Fault code F28 / High Pressure fault means that the heat pump controller is detecting high refrigerant pressure (not water pressure) and is stopping operation to protect itself.
• Check that any isolation valves on the water pipes on the rear of the heat pump or around the hot water cylinder have not been closed by accident.
• Bleed any air out of the radiators or heating circuit where possible, If you can hear gurgling or wooshing water noises when the circulation pumps run, there is likely to be air trapped in the pipework which will slow the flow of water around the property. This may require installer to reattend.
• If you know where the heating circuit filling loop is located and the pressure gauge for your heating circuit, check the pressure of the water in the heating circuit. It should be around 1.0 to 1.5 Bar typically. It can be topped up by slowly opening the filling loop whilst watching the pressure gauge, then closing the filling valve once the pressure reads just over 1.0 Bar. If the system pressure keeps dropping, there could be a leak in the pipework which needs to be investigated by your installer or a service engineer.
• Try lowering the heating water temperature by pressing the - button to lower the heating curve. On a touch screen control, tap on the House icon on the left hand side of the screen, then tap on "Home" tile and the heating curve can be lowered by a couple of degrees.
• Power the heat pump off at the mains for 30 mins, then switch back on and see if the issue has been resolved.
• If there is an inline strainer or mag filter, is it clean of any debris.
If the issue is still reoccurring your installer may be required to reattend or service visit may be required. See below link for additional help.
Require additional help? Please follow link below
https://glendimplexservice.freshdesk.com/a/solutions/articles/79000136321
Applicable to models:
System S, System S6, System S10, LIA 0608HWCF MS , LIA 0911HWCF MS, LI 2M, LI 8AS, LI 8ASL, LI 8AS SAL, LI 8MS, LI 8MSR, LI 9AS, LI 9ASH, LI 9AS SAL, LI 9TE, LI 9TEL, LI 9TES, LI 9TU, LI 11AS, LI 11ASH, LI 11ASR, LI 11AS SAL, LI 11ME, LI 11MER, LI 11MS, LI 11MSR, LI 11TE, LI 11TEL, LI 11TER+, LI 11TES, LI 12TU, LI 15TE, LI 16AS, LI 16ASH, LI 16ASR, LI 16AS SAL, LI 16TE, LI 16TEL, LI 16TER+, LI 16TES, LI 20AS, LI 20AS SAL, LI 20TE, LI 20TEL, LI 20TES, LI 22HS, LI 24AS, LI 24AS SAL, LI 24TE, LI 24TEL, LI 24TES, LI 26HS, LI 28AS, LI 28AS SAL, LI 28TE, LI 28TEL, LI 28TES, LI 40AS, LIH 10TE, LIH 22TE, LIH 26TE, LIK 8ME, LIK 8MER, LIK 8TE, LIK 8TEL, LIK 8TES, LIK 12TU, LIKI 14TE, LA 6MR, LA 