needs two flexible connections to the building loop, one on the supply side and one on the return. This kit gives you both in one order: two matching ChamFlex 1-1/4" x 18" stainless steel braided hose assemblies (part number CH125018FM1000), so both sides of the unit are the same size, length and rating.
ChamFlex hoses are built by Chamberlin Rubber Company in Rochester, New York, and are a common choice on commercial and residential water source jobs.
How it is built
A white Santoprene inner tube carries the water, and a 302/304 stainless steel braid wraps it for strength and protection. One end has a fixed male pipe thread fitting. The other end has a male 37 degree JIC flare with a removable swivel adapter that converts it to male pipe thread, so you can tighten the hose into place without twisting the braid. The flare joint seals metal to metal, with no washers, gaskets or O-rings to wear out, and the pipe thread ends come with sealant already applied at the factory.
The 1-1/4" size is rated for 400 psi working pressure and 1600 psi burst, and it handles fluid temperatures from -40 to 212 degrees F. That covers closed condenser water loops, geothermal ground loops and boiler and tower systems running water or glycol. The inner tube carries a UL94 V-0 rating and the full assembly earned a Class A fire rating under ASTM E84, which makes it a good fit above ceilings and in return air spaces where codes call for it.
Water source heat pumps from ClimateMaster, Comfort-aire, Bosch, Carrier and GeoStar use female pipe thread water connections, so these hoses thread directly into a 1-1/4" unit connection and into your loop piping without extra fittings.
Key Features
- Swivel end: The JIC swivel adapter lets you snug the hose into position without twisting it, even in tight closets and ceilings.
- Pressure rating: Rated for 400 psi working pressure with a 1600 psi burst rating.
- Fire rated: Class A fire rated assembly with a UL94 V-0 inner tube, recognized under UL 207.
- No gaskets: The metal to metal flare seal has no washers or O-rings to dry out or leak over time.
Frequently Asked Questions
How do I know which hose size I need?
Match the hose to the water connection size on your unit, which you will find in the installation manual or on the submittal sheet. Most residential and light commercial units use 1/2", 3/4" or 1" connections, and larger commercial units can use 1-1/4". As a guide, ChamFlex recommends a maximum of about 30 gallons per minute through a 1-1/4" hose.
What comes in this kit?
Two ChamFlex 1-1/4" x 18" hose assemblies, one for the supply and one for the return. That is everything you need to connect one unit to the loop.
Which length should I pick?
Choose a length that reaches with a gentle loop rather than a straight pull. ChamFlex warns against installing hoses stretched tight, because the hose grows and shrinks a little with temperature and pressure. A longer hose also gives you more room to slide the unit out for service later.
How tight can I bend it?
Keep the bend radius at 10" or larger and avoid bending the hose right at the fittings. If a run needs a sharp turn, use an elbow at the connection instead. Do not install a hose that has been kinked.
Do I use thread tape on the connections?
Do not use tape or sealant on the flare joint, since it seals metal to metal. The pipe thread ends already have sealant from the factory. Install the fixed pipe thread end first, letting the whole hose turn with it, then thread the adapter into the other port and finish by tightening the swivel onto the adapter.
Can I use it for drinking water?
No. ChamFlex hoses are made for closed loop water and glycol systems only and are not rated for potable water.
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