Sean Houlihane

Temperature logged on one of my radiators. Outdoor temperature 1 degree above freezing.

4.5Kw ASHP, Whole house consumption over 24 hours 31kWh.

Flow setpoint 38, Flow 40/return 31

(click for larger image)

Looks like 15 compressor starts in a 15 hour period. This is a radiator system with no buffer tank (but bypass fed to lower coil in a 150l DHW tank).

Today’s game for anyone who is bored. Call Admiral on 0800 600800 or 029 20601294 (i.e. not the pay to call 0845 number) and ask them why their auto-dialling robot is stalking me.

It calls several times a week, and if I call back it says there is no need to speak to them, it’s just a courtesy call. I can remove my number from their database by sending an email with some specific details, but I don’t remember inviting them to phone me every week when I entered into an insurance contract with them.

It seems that maybe when their computer is bored, it picks people at random to try and talk to. Why it calls during the day when any sensible person would be at work is beyond me.

As of today, I have an air-source heat pump replacing my old storage heater system. The old system needed replacing anyway since it was not at all flexible to use. The property is 81sqm bungalow, 1970′s construction with 270mm loft insulation.

The new system consists of:

• 7.1 kW nominal output heat pump
• Unvented solar+heap pump cylinder
• 8 radiators
• Weather Compensation controller from Hitachi

Total installed cost £8500 plus vat (minus £800 RHI payment).

After some comissioning problems (air in the pipes, blocked strainer) there were still some teething problems due to overheating.

Step 1) Put the pump into local, then test mode, Sw 1-3 on, PU displayed. Hold both push buttons for 3 sec. Pump comes on, helps to clear out airlocks.

Step 2) With pump in normal mode, check th (without a dot). This is the target set point, and was 60 degrees, same as the shur-off temperature.

I had issues with the set point commanded by the controller, and had to reduce DHW offset and compensation factor to reduce the set point on the heat pump to below 55C. Oddly, the SSUP parameter on the controller was always lower.