The MECH HIU documentation

Table: MECH Basic Troubleshooting

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.

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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