instantaneous heat pump

[john4703]

I’m not sure which forum to put this in. I look after a church and there was an almost useless water heater in the kitchen. It started to leak and I’ve removed it. (It was almost useless as it only heater 12 litres of water)

I want to fit an electric instantaneous water heater to supply two sinks in the kitchen. An instantaneous heater would be best as demand varies a lot, some days there is loads of washing up and other days jut one or two mugs. A storage heater would be wasteful.

I am wondering if there is any instantaneous water heater that uses a heat pump as this should be a lot cheaper to run.

 

[cdbe]

Heat pump is a non starter. In our scout hut we fitted a 10kw instantaneous heater - just the job - enough hot water for washing up etc - for 5 minutes or 5 hours if we needed it. Not sure if enough for two sinks at same time.

 

[ericmark]

I have often wondered why we don't have oil or gas fired heat pumps if they are so good, but in real terms there is a limit to how hot a heat pump can raise water above ambient temperature, and as one aims for higher temperatures so the gains are reduced.

They also cost more, and as with any moving machinery have a limited life. So the gains are not enough to be worth while.

 

[Johntheo5]

The first heat pumps (refrigeration) that I remember was in the country, no electricity, in the 1950s, adsorbtion chillers powerd by a paraffin heater so also wonder why no mention of heat pumps using that principle as they should have .much the same COP as conventional heat pumps with only a third of the running costs until we all get low cost electricity, of course!!.

 

[old duffer]

 

[MNW67]

I am wondering if there is any instantaneous water heater that uses a heat pump as this should be a lot cheaper to run.

I don't think there is such a thing. The upfront cost would be huge for a heat pump with enough output to do instant hot water.