If you have no heat or hot water here are some simple checks you can do before calling out an engineer. Step 1 – Look for causes. Are the appliances turned on? If you have an isolation switch on your fuse box, is it set to on? Pre-payment customers – check that your credit has not run out. Step 2 – Check the thermostat is turned up and clock timer is set Step 3 – Check your boiler appliance controls Step 4 – Examine the pressure gauge to see if it’s at approximately 1 bar. Step 5 – If you have a pilot light, is it turned on? If you still have no heat or hot water then we may need to send out an engineer.