Forums

Forums
Members
Heatgeek
Activity
 
Notifications
Clear all
Heatgeek
@heatgeek
Member
Reputable Member
Joined: Dec 16, 2024
Last seen: May 29, 2025
Profile Activity
Topics: 1 / Replies: 116
AllTopicsReplies
Reply
RE: Avoid the Heat Pump Villain: Why Low-Loss Headers and Buffers Can Sabotage Your Heat Pump's Efficiency

@potatoman As no one seems to be obliging, I attach a diagram. The idea is that only bypass flow goes through the tank when necessary so it is undistu...

1 month ago
Forum
Air Source Heat Pumps (ASHPs)
Reply
RE: Hitachi Yutaki SCombi Heat Pump - Thermal Off's

@trebor12345 The Auto function is supposed to adapt automatically and select the right curve in constant pressure mode. By default the pump is set to...

2 months ago
Forum
Air Source Heat Pumps (ASHPs)
Reply
RE: Hitachi Yutaki SCombi Heat Pump - Thermal Off's

@trebor12345 Your house is remarkably similar to mine, layout included. I have 185 sqms with 4 beds and 2 baths, same size lounge with exactly the sa...

2 months ago
Forum
Air Source Heat Pumps (ASHPs)
Reply
RE: Hitachi Yutaki SCombi Heat Pump - Thermal Off's

@trebor12345 Use the internal private messaging system on this forum.

2 months ago
Forum
Air Source Heat Pumps (ASHPs)
Reply
RE: Hitachi Yutaki SCombi Heat Pump - Thermal Off's

@trebor12345 Re your question about changing setting to controlled DT, this may be worth trying if your current DT is 1C as the heat pump will automa...

2 months ago
Forum
Air Source Heat Pumps (ASHPs)
Reply
RE: Hitachi Yutaki SCombi Heat Pump - Thermal Off's

@trebor12345 There doesn't seem to be anything obvious on the refrigeration cycle as the temperature ups and downs look logical. However your DT is e...

2 months ago
Forum
Air Source Heat Pumps (ASHPs)
Reply
RE: Hitachi Yutaki SCombi Heat Pump - Thermal Off's

@trebor12345 I can send you a service manual however it is very large (200MB) so exceeds the file size limit here. If you can send me an appropriate ...

2 months ago
Forum
Air Source Heat Pumps (ASHPs)
Reply
RE: Hitachi Yutaki SCombi Heat Pump - Thermal Off's

@trebor12345 The penny has finally dropped. I thought you were describing defrost sequences. If you say that this happens at 20C OAT, it is not norma...

2 months ago
Forum
Air Source Heat Pumps (ASHPs)
Reply
RE: Hitachi Yutaki SCombi Heat Pump - Thermal Off's

@trebor12345 @jamespa From the calcs you sent, your house conforms with modern insulation standards e.g. roof u-value 0.11. Your overall heat loss is...

2 months ago
Forum
Air Source Heat Pumps (ASHPs)
Reply
RE: Hitachi Yutaki SCombi Heat Pump - Thermal Off's

@trebor12345 The heat exchanger function is the same regardless of whether it is inside or outside. Your heat pump is a 7kW unit, not 3kW as per y...

2 months ago
Forum
Air Source Heat Pumps (ASHPs)
Reply
RE: Hitachi Yutaki SCombi Heat Pump - Thermal Off's

@trebor12345 By way of further explanation, in cooling mode the compression cycle of the heat pump reverses i.e. the gas flow goes in the opposite d...

2 months ago
Forum
Air Source Heat Pumps (ASHPs)
Reply
RE: Hitachi Yutaki SCombi Heat Pump - Thermal Off's

@trebor12345 Firstly, the brochure description of the Hitachi says that it definitely uses hot gas bypass for defrost as per the process I described...

2 months ago
Forum
Air Source Heat Pumps (ASHPs)
Page 2 / 10
Share:

Join Us!

Trusted Installers

Struggling to find a reliable heat pump installer? A poor installation can lead to inefficiencies and high running costs. We now connect homeowners with top-rated installers who deliver quality work and excellent service.

✅ Verified, trusted & experienced installers
✅ Nationwide coverage expanding
✅ Special offers available

👉 Find your installer now!

Latest Posts