Hitachi Yutaki (ASHP and Indoor Unit & DHW Cylinder)

nxdmsandkaskdjaqd

Are there any other members on here that have the Hitachi Yutaki (ASHP and Indoor Unit & DHW Cylinder)? 

I have just moved to a property with this system and looking for some help. 

Equipment:

• As far as I can tell it's S Combi, this is the model number RWD-3.0RW1E-220S-K, so the HW tank is within the indoor box.
• The heat pump is RAS-3WHVRP1, which I believe is a 3KW machine

System:

• All undefloor
• Heatmiser controls, with thermostats in all rooms
• No cooling 
• No heat coils
• No auxiliary heat source
• 50lt buffer tank
• Hot water set to 45C
• At present I have no info on the temperature compensation settings

The building is:

• A modern bungalow 
• Very low air tightness (2.3)
• Designed heat requirement 12 Kw

Rodders53

Best ask the questions you have and some kind soul might find and read the manuals if very specific;  but some may be fairly generic and apply to most similar installs.

It's wise to state if home-owner or a Tenant and if a brand new-built home or approx age of the install. As advice will probably be different if you rent or its under a guarantee of any sort.

nxdmsandkaskdjaqd

I believe, based on my research, the equipment is quite different to some of the ASHP currently available.

I am the home owner and the kit is about a year old.  With winter around the corner, I wanted to know more about the system, how people had found it, and similar config settings.

Netexporter

It looks very similar to systems by many manufacturers as, essentially, they're all the same. There will be differences in efficiency, under standard test conditions, but generally will be in the same ballpark. What makes the biggest difference is the design within the house; radiator and pipe sizing, the design temperature used to calculate the former, control systems, zoning etc.

Low ans slow is the overall mantra. It is not a gas boiler, so don't expect to walk into a cold house, whack it on and expect radiators you can't touch in 15 minutes. Heat pumps are ideally run pretty much continuously during the heating season, with a night-time temperature set-back of about 3 degrees. You don't need the domestic hot water at 60 degrees, apart from the periodic legionella cycle, which is generally programmed in; 45 to 50 degrees is generally hot enough if the hot water provides enough for your needs.

I assume you have a smart meter, as the house is new, so get on a suitable tariff. Octopus Cosy is probably a good place to start.

Rodders53

This is like drawing teeth.
It's not radically different from any other "high temperature capable" ASHP (some also may also have cooling capability Hitachi mention - but is it installed)?. 

It is, officially the Yutaki-S or the Yutaki S combi if the HW tank is not separate from the indoor box. See https://www.hitachiaircon.com/uk/ranges/heating/yutaki-s 

Do you know which design option / version you have installed?
Mono valent or Mono energy (where an auxiliary 1:1 heat source is needed on the coldest days)
Does it have the cooling option installed?
Which refrigerant (more recent R32 or the older R410A)?  Efficiency is different.

Radiators or wet UFH?
Any heat coils (blown air) installed?
What additional controls (if any).

What temperatures and times are set at the moment? Both CH and HW?

Have you downloaded the manuals from Hitachi and had a good read of them?  They may be well written... The Hitachi Technical Manual certainly seems to be and is written for the UK market, to boot (so that's good)!

matelodave

With all the info up front you wont get random guesses (or not too many). Many of us have got systems and they all differ in some respect so you need to be a bit more specific in defining what you've got and what you want to know

As suggested above, tell us exactly what unit you've got (the model type is likely be on a rating plate somewhere). What sort of heating system, radiators, undefloor etc. What controls have you got.

nxdmsandkaskdjaqd

Rodders53 said:

It is, officially the Yutaki-S or the Yutaki S combi if the HW tank is not separate from the indoor box. See https://www.hitachiaircon.com/uk/ranges/heating/yutaki-s 

Do you know which design option / version you have installed?
Mono valent or Mono energy (where an auxiliary 1:1 heat source is needed on the coldest days)
Does it have the cooling option installed?
Which refrigerant (more recent R32 or the older R410A)?  Efficiency is different.

Radiators or wet UFH?
Any heat coils (blown air) installed?
What additional controls (if any).

What temperatures and times are set at the moment? Both CH and HW?

Have you downloaded the manuals from Hitachi and had a good read of them?  They may be well written... The Hitachi Technical Manual certainly seems to be and is written for the UK market, to boot (so that's good)!

Equipment:

• As far as I can tell it's S Combi, this is the model number RWD-3.0RW1E-220S-K, so the HW tank is within the indoor box.
• The heat pump is RAS-3WHVRP1, which I believe is a 3KW machine

System:

• All undefloor
• Heatmiser controls, with thermostats in all rooms
• No cooling 
• No heat coils
• No auxiliary heat source
• 50lt buffer tank
• Hot water set to 45C
• At present I have no info on the temperature compensation settings

The building is:

• A modern bungalow 
• Very low air tightness (2.3)
• Designed heat requirement 12 Kw

I have downloaded the manual (130 pages), but a bit beyond me at present.

I am paying for a heating engineer to show me how to work the system.

Reed_Richards

nxdmsandkaskdjaqd said:

• The heat pump is RAS-3WHVRP1, which I believe is a 3KW machine

The building is:

• Designed heat requirement 12 Kw

12 kW is large for a modern bungalow, unless it is huge.  I hope this is wrong because if the designed heat requirement is 12 kW you would need a heat source with an output greater than 12 kW, so a 3 kW heat pump would be completely inadequate.

nxdmsandkaskdjaqd

Reed_Richards said:

nxdmsandkaskdjaqd said:

• The heat pump is RAS-3WHVRP1, which I believe is a 3KW machine

The building is:

• Designed heat requirement 12 Kw

12 kW is large for a modern bungalow, unless it is huge.  I hope this is wrong because if the designed heat requirement is 12 kW you would need a heat source with an output greater than 12 kW, so a 3 kW heat pump would be completely inadequate.

The property is 179 square metres with an EPC 92+

Reed_Richards

I don't believe that EPCs are hugely accurate but 92+ would be the top "A" rating. 

My bungalow is timber-framed built in 1980.  The EPC rating went from D to B (82) after I got solar panels.  The EPC says my floor area is 167 square metres.  My bungalow was calculated to need 8.9 kW to maintain a room temperature of 21 C when the outside temperature is -3.7 C.  To meet that requirement and also supply hot water I have a 12 kW heat pump.