| Leakage |
| 1. Close all valves on the plumbing bracket under the unit and the mains cold water feed. |
| 2. Contact your engineer. |
| Central Heating Circuit does not heat |
| 1. Make sure the valves on the plumbing bracket are open (handle in vertical position). |
| 2. Check radiator valves are open and calling for heat. |
| 3. Check the programmer is set to ON, and calling for heat. |
| 4. Set the room thermostat higher. |
| 5. Problem solved? If not, contact your engineer. |
| No Domestic Hot Water |
| 1. Check that the mains cold water valve is open. If not, open the main valve. |
| 2. Problem solved? If not, contact your engineer. |
| Water is not hot |
| 1. Ensure that all valves on the plumbing bracket under the unit and the main valve are open. |
| 2. Make sure the power cord is plugged in and turned on. If in doubt contact an electrician. |
| 3. Problem solved? If not, contact your engineer. |
| Sound |
| It is normal that the HIU makes noise when hot water or heating are active. If the HIU starts to make any loud or disturbing noises, contact your installer. |
The MECH HIU documentation
Table: MECH Basic Troubleshooting
Converted from the Heatweb wiki article “Table: MECH Basic Troubleshooting”, last edited 2016-02-02. Under review for the new site.
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