Joining the Renewable Heating Hub forums is completely free and only takes a minute. By registering you’ll be able to ask questions, join discussions, follow topics you’re interested in, bookmark useful threads and receive notifications when someone replies. Non-registered members also do not have access to our AI features. When choosing your username, please note that it cannot be changed later, so we recommend avoiding brand or product names. Before registering, please take a moment to read the Forum Rules & Terms of Use so we can keep the community helpful, respectful and informative for everyone. Thanks for joining!
@johnmo no set backs in winter, just 24/7. I did get it to the point that it was working better but before that there were some days when it was very damp air and at 3/4 degrees just defrosting every 40 minutes or so all day so it struggled and then the outside temp would go to -5 at night.
it ended up OK but it’s clear that we have missed out by not having a LLH or volumiser fitted.
Posted by: @marvinator80@johnmo no set backs in winter, just 24/7. I did get it to the point that it was working better but before that there were some days when it was very damp air and at 3/4 degrees just defrosting every 40 minutes or so all day so it struggled and then the outside temp would go to -5 at night.
it ended up OK but it’s clear that we have missed out by not having a LLH or volumiser fitted.
The grant volumiser are quite good. Hook up as per their instructions think they say in the return pipes.
@dodgyknee hi, here's Group 46 parameters changed from default for me, default in [ ]
46 00 = 3 [0] heater enabled in supplementary mode
46 01 = 45.0 [50.0] set this to your maximum design LWT in heating
46 02 = 1 [5] 1 min delay on heater activation in defrost
46 05 = 0 [600] no integration time, there's already a 1min delay above
46 11 = -20 [5.0] don't want compressor to disable when heater enables!
46 13 = -5.0 [5.0] I only want immersion to boost heating when it gets really cold, below -5degC
46 14 = 2.0 [5.0] and switch off when outdoor temp rises to -3degC
46 20 = 3 [0] this enables the immersion heater to boost defrost function & be a second heat source in really cold weather.
46 23 = 38.0 [24.0] set higher than default, as I want the heater to come on 1m after defrost start, by which time the LWT is falling and soon reaches 38degC. If it doesn't energise until 24degC it's not really of any benefit.
Oh God.
I don’t know if I have done something to my Grant controller.
I held in the buttons to check LWT and parameters earlier and now when I do it it doesn’t seem to work. Just goes to resetting the date and time.
perhaps I am cracking up.
Oh God.
I don’t know if I have done something to my Grant controller.
I held in the buttons to check LWT and parameters earlier and now when I do it it doesn’t seem to work. Just goes to resetting the date and time.
perhaps I am cracking up.
and when I press the Return only button it just beeps and does nothing else. 😞
Posted by: @marvinator80Oh God.
I don’t know if I have done something to my Grant controller.
I held in the buttons to check LWT and parameters earlier and now when I do it it doesn’t seem to work. Just goes to resetting the date and time.
perhaps I am cracking up.
and when I press the Return only button it just beeps and does nothing else. 😞
Go on google (or other) and find and download a Chofu R32 installation manual. Everything you need to know will be in there.
Posted by: @marvinator80@derek-m it worked. Thank you 🙏
You should always try the 'Universal' reset first if possible.
Unfortunately poorly written software can sometimes get its 'knickers in a twist' when buttons are pressed in the wrong sequence, rather than issuing the message 'what on Earth are you doing Dumbo'?
- 26 Forums
- 2,618 Topics
- 61.1 K Posts
- 967 Online
- 6,993 Members
Join Us!
Worth Watching
Latest Posts
-
RE: Indevolt Batteries UK Support & Info Thread
Thanks @editor , @indevolt-uk Subject to any comments ...
By JamesPa , 6 hours ago
-
RE: Share Your Experiences with Heat Pump Manufacturer Support
@seoras Sorry to hear that. I found Vaillant very help...
By JamesPa , 7 hours ago
-
The Watchdog That Watched and Waited
On 9 January 2026, Consumer Energy Solutions collapsed ...
By Mars , 10 hours ago
-
RE: GSHP Kaput After 16 Years: New Compressor or Switch to ASHP? Advice Welcome
Cool Energy in Grimsby sell ground source heat pumps an...
By DerekDeLeon , 11 hours ago
-
RE: Valliant Heat Pump Settings
Thats arguably a sign of a good installer - they unders...
By JamesPa , 12 hours ago
-
RE: Electricity price predictions
Well, we have so many cases where rain water mixes with...
By Batpred , 13 hours ago
-
RE: Two heating zones to one zone
@profzarkov They arent obviously wrong, but the only...
By JamesPa , 15 hours ago
-
RE: Towns water feed to air source heat pump system
The DHW circuit cant be separated (well it could, you c...
By JamesPa , 15 hours ago
-
Solis AC-coupled 3kW storage inverter
Solis AC-coupled 3kW storage inverterPylontech batterie...
By MartinRobinson , 21 hours ago
-
RE: My NIBE ASHP Nightmare: No Commissioning, High Bills and a Hostile Installer
As @transparent has observed above, this is not bad, an...
By cathodeRay , 22 hours ago
-
RE: The Grid Says Yes.. Until It Doesn’t: Why Britain's Net Zero Push is Stalling at the Plug Socket
As I was reading this article Mars, I was thinking that...
By Toodles , 2 days ago
-
RE: Tell us about your Solar (PV) setup
Installed in May 2011: 16*Sharp 245 W monocrystalline p...
By txmartyn , 2 days ago
-
-
RE: Say hello and introduce yourself
That doesn't sound 'right' to me. The national Smart ...
By Transparent , 3 days ago
-
RE: Growatt battery disconnected
I doubt this will happen, but I will try and suggest it...
By Eliuccio , 3 days ago
-
Understood. That's why I decided from the outset on a ...
By JamesPa , 3 days ago
-
RE: My experience with 3 heat pump surveys: Heat Geek, British Gas & Octopus
On the litigation, I would not go there and definitely ...
By Batpred , 3 days ago
-
RE: Recommended home battery inverters + regulatory matters - help requested
I suppose if your pv inverter packs up, you have a plan...
By Batpred , 4 days ago
-
RE: New Vaillant aroTherm Plus in black - When will it come to the UK?
Firstly check you are using sound power not sound press...
By JamesPa , 4 days ago
-
That’s the solar up and running, I don’t think it’s the...
By David999 , 4 days ago
-
RE: Seeking ideas / information / commiseration - Pure Drive
I agree with @colinc that you can reuse some of it. A s...
By Batpred , 4 days ago
-
RE: Solar Power Output – Let’s Compare Generation Figures
@toodles Im trying me best to ignore orangeman, I figur...
By Papahuhu , 4 days ago
-
@toodles That’s way better per kWp performance than our...
By Papahuhu , 5 days ago


