Another ashp/electricity usage question

[Roger440]

36 minutes ago, Thedreamer said:

 

I've adopted a multi input approach. Use an exhaust air source heat pump for my domestic water and a wood stove for my heating. 

 

I have never been convinced by large external air source heat pumps, for the average family they are expensive to install and run. Worst of all they become less efficient when you need them most.

 

 

Didnt know there was such a thing. Seems quite logical when you think about it. Why isnt everyone doing it?

[ProDave]

10 minutes ago, Roger440 said:

 

Didnt know there was such a thing. Seems quite logical when you think about it. Why isnt everyone doing it?

I was put off an EAHP by several reports on a previous forum before buildhub started, of a lot of failures of what at the time seemed to be the most popular make of EAHP.

 

I have not seen such reports for a while so I assume any issues were solved.

[Thedreamer]

10 minutes ago, Roger440 said:

 

Didnt know there was such a thing. Seems quite logical when you think about it. Why isnt everyone doing it?

 

Not sure why more people don't use these systems. All I can say it works for us.

 

My energy bills all in with the £400 rebate will be a couple of quid from October to March.

[jamieled]

@Thedreamerhedreamer do you know how different your MVHR ducting design is to say, a standard MVHR design, in order to accommodate the EASHP?

[Thedreamer]

It consists of three extraction points, one in our ensuite, bathroom and utility these then run into the heat pump/fan on top of the cylinder it then has an outlet from the tank to blow cold air to the outside. 

 

Overall the COP is quite efficient and consistent in turning the air from the house into hot water. I admit it must be taking energy from the envelope of my house, but I have never found the temperature to drop much. Whatever is disappearing up the duct into the system is being replaced by either solar gains on good days or the trug of home grown logs and sticks I burn in the evening in the winter.

 

Not sure how much energy is in a seasoned split spruce log or a branch from a birch/alder tree but been doing this now for three winters and I have spent no more than £5 to £10 on heating the house since June 2020.