Heat pump on a day/night meter

dellas1979

Hi guys,

101 here on understanding this, so bear with me.

I've to contact the ESB tomo to let them know what sort of meter I want.

I have a heat pump A2W. Thermostat in each zone.

The electrician is suggesting a day/night meter. He says house is insulated very very well. So little heat loss.

I've been talking to him about it, but for the life of me, cant get exactly to the question (or answer) I need.

Maybe questions are being fuelled by hearing horror stories about heat pumps and costs to run.

- On the day/night meter, the night time tariff is cheaper. He is saying the water/heating could come on for couple of hours a night. I think what am understanding is that if it comes on, because of insulation, the house will stay warm. If I heated the water for a couple hours a night, it would stay hot.

- Am more worried about using appliances during the day. Washing/drying machine / dishwasher / TV. Particularly for washing and drying machine, how could this work at night? (I mean, am not going to put on a wash on at 11pm when night time rate comes on, and get up and put in drying machine at 3am).

How does it all work out? Its a 100 square meter house (3 bed/bathroom) with UFH/thermostat contolled/A2W heat pump/7 inches of insulation.

If I felt I made a mistake on the day/night, I suppose I could revert? I talked to Electric Ireland, and they have a tariff for day/night.

Any advice, would be very welcome.

Calahonda52

Have u a buffer tank with the UFH?

where is the 7" of insulation?
What was the result of the airtightness test?

dellas1979

During the summer months the heat pump won't run as the temperature outside is high so the backup heater (immersion) built into the heat pump will heat the water (is this what you mean by buffer tank?)

Provisionally testing, the airtightness test was 1.6 (am being told it will come down another bit with plasterboarding and flooring in). It will be retested again.

The outside walls were pumped (no plasterboarding yet - when I walk in, I can see the insulation bulging (well, not bulging, but you can tell insulation packed in there).

How would washing machines etc run on a day/night? Has anyone else ran their system like this?

dubrov

I am assuming it is a new build.

The heat pump will use more power at night as it is colder.
All modern dishwashers/washing machines have a delay mode. You just set them to run in the night.
Electric cars are on the horizon as well and you can charge at night.

Day/Night makes sense as long as you are willing to put in a basic amount of work (i.e. click 2 buttons to delay a dishwasher run 6 hours).
IF you don't tend to do that, the 24hr rate might make more sense.