We should have installed air conditioning… now what?

[Dave Jones]

2 minutes ago, Adsibob said:

What would I need to do that? The lowest tempera setting on my UFH manifolds is 35C.

 

heat pump in reverse.

[SteamyTea]

26 minutes ago, Dave Jones said:

send the cold water through the slab UFH as well.

That is a good idea.

  

1 minute ago, Dave Jones said:

heat pump in reverse.

Whether heating or cooling, they are still heat engines.  The devil is in the demon.

 

Most have settings that can be changed to deliver either hot or cold.

[Wil]

4 hours ago, Adsibob said:

What would I need to do that? The lowest tempera setting on my UFH manifolds is 35C.

 

If that’s the mixing valve, then sending it cold water when it’s expecting hot just means it will fully open and not mix any of the return from the UFH manifold. This is fine as the higher temp return water will just go back to your ASHP/ chiller.

 

If it’s the lowest temp setting to get the manifold circulation pump to engage, that would be strange and definitely a problem for this idea.

 

If you have room stats, you may need to set them excessively high in order to get those zones to open if the temperature in the zone you’re trying to cool is already high.

[joth]

4 hours ago, Adsibob said:

What would I need to do that? The lowest tempera setting on my UFH manifolds is 35C.

You said above you don't have a heat pump?? So first step would be getting one of those. For cooling I'd recommend a2a which really starts back at the top of this thread, doesn't it. 

[Adsibob]

2 hours ago, joth said:

You said above you don't have a heat pump?? So first step would be getting one of those. For cooling I'd recommend a2a which really starts back at the top of this thread, doesn't it. 

I won't be installing a heat pump, having investigated these options at length at the time of design and concluded that the market was crazy. It was much cheaper, and less hassle, to get a highly efficient gas boiler, than go through the process of:

1. getting planning permission to install a more expensive air source heat pump, work out where to put the external unit so that it wouldn't bother us or the neighbours
2. borrowing money to pay for an even more expensive one of these: https://www.ochsner.com/en/ochsner-products/air-source-heat-pump/ (quoted to me at the time as costing something like £15k).

There are space constraints in my property that just make it non-feasible. I hope that prices come down in 15 years time which is when I expect to replace my gas boiler.

 

I know this is environmentally the completely wrong approach, but the government just hasn't incentivised this technology properly and until they do I'm not keen on it.

[JohnMo]

6 minutes ago, Adsibob said:

costing something like £15k

 

7 minutes ago, Adsibob said:

government just hasn't incentivised this technology properly

Not sure the incentive helps, just causes more rip off companies to start up, rip of clients and then close the doors.

 

To buy a 6kW ASHP and the balance of materials can be around £2.5 to 3k, as a priced example a Grant Aerona³ 6kW is £2300 incl VAT (I paid £1300 for different make) plus 2 to 3 days plumbing and a day electrical to install.  So no idea how these companies can justify £15k.

[SteamyTea]

1 hour ago, JohnMo said:

no idea how these companies can justify £15k.

I think that is a zombie number that just won't die.

I heard in the radio the other day that fitting an ASHP can cost up to £14k.

Would be a bargain for some properties.

The only way to get a proper price is to know what you want, then get people to quote for it.

Then laugh at the sily ones.

[joth]

28 minutes ago, SteamyTea said:

I think that is a zombie number that just won't die.

I heard in the radio the other day that fitting an ASHP can cost up to £14k.

Would be a bargain for some properties.

The only way to get a proper price is to know what you want, then get people to quote for it.

Then laugh at the sily ones.

Completely. My 8.5kW ASHP cost £8.5k +VAT design, supply & installed, including MCS cert, supply ErP A 300L cylinder and connecting up UFH and a FCU for cooling. But this number is never the one quoted on here ... 🤷‍♂️

 

[joth]

1 hour ago, Adsibob said:

I won't be installing a heat pump, having investigated these options at length at the time of design and concluded that the market was crazy. It was much cheaper, and less hassle, to get a highly efficient gas boiler, than go through the process of:

1. getting planning permission to install a more expensive air source heat pump, work out where to put the external unit so that it wouldn't bother us or the neighbours
2. borrowing money to pay for an even more expensive one of these: https://www.ochsner.com/en/ochsner-products/air-source-heat-pump/ (quoted to me at the time as costing something like £15k).

There are space constraints in my property that just make it non-feasible. I hope that prices come down in 15 years time which is when I expect to replace my gas boiler.

 

I know this is environmentally the completely wrong approach, but the government just hasn't incentivised this technology properly and until they do I'm not keen on it.

To be clear: I'm not trying to argue you should rip out the functioning boiler and put in and ASHP. My point was that's what the previous few posts seemed to incorrectly assume you already had done.

If you're going to install anything, I'd recommend an air to air heat pump aka air-conditioning unit in the specific room(a) that need it 

[Adsibob]

1 hour ago, joth said:

To be clear: I'm not trying to argue you should rip out the functioning boiler and put in and ASHP. My point was that's what the previous few posts seemed to incorrectly assume you already had done.

If you're going to install anything, I'd recommend an air to air heat pump aka air-conditioning unit in the specific room(a) that need it 

Thanks for clarifying. Yes, I think I’m going to install that, but only if installing the external blind on the Velux first doesn’t make a big difference.

[Adsibob]

3 hours ago, JohnMo said:

To buy a 6kW ASHP and the balance of materials can be around £2.5 to 3k, as a priced example a Grant Aerona³ 6kW is £2300 incl VAT (I paid £1300 for different make) plus 2 to 3 days plumbing and a day electrical to install.  So no idea how these companies can justify £15k.

I can’t remember the size I needed, but the heat loss requirements of my house are about 18kw or 19kw. It’s a large 1930s house that has had insulation added as part of an extensive refurb and extension, but nowhere near passiv standards. And only 2G windows.

Edited March 8, 2023 by Adsibob