UPDATED: Air Source Heat Pumps/Air Con - Full Info & Guide, is it cheaper to run than mains gas?

Andy_WSM

Swipe wrote: »

I'm considering an ASHP to replace an old broken GEC Nightstore wet electric boiler system. I have all my existing radiators in place ready for reuse but I'm wondering if I should just go for the wall mounted air units in the hallway and one or two rooms instead, or does it make sense to go with the water system? I'm happy to stay with my economy 7 immersion heater for my DHW as I am an early riser and just switch it on for the last hour or so of the E7 cycle on the days I require hot water (I live alone). It is an insulated 3 bed bungalow so I'm wondering if I could manage with a 5kw unit or if I'd need to 8kw or the 11kw? Are there any grants available to help with installation costs for ASHPs yet?

Edited to add: I will be using my multifuel stove for the heating in my main room so the ASHP is only needed to maintain a temp of 15C - 17C in all other rooms, rather than primary heating source.

If you only require low level heating then the 5KW will be sufficient (especially if you are making no hot water demands of it) if you are happy to leave it running for longer periods. If you want quick heat then you will need a bigger unit.
I work from home, so 24/7 heat suits me, so I don't have any issue with the unit running when it needs to.

paceinternet

I would suggest at least measuring the sq m of the rooms you want to heat, and then calculate the heat requirements using some basic watt per sq m numbers. Say 80 w/sqm, although many other factors could mean this should go up or down.
You should also review what kwh you will be using in future during day and night, as E7 may not be the right tariff if the heat pump is mostly working during non E7 hours.
If it is a saving to go to a std tariff, you may want to use the heat pump to do some of the hot water, with the immersion heater as a back up.

Swipe

Thanks for the replies. For the sake of an extra £1k or so, I will probably go with the 12kw Trianco unit and connect it to my radiator system, that way I can cover all rooms.

Cardew

Swipe wrote: »

Thanks for the replies. For the sake of an extra £1k or so, I will probably go with the 12kw Trianco unit and connect it to my radiator system, that way I can cover all rooms.

Bear in mind though that your existing radiators will almost certainly not be large enough.

Swipe

The radiators are pretty big as they were connected to an electric boiler running on E7 so they appear to have been upsized for that system. If I can maintain 15C I'll be happy as I have the log burner for the sitting room.

richardc1983

Swipe wrote: »

I'm considering an ASHP to replace an old broken GEC Nightstore wet electric boiler system. I have all my existing radiators in place ready for reuse but I'm wondering if I should just go for the wall mounted air units in the hallway and one or two rooms instead, or does it make sense to go with the water system? I'm happy to stay with my economy 7 immersion heater for my DHW as I am an early riser and just switch it on for the last hour or so of the E7 cycle on the days I require hot water (I live alone). It is an insulated 3 bed bungalow so I'm wondering if I could manage with a 5kw unit or if I'd need to 8kw or the 11kw? Are there any grants available to help with installation costs for ASHPs yet?

Edited to add: I will be using my multifuel stove for the heating in my main room so the ASHP is only needed to maintain a temp of 15C - 17C in all other rooms, rather than primary heating source.

Go for air units, you will benefit from cooling in summer then.

Swipe

Thank you for the responses. I have decided to go for the air to air unit and keep my DHW on E7. I'm obtaining quotes for the Panasonic energy saver heat pump and the Worcester Greensource air to air heat pump. Could anyone recommend any other air to air units that might be worth researching?

Hermann

Mitsubishi ecodans are worth a look too.

Cardew

Hermann wrote: »

Mitsubishi ecodans are worth a look too.

Do they have an Ecodan air to air system?

The ones I have seen are air to water.

richardc1983

Swipe wrote: »

Thank you for the responses. I have decided to go for the air to air unit and keep my DHW on E7. I'm obtaining quotes for the Panasonic energy saver heat pump and the Worcester Greensource air to air heat pump. Could anyone recommend any other air to air units that might be worth researching?

By your post I assume your keeping your hot water heating the same but your looking to have air conditioning that will provide the heating?

The best systems to go for are Mitsubishi electric.

here is a link to a very good system for heating, the heat also blows out of a flap at the bottom of the unit to ensure cosy warm feet!

http://www.bdt.co.nz/aircon/product.aspx?item=68954I

This product can also be found on the Mitsubishi Uk website however I couldnt paste a direct link in.