ASHP & triple glazing

[Joeboy]

Pipework all ok as currently installed diameters?

Moxi

Changing the 22's from loft to sub ground floor.

It's growing arms & legs but only want to do it once...

Triple rads and great big tall ones going in apparently.

She's daeing her dinger!

Rad horse trading second stage commenced, soon...the price.

[Moxi]

So 8kW loss across the whole house on the coldest days of the year?

Does this 8kW also include DHW demand ?

Did they say what flow temperature they had selected ?

Did they take account of you using the SH and WBS on the very coldest of days.

Sorry for all the questions but its interesting to but I find this stuff really interesting and I wonder how they arrive at these core decisions.

I also ask because of late the statement that "you need more rads" seems to be the replacement phrase for the old mantra of "you need bigger pipes" which generally seems to be less and less the case.

There's obviously a balance between CoP / Emitter surface area / flow temp /comfort and I just wondered how your heat engineered arrived at the sweet spot ?

Moxi

[Joeboy]

So 8kW loss across the whole house on the coldest days of the year?
YEP

Does this 8kW also include DHW demand ?
YEP

Did they say what flow temperature they had selected ?
40 degs

Did they take account of you using the SH and WBS on the very coldest of days.
NOPE, they're a bonus. The SH's may well go other than 1 or 2 800W units.

Sorry for all the questions but its interesting to but I find this stuff really interesting and I wonder how they arrive at these core decisions.

I also ask because of late the statement that "you need more rads" seems to be the replacement phrase for the old mantra of "you need bigger pipes" which generally seems to be less and less the case.

There's obviously a balance between CoP / Emitter surface area / flow temp /comfort and I just wondered how your heat engineered arrived at the sweet spot ?

He was a long time measuring up everything including the existing rads and he inputted it all into his desktop and slid it all around last night. He aims for a minimum SCOP of 4.0. I'd say he's put 6 hours in for us already. The penny really did drop yesterday how important a proper detailed heat loss survey and full honesty in the build fabric to the surveyor is critical to achieve a comfortable home and a decent SCOP. Any bullshitting by the owner or guessing by the installer knocks out the bottom level of the pyramid.

Moxi

[AGT]

First dibs on the heaters

[Moxi]

Cheers Jo,

Based on what you said there’s clearly scope to drop one or two rads off the list IF you either want to save some brass (unlikely in this instance) OR you lack space / aesthetics. What you lose on reduced emitter surface area would be made up by WBS or SH. Obviously fitting emitters up to the coldest days means in warmer days your set back is larger and the ASHP runs more efficiently (up to a point)

Sounds like a good day at your place and good results.

Got to say it’s got me itching to get on with things but I know we are short on 4 months of real data at the most critical hearing period so I need to resist temptation. It’s got me wondering though if in my small cottage I’m better off with two air conditioning units (one upstairs and one downstairs for heating and cooling) remove the radiators completely and get a hybrid hot water cylinder just to supply the DHW we like cold bedrooms so heat transfer wouldn’t necessarily be an issue - I will be running the numbers and discussing with my wife see if and how that stacks up against the wet system and ASHP option

Here’s hoping your quote is a pleasant one.
Moxi

[Joeboy]

It has been an interesting day. Homing in on.the ashp quote, horse trading to move existing rads about the house to save a few quid and recycle. Heard back that the 3g cut through arrives tomorrow and dealing with a guy in Inverness for a 40kW Renault Zoe for No1 son to be safer.We go for the Zoe tomorrow morning in the I5.

So far my 25% SIPP tax free portion is I hope being cleverly deployed.

SWMBO.was both a genius and a recalcitrant child today. Does not like change and is currently blowing hot & cold about it all while continuing to come up with great ideas.

I was fascinated to watch the heat calc data being gathered. Especially as the house taken as a whole was built in four stages crossing three different sets of building regs.

As to the A2A HP idea, I absolutely love them and in the right property would have no hesitation. In fact we're having an old compressor type AC changed to an inverter type A2A HP out in Turkey in a couple of weeks. Hoping that will be the last thing king on RE for a wee bit. Slim hope!

[Joeboy]

There's no doubt this saving the planet malarky can be a bit pricey.

Valliant Aerotherm 7kW ASHP
Valliant 200 ltr HPC
Valliant sensocomfort & App gateway
Antifreeze, magnetic filter, pipework upgrade
Wall mounting of heat pump incl access provision(?)
Sparky bits, docs etc

£13,768

Supply & fit 11 Stelrad compact but BIG rads

£5,305

Total price £19,073 before grant

Once i picked myself up off the floor I think im not too far off the 12.5k I seem to remember for the last local install? Add 9 month inflation, a wall mount and i'm ok. The 11 rads (out of existing 14) i've just got to see as essential upgrades and eat the cost with a smile.

[Fintray]

There's no doubt this saving the planet malarky can be a bit pricey.

Valliant Aerotherm 7kW ASHP
Valliant 200 ltr HPC
Valliant sensocomfort & App gateway
Antifreeze, magnetic filter, pipework upgrade
Wall mounting of heat pump incl access provision(?)
Sparky bits, docs etc

£13,768 Ouch! Does that include the monitoring kit? Actually that's probably not a bad price, mine was £13.5k which included the supply of 5 rads but I did the plinth, primary pipework, cabling and put the HWC in position.

Supply & fit 11 Stelrad compact but BIG rads That's probably about 500kg of rads at least

£5,305

Total price £19,073 before grant

Once i picked myself up off the floor I think im not too far off the 12.5k I seem to remember for the last local install? Add 9 month inflation, a wall mount and i'm ok. The 11 rads (out of existing 14) i've just got to see as essential upgrades and eat the cost with a smile.

[Joeboy]

There's no doubt this saving the planet malarky can be a bit pricey.

Valliant Aerotherm 7kW ASHP
Valliant 200 ltr HPC
Valliant sensocomfort & App gateway
Antifreeze, magnetic filter, pipework upgrade
Wall mounting of heat pump incl access provision(?)
Sparky bits, docs etc

£13,768 Ouch! Does that include the monitoring kit? Actually that's probably not a bad price, mine was £13.5k which included the supply of 5 rads but I did the plinth, primary pipework, cabling and put the HWC in position.

Supply & fit 11 Stelrad compact but BIG rads That's probably about 500kg of rads at least

£5,305

Total price £19,073 before grant

Once i picked myself up off the floor I think im not too far off the 12.5k I seem to remember for the last local install? Add 9 month inflation, a wall mount and i'm ok. The 11 rads (out of existing 14) i've just got to see as essential upgrades and eat the cost with a smile.

Thanks Iain, they're sending me rad details so I can see what's what. The relentless inflation too. Also the HWC is going in through the roof tiles. The powerflush etc. If it all came in incl the 3g I'd be 2 grand over my original guess after grant. I'm getting an awful lot of bang for that buck. I'm happy, well not happy exactly.

As to the monitoring kit? I.hope so, I'm only doing this to keep us both entertained across Winters.

[Fintray]

As to the monitoring kit? I.hope so, I'm only doing this to keep us both entertained across Winters.

It's handy to see the results of any changes you make to the heat curve etc and how the system performs over time and it'll definitely keep you entertained.