Fancoil plan P (yes, there’s been lots of iterations….)

[G and J]

Methinks the hard part will be the control system, especially the user interface.

 

I hope to use the DAF model based on a single switch (instead of the gear knob).
 

Heat-Off-Cool.

 

I might make it look clever by having a bank of flashing lights and some 50’s Ipcress File computer type noises alongside said three position switch, maybe even an “Achtung! No Gerfingerpoken! Verboten!” sign in red letters too.

 

This will be above a non-latching, push to make switch behind a really big red button labelled “in case of nuclear fall out, steam or excessive farting, press once” which will be the user interface for the MVHR.

[JohnMo]

12 minutes ago, G and J said:

Heat-Off-Cool

Heat cool switching should be zero volt switching same as remote on off.

 

So you may need two switched but could be a double light switch, one switch on/off the other summer/winter.

[G and J]

4 hours ago, JohnMo said:

Heat cool switching should be zero volt switching same as remote on off.

Meaning I can’t just use a normal physical switch, or at least, I then have to use it through another zero volt switching device. 
 

I'm guessing this is to protect vulnerable components in the heat pump?

[JohnMo]

9 hours ago, G and J said:

Meaning I can’t just use a normal physical switch, or at least, I then have to use it through another zero volt switching device. 
 

I'm guessing this is to protect vulnerable components in the heat pump?

Yes normal switch, just a 2 core cable from switch to ASHP for mine. Many will do it via the controller.

 

Edited August 21 by JohnMo

[G and J]

3 hours ago, JohnMo said:

Yes normal switch, just a 2 core cable from switch to ASHP for mine.

OK, I’m officially confused.  
 

That doesn’t look like a clever zero volt switch.  If you’ve only got a two core cable back to the ASHP then presumably that’s just on/off, so how does the pump know whether to cool or heat?

 

I’ll take deep breaths and try and stay calm whilst hoping for a comforting circuit diagram to ease my perturbations.

[JohnMo]

6 hours ago, G and J said:

OK, I’m officially confused.  
 

That doesn’t look like a clever zero volt switch.  If you’ve only got a two core cable back to the ASHP then presumably that’s just on/off, so how does the pump know whether to cool or heat?

 

I’ll take deep breaths and try and stay calm whilst hoping for a comforting circuit diagram to ease my perturbations.

Remote control functions are either open or closed zero volt contacts. One set of contacts are for heat or cool, the other set for heat or cool off.

 

Remote On/off is via a volt free thermostat, this inhibits heating or cooling when it's an open contact see ID3 below

 

Summer winter 

Open contact or closed contact selects either heat or cool. See ID2 below.

Terminal block

 

 

 

Edited August 21 by JohnMo