Ground Source Heat Pumps

beardymarrow

I bet. It was a shot worth taking. Out of interest how much did the caps cost? 
Thank you for being a guinea pig 😂

lstevensuk

About £40 - so just the £810 saving then Happy to be a guinea pig any time

lstevensuk

beardymarrow said:

lstevensuk said:

beardymarrow said:

lstevensuk said:

beardymarrow said:

lstevensuk said:

Random question - with the IVT heat pump is it possible to mix both radiators and UFH. Currently we have radiators throughout the house. We are building a new extension and wondered if I could have UFH in just the new part?

Yes, absolutely. We have that. I imagine it's fairly common. You need to fit a mix valve operated from the GSHP controller and separate temperature sensor so that the UFH operates at a lower temperature (curve slope is lower). The user manual shows where to fit the valve. 

Would that mean running new pipes from the GSHP to the new areas? That would be a pain as it's in a barn not the house and fair amount of tarmac in between

No, but you'd need to run the wire from the mix valve and the temperature sensor to have them controlled by the GSHP controller. In your situation I'd just have a manual mix valve 

So literally a mixer type valve that I adjust couple of times a year till I'm happy with the temp? And this connects to my existing radiator pipe work. I will ask my plumber just want to get my head around the concept first.

Yeah, exactly. It just blends a portion of the colder water returning from the ufh with the hotter flow from the GSHP so that the ufh runs cooler than the rads. 

Now I'm up and running just looking at kits. had a quote from this company. just checking I'm heading down the right route getting a full kit?

https://underfloorheating1.co.uk/product/underfloor-heating-premium-2-port-kit-system

beardymarrow

lstevensuk said:

beardymarrow said:

lstevensuk said:

beardymarrow said:

lstevensuk said:

beardymarrow said:

lstevensuk said:

Random question - with the IVT heat pump is it possible to mix both radiators and UFH. Currently we have radiators throughout the house. We are building a new extension and wondered if I could have UFH in just the new part?

Yes, absolutely. We have that. I imagine it's fairly common. You need to fit a mix valve operated from the GSHP controller and separate temperature sensor so that the UFH operates at a lower temperature (curve slope is lower). The user manual shows where to fit the valve. 

Would that mean running new pipes from the GSHP to the new areas? That would be a pain as it's in a barn not the house and fair amount of tarmac in between

No, but you'd need to run the wire from the mix valve and the temperature sensor to have them controlled by the GSHP controller. In your situation I'd just have a manual mix valve 

So literally a mixer type valve that I adjust couple of times a year till I'm happy with the temp? And this connects to my existing radiator pipe work. I will ask my plumber just want to get my head around the concept first.

Yeah, exactly. It just blends a portion of the colder water returning from the ufh with the hotter flow from the GSHP so that the ufh runs cooler than the rads. 

Now I'm up and running just looking at kits. had a quote from this company. just checking I'm heading down the right route getting a full kit?

https://underfloorheating1.co.uk/product/underfloor-heating-premium-2-port-kit-system

Hi,
That looks about right, but I'm not a plumber, so I'd rely on their advice. Was your GSHP sized for this additional load?
You might also want some sort of thermostatic control over one of the zones? As an example, we have a thermostat linked to only one of the zones on our 4 zone UFH as it's in a place that gets a lot of direct sunlight so we shut that zone off if the floor temp rises due to the sun heating it.
Or, a thermostatic valve controlling the mixing if both zones need automatically controlling.
I'd recommend getting your plumber to spec what is needed to be honest, as they'll have much more experience. I only know my setup :-)

lstevensuk

Hi - Yes have checked with plumber now nd good point on the thermostatic controls.

How do I check my GSHP Size? I'm pretty sure it's an IVT HT+ . I want to say 9kw...

beardymarrow

lstevensuk said:

Hi - Yes have checked with plumber now nd good point on the thermostatic controls.

How do I check my GSHP Size? I'm pretty sure it's an IVT HT+ . I want to say 9kw...

There'll be a sticker on top of the unit that says what it is, but whether it's already running at its limit or has plenty of headroom would depend on the existing design load. If it's under spec for the total you'll end up using a lot of expensive immersion (additional) heat.

lstevensuk

Ok thanks will check this evening. Have no idea on original spec - it was installed in 2010 by previous owner. From a few calculators online it suggests I need anywhere between 6kw and 13kw. Any recommendations on a decent calcualtor?

lstevensuk

Does anyone recognise the model from this? IVT HT + ...

It was actually installed in 2008 - what's the expected lifespan of these?

beardymarrow

lstevensuk said:

Does anyone recognise the model from this? IVT HT + ...

It was actually installed in 2008 - what's the expected lifespan of these?

Hi,
That's an HT+ C6. C means it's got a hot water cylinder built in and 6 is the kW output rating (excluding the 9kW immersion).

For what it's worth, we have a 9kW model and our EPC says we need ~19600 kWh per year for space heating and ~2500 kWh per year for water heating (so ~22100 total). I don't know how, or even if, the EPC usage estimate relates to the GSHP sizing as GSHP sizing is witchcraft to me. I also don't know if the EPC ratings are reliable either.

I'm sorry I can't be of much help on this aspect. It's outside my area of knowledge.

lstevensuk

I found this detail in my UFH heating quote which might help somone in the future:

Boiler sizing – For UFH only – not including radiators and/or hot water demand, we recommend 0.070kW/m² for new build properties and any refurbishment with insulation levels equivalent or more than current building regulations. For properties where insulation levels do not meet current building regulations, we recommend at least 0.085kW/m²