6S-TU, LA 6S-TUR, LA 6TU, LA 8AS, LA 8MR, LA 8PMS, LA 9K, LA 9PS, LA 9S-TU, LA 9S-TUR, LA 9TU, LA 10MR, LA 11AS, LA 11ASR, LA 11K, LA 11MAS, LA 11MS, LA 11MSR, LA 11PS, LA 11TAS, LA 12PS, LA 12S-TU, LA 12S-TUR, LA 12TR, LA 12TU, LA 13K, LA 14PMS, LA 15K, LA 16AS, LA 16ASR, LA 16MAS, LA 16MS, LA 16TAS, LA 16TR, LA 17PS, LA 17TU, LA 18I-MU, LA 18PS, LA 18S-TU, LA 18S-TUR, LA 20AS, LA 22HS, LA 22PS, LA 22TBS, LA 24AS, LA 25TU, LA 25TU-2, LA 26HS, LA 26PS, LA 28AS, LA 28TBS, LA 33TBS, LA 35TUR+, LA 40AS, LA 40TU, LA 40TU-2, LA 60TU, LA 60TU-2, LA 60TUR+, LA60STU, LA60STUR, LAC 12TR, LAC 16TR, LAJ 11MUR, LAJ 16MUR, LAJ 60TUR+, LAK 10M, LAK 10MR, System M, LAK 3IMR, LAK 6IMR, LAK 9IMR, LAK 14IMR, LAK 14ITR, LAW 6IMR, LAW 9IMR, LAW 14IMR, LAW 14ITR, LIA 7IM, LIA 9IM, LIA 12IM, LIA 14IM, LIA 16IM,LSA60TUR,LSA60TPR,LSA60TPR2,LSA100TUR, SI 5BS, SI 5CS, SI 5ME, SI 5MER, SI 5MS, SI 5MSR, SI 5TE, SI 5US, SI 5USR, SI 6TU, SI 7BS, SI 7CS, SI 7KS, SI 7ME, SI 7MER, SI 7MS, SI 7MSR, SI 7TE, SI 7US, SI 7USR, SI 8MR, SI 8TU, SI 9BS, SI 9CS, SI 9KS, SI 9ME, SI 9MER, SI 9MS, SI 9MSR, SI 9TE, SI 9US, SI 9USR, SI 10MER, SI 10MR, SI 11BS, SI 11CS, SI 11KMS, SI 11KS, SI 11ME, SI 11MER, SI 11MS, SI 11MSR, SI 11TE, SI 11TU, SI 11US, SI 11USR, SI 12TR, SI 14BS, SI 14CS, SI 14KS, SI 14ME, SI 14MS, SI 14TE, SI 14TR, SI 14TU, SI 14US, SI 14USR, SI 16KMS, SI 16TR, SI 17BS, SI 17CS, SI 17TE, SI 18TU, SI 20TR, SI 21CS, SI 21TE, SI 22TU, SI 24TE, SI 26TU, SI 30CS, SI 30TE, SI 30TER+, SI 35TU, SI 35TUR, SI 37TE, SI 40HS, SI 50TE, SI 50TU, SI 50TUR, SI 50ZS, SI 70CS, SI 70TUR, SI 75TE, SI 75TER+, SI 75TU, SI 75ZS, SI 75ZSR, SI 90TU, SI 100TE, SI 100ZS, SI 130TE, SI 130TU, SI 130TUR+, SI 130ZS, SIH 6ME, SIH 6TE, SIH 9ME, SIH 9TE, SIH 11ME, SIH 11TE, SIH 20TE, SIH 40TE, SIH 90TU, SIHJ 90TU, SIJ 10MER, SIJ 75TER+, SIJ 130TUR+, SIK 6TES, SIK 7TE, SIK 7TE-2, SIK 8TES, SIK 9TE, SIK 9TE-2, SIK 11ME, SIK 11TE, SIK 11TE-2, SIK 11TES, SIK 14TE, SIK 14TE-2, SIK 14TES, SIK 16ME, SIKH 6TE, SIKH 9ME, SIKH 9TE, SIW 6MU, SIW 6TES, SIW 6TU, SIW 8MU, SIW 8TES, SIW 8TU , SIW 11MU, SIW 11TES, SIW 11TU, WI 9CS, WI 9ME, WI 9TE, WI 10TU, WI 14CS, WI 14ME, WI 14TE, WI 14TU, WI 18CS, WI 18TE, WI 18TU, WI 22CS, WI 22TE, WI 22TU, WI 27CS, WI 27TE, WI 35TU, WI 40CS, WI 45TU, WI 50TU, WI 65TU, WI 90CS, WI 95TU, WI 100TU, WI 120TU, WI 140TUR+, WI 180TU, WIH 120TU, WPM 2006plus (H), WPM 2006plus (L), WPM 2006R, WPM ACU, WPM Basetec, WPM Econ5, WPM Econ5Plus, WPM Econ5S, WPM EconPlus, WPM EconPlus-E, WPM Econ SOL, WPMJ ACU, WPMJ EconPlus, WPMJ EconPlus-MD, WPM PK, RTCFM, RTCSM
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