Are there any other reversible monobloc ASHPs in the 4-5kW max output range...

Daikin EBLA04 (R32 based)

Vaillant aroTHERM Plus v2 3.5kW

Samsung 5kW Gen 7 R290 

Grant Aerona 290 4kW HPR2904

 

TIA

Haier R290 4kW, comes out the box setup for heating and cooling, wouldn't bother with R32 as R290 in the real world performs better as they are generally the next generation design.

Midea M Thermal. Pretty trivial to switch between heat/cool/both using the built in controller

Of the modern r290 ones are there any that don't support cooling?

43 minutes ago, -rick- said:

Of the modern r290 ones are there any that don't support cooling?

Octopus, Ebac, a lot of Mitsubishi and Daikin ones, don't support cooling at all and others. Valiant needs a widget to make it work, Grant only enables cooling if you do not select radiators within your heating system.

 

Not sure about Viessmann.

 

Panasonic does support cooling also out the box.

10 minutes ago, JohnMo said:

Octopus, Ebac, a lot of Mitsubishi and Daikin ones, don't support cooling at all and others. Valiant needs a widget to make it work, Grant only enables cooling if you do not select radiators within your heating system.

 

Wow, ok. That's a lot more than I thought.

FWIW one of Valliant guys on their stand at the NEC a couple of weeks told me they included the resistor for cooling with the plus model.

Well I raised potential cooling with the service engineer who came today. Mines a Vaillant and whilst it apparently can do it he didn't recommend it as the "underfloor pipes can contract and crack the concrete". I wasn't going for the sub-zero approach, merely say 16 degrees.......

2 minutes ago, kandgmitchell said:

Well I raised potential cooling with the service engineer who came today. Mines a Vaillant and whilst it apparently can do it he didn't recommend it as the "underfloor pipes can contract and crack the concrete". I wasn't going for the sub-zero approach, merely say 16 degrees.......

That will be right - not 

Quite!

We have a 6kW R290 Maxa.  Slightly higher power than you ask for but seems to be ok.  Comes in a pleasant colour too (for it’s position in our garden).

 

Is there any difference in sound level in general between R32 and R290?

10 hours ago, G and J said:

sound level in general between R32 and R290?

Comparing our Maxa R32 (now heating our hot tub) and Haier R290, the R290 makes slightly less noise, but both are not noisy. The R290 has a bigger fan that runs slower and a bigger evaporator, so air flow rate is lower circa given load.

Edited Friday at 07:445 days by JohnMo

I would include the Vaillant 5kW, which is the model i have.

Don't discount it just because you need the resistor, its less than £10 even if you have to buy one and its trivial to fit.

On 16/10/2026 at 08:43, JohnMo said:

(now heating our hot tub)

Thread hijack alert- how did you plumb this? PHX? I want to use the HW cycle from my second HP to do this for our HT, have bought all the parts but just haven’t gotten around to doing it. Just wondered if I was overcomplicating…

5 kw panasonic J series. WH-MDC05J3E5

Does cooling out of the box. Very easy to set up, cheap as chips, and now available in anthracite.

The Cool Energy units can do cooling out of the box, not sure if they go small enough.

2 hours ago, Wil said:

Thread hijack alert- how did you plumb this? PHX? I want to use the HW cycle from my second HP to do this for our HT, have bought all the parts but just haven’t gotten around to doing it. Just wondered if I was overcomplicating…

Pretty simple plumbing, I just have an after filter and used thick wall hose as pipe, which is also insulated. One issue that came up was main pump cavitation due to the pump being at top of the ASHP package. So have installed a spare Wilo pump I had laying around. This is in the suction line and runs 24/7.

Main ASHP only runs in Cosy tariff windows and use a timer acting on the external thermostat terminals.

But I cannot use chlorine based chemicals, so use a bunch of copper fittings in a bag, non chorine shock dose intermittently and sodium peroxide (12.99%) as routine bio-growth prevention.

But you would need to keep CH water and HT water apart. Chlorine stuff above would also apply unless you use a titanium heat exchanger as opposed to Stainless 304 which are more normal

@JohnMo Thanks, I got a Bowman heat exchanger, but the thought and pain of cutting into the pipework under the tub is what puts me off most. I tend to use Bromine rather than chlorine but haven’t looked into changing chemicals.

I’m also trying to plumb this in parallel with the existing element and controls to keep those running once warm. HT hasn’t had water in it for a couple of months while I scratch my…. Head

Bromine is just as bad I believe for 304 stainless if that's the material of you heat exchanger. Mine is easy to plumb, as it's a wooden HT with side connections