ASHP or Oil Boiler

[Marvin]

In the long term I like the idea of generating some of my own power for our ASHP. Something I cannot do with a gas boiler...

 

I know the set up cost is a lot but with the PV being used for the EV and the house as well I'm happy to go there.

 

 

[patp]

21 hours ago, Marvin said:

In the long term I like the idea of generating some of my own power for our ASHP. Something I cannot do with a gas boiler...

 

I know the set up cost is a lot but with the PV being used for the EV and the house as well I'm happy to go there.

I think that this is the way to go with ASHP's. We certainly have done this. I think that building regs need to change to make solar panels compulsory with an ASHP.

 

 

[patp]

Building regs need to change to make solar or wind etc compulsory with ASHP installations.

[PeterW]

12 minutes ago, patp said:

Building regs need to change to make solar or wind etc compulsory with ASHP installations.

Solar yes, small scale wind is not viable for domestic installation. 

[ValleyBoy1958]

On 22/08/2021 at 19:21, SteamyTea said:

That is about 13,400 kWh/year.

If you use 80% of that in 4 months (winter), that works out at ~90 kWh/day.  That could be satisfied with a 5 kW heat pump, but one would probably have to go to an 8 kW to be on the safe side.

That may change the installation cost.

 

 

Thanks for your reply. Is that the usual rule of thumb i.e. 80% of fuel used during the 4 winter months? Your response has prompted me to look at the monthly pellet consumption figures. I have kept a daily usage record since I had the boiler 7 years ago, so on a wet afternoon I could plug the data into spreadsheet and see what I find! BTW we have solar thermal which provides all our DHW from late May to early September which helps.

Edited August 23, 2021 by ValleyBoy1958

[SteamyTea]

7 hours ago, ValleyBoy1958 said:

Is that the usual rule of thumb i.e. 80% of fuel used during the 4 winter months

It is about what I use, though it is very variable.

If you have the data, apart from the plugging it in, and finding the daily temperatures, it is a fairly easy thing to do.

[canalsiderenovation]

On 23/08/2021 at 23:23, ValleyBoy1958 said:

 

Thanks for your reply. Is that the usual rule of thumb i.e. 80% of fuel used during the 4 winter months? Your response has prompted me to look at the monthly pellet consumption figures. I have kept a daily usage record since I had the boiler 7 years ago, so on a wet afternoon I could plug the data into spreadsheet and see what I find! BTW we have solar thermal which provides all our DHW from late May to early September which helps.

 

We used a lot in winter, granted we didn't have our external insulation and we were we doing a lot of getting use to our heat pump but over the past few months our consumption has been far less. We had insulation and render sorted in July and our heating has been off since June and our water has been done by the solar immersion thingy aside from a week in August so far when the solar hasn't done enough for the hot water we had our heat pump on. I suspect by the end of Sept we will need to have the heat pump doing our heating and hot water again as the solar will be minimal and we will need heating soon.

 

March 992 (no EWI insulation/render)
April 732.7 (no EWI insulation/render)
May 494.8 (no EWI insulation/render)
June 130.4 (no EWI insulation/render)
July 113.4
August (as it stands today) 132.7

 

I suspect our consumption Oct-March will tend to be about 700-900 units a month.

[richo106]

Thanks for all the comments, we have had good discussions with the builder and have agree to basically knock the house down. This includes filling in the suspended ground floor and installing a new concrete slab. I thought this would be ideal for the WET UFH we want. 

 

Could some one offer some guidance on what thickness of insulation is needed in the floor for the UFH to sit on and what would the make up/thickness of the floor would be so me and builder are on the same page.

 

This project is hoping to start late 22 early 23 all being well

 

I have been persuaded by the local plumbing firm to install ASHP (well get quote from them for a full house system)

 

What would people recommend upstairs? I was thinking UFH in the main bathroom and en-suite. What about in the bedrooms? Would radiators (spec to correct temps etc) work better than UFH under carpet?

 

People on the forum mention air tightness/insulation for use of ASHP...where are the main areas of insulation/air tightness that needs to be considered?

 

Thanks in advance