Can you advise what the fault \ problem you with your heat pump, in addition to the make and model.
Do you have a model or part number for the heat pump?
Good afternoon Mary,
Further to our telephone call, I have phoned some of the local engineers in your area. Since labour cost in London is significantly higher it may still be worth repairing your shower.
I would recommend you use Plumb London on(###) ###-####7135, they can normally come out next day and for £50 they will come out give you a quote for a new shower which is likely to be around £500 includes parts and labour.
An equivalent power shower should would be 9KW rating or above, you can find a range of power showers at a reasonable price here.
When speaking to the plumber they advised an alternative is to do a repair which would work out half price. The cost to come out, diagnose the fault and order the part would be £54, your then looking at around a further £150 to supply and replace the part.
Based on the significant difference in cost, I would recomend with repairing the shower in this instance.