Danfoss DHP-A Service Instructions Manual

Also see for DHP-A: User guide User manual Installation and service instructions User manual Installation and service instructions

Contents

Danfoss DHP-A Service Instructions Manual Manual pdf 39 page image

Name SettingDanfoss TUBE R407C, 11.0 kW From fully closed position, screw 6.25 turns outDanfoss TUBE R407C, 17,0 kW From fully closed position, screw 5,5 turns outTable 12. Break pressure switchesRefrigerant Pressure switch Break pressureR134a (Only applies tocertain models ofDHP-C)Low pressure switch 0.03 MPaOperating pressure switch 1.80 MPaHigh pressure switch 2.45 MPaR404A (Only applies toDHP-A, DHP-AL)Low pressure switch 0.08 MPaOperating pressure switch A 2.65 MPaOperating pressure switch B 2.85 MPaHigh pressure switch 3,10 MPaR407C Low pressure switch 0.08 MPaOperating pressure switch 2.85 MPaHigh pressure switch 3,10 MPa10.4 Operational problemsThe tables in the following section apply to all types of heat pump and collector solutions.The tables list the most probable and common causes of the problem first. When troubleshooting the cause of aproblem start with the first cause and go down the list. There may be more than one way of troubleshooting acause where the most probable is given first.10.4.1 AlarmTable 13. Problem – Alarm LP (low pressure switch)Cause Troubleshooting Remedy1. Blocked strainer on the brine circuit. Check that the strainer is not blocked. Clean the strainer if necessary.2. Air in the brine circuit. Listen for air in the heat pump and brinecircuit.Bleed the brine circuit according to theinstallation instructions.3. Closed taps, main tap or filler cockon the brine circuit.Check that the shut-off cock or any othertaps are open.Open closed taps.4. The circulation pump for the brinecircuit is defective or has jammed.Check:• That the circulation pump spins.• That the shut-off valves are open.• That the strainer is not blocked.• That there is no air in the heating sys-tem.The circulation pump may have jammed.If so, open the bleed screw and try torelease the paddle wheel using a screw-driver for example.Open closed valves or taps.Check, and, if necessary, clean thestrainer.If necessary, bleed the heating systemaccording to the installation instructions5. Cable break or loose cable to lowpressure switch. • Check that both cables are connectedto the pressure switch.• Using the buzzer, check that there areno cable breaks. In order to do this,disconnect the cables from the pres-sure switch and circuit board.If a cable has come loose, reconnect it.If there is a cable break, replace thecable.Service instructions VMGFC302 – 37