@alec-morrow 

Alec , does this mean that the manufacturer is actually mandating an installation method that's sub-optimal for their own equipment?

Are there makes, other than Grant, available on the UK market which are designed and specified to be installed in the most optimal way?

Mike

@mike-patrick all equipment supllied complies with U.K. regulations, but U.K. regulations do not promote optimal equipment, and that is a problem for many people with heat pumps.

the key question to ask the manufacturer is: 

”will the indoor controller proposed by my supplier compensate the flow temperature in tandem with the out door sensor?”

do nt ask the controls supplier or manufacturer  but the installer may have the knowledge about compensation or modulating controls

its the heat pump that is lead slave to the Controller

UK heating controls do not compensate flow temperatures

Posted by: @kev-m

@webcmg 

I'm sure @derek-m will help you with the technical details. However, although my house is smaller than yours at 160m2, its heat requirements are similar because it's older.  My average in December is 25.5kWh/day to heat the whole house to 21C for 19 hours/day.   As long as the design of the system is sound you should be able to improve on 70kWh/day.  

If the EPC is correct, your heating requirements are c. 15000kWh/year.  You should normally need 15% of that in December, say 2300kWh.  Even at a COP of 2.3, that's 1000kWh/month consumed; a lot less than you're using. 

A question; how much hot water do you use?

   

@derek-m do you have a typical % heating/dwh usage for each month? Would be helpful to do some projected costs for the year based on Dec/Jan usage. Thanks

Posted by: @derek-m

Hi @webcmg 

Check to see if any of the valves are partially closed on any of the radiators.

Check that your water pump is producing adequate pressure and flow to get the water up to the radiators. Try measuring the temperature of your radiators and then shutdown your UFH so that all the flow is going to the radiators. If the temperature of the radiators starts to increase then you have a pressure or flow problem. Try increasing the pump speed.

@derek-m a Vaillant engineer came out today. We've reduced the speed of the UFH pumps and left the radiator pump on a faster setting. We think the bypass may be active on the RAD flow too and I've identified some uninsulated pipes which could be significantly impacting the efficiency. We're getting these things sorted on Monday and fingers crossed there will be an improvement in upstairs comfort levels and energy usage... will keep you posted. Thanks again for your help.

Hi @webcmg 

The heating demand will be dependent upon the heat loss of your home, the indoor temperature and the outdoor temperature. The energy required to produce hot water will depend upon the size and heat loss of your cylinder and of course the hot water usage.

So to answer your question, there is no average usage as such, it will vary from household to household. You could look for similarities with of forum members and compare notes.

@derek-m 

I thought @webcmg was looking for the numbers split the heating total over the year up and said you used 15% in Dec, 18% in Jan, 5% Oct, 0% in July, etc.  I couldn't find that.   

Posted by: @kev-m

@derek-m 

I thought @webcmg was looking for the numbers split the heating total over the year up and said you used 15% in Dec, 18% in Jan, 5% Oct, 0% in July, etc.  I couldn't find that.   

Hi Kev,

I remember someone posting some details about average use in December being 15% of annual total, but it wasn't me, and I don't know where it came from.

Posted by: @kev-m

@derek-m 

I thought @webcmg was looking for the numbers split the heating total over the year up and said you used 15% in Dec, 18% in Jan, 5% Oct, 0% in July, etc.  I couldn't find that.   

@kev-m yes, that's exactly what I am looking for,  I've searched around online but can't find this info.

I think it was maybe @batalto

Is this what you were looking for?

Posted by: @batalto

Is this what you were looking for?

Run cost estimation per month of heat pump
Month	% energy used/ month
January	19%
February	17%
March	12%
April	7%
May	4%
June	2%
July	1%
August	1%
September	4%
October	6%
November	12%
December	15%

Yes, thank you. This is extremely helpful.

Does anyone happen to know the current month energy consumption update interval for the 700/6 controller?  It certainly isn't realtime (no idea why not!) and I have a significant variation in usage at the meter vs usage at the controller. If I can figure out when the controller updates I can rule out something else using so much energy.

Thanks,
Chris