Compressor central heating - breaking every week or so

[snb]

In cold weather the evaporator of an air sourced heat pump may ice up and shut down. The cure is supplimentary heating to de-ice the evaporator ( the outside unit ). Has supplimentary heating been installed and if so (1) is it enabled and (2) is it adequate for the cold weather in recent weeks.

Too much reading on google will cause you to sprout in correct info. You need to understand current install practices and the units that we fit currently. We have changed the gas used in units and changed to invertor driven which don't require supplementary heating. The unit goes into reverse cycle to defrost itself.

All of the symptoms described point down to a system that has either not been installed correctly, not been setup correctly or both. However you also have the problem of homeowners interfering with setups either on purpose or by mistake.

You need to be there when the engineer comes to get it going and find out what he has had to do. But in the mean time you maybe able to just turn the power off for one minute and then turn the system back on

 

[NotebookNewport]

Cheers

 

[bernardgreen]

changed to invertor driven which don't require supplementary heating.

Invertor drive reduces the start up loading when the compressor starts.

The unit goes into reverse cycle to defrost itself.

That is true for systems that are intended to provide house heating in winter and house cooling in summer. Air sourced heat pumps designed only as house heating units do not have the extra complexity of a reversing valve and thus cannot depfrost there evaporator coil other than by supplimentary heating.

 

[snb]

Invertor drive reduces the start up loading when the compressor starts.



That is true for systems that are intended to provide house heating in winter and house cooling in summer. Air sourced heat pumps designed only as house heating units do not have the extra complexity of a reversing valve and thus cannot depfrost there evaporator coil other than by supplimentary heating.

I fit, commission in others installs and repair them. So there is almost certainty that I know how they work. Please don't try to justify your lack of knowledge with utter crap.

So you start Googling in the right direction. Invertor driven means in simple terms that rather than fixed output we have variable output to reduce cycling. Just about all heat pumps installed in the UK have the ability to heat and cool. We use these because our humid climate causes the units to frost up and reverse cycle is the most efficient and quickest way to defrost

 

[Dan Robinson]

FFS, Bernie found another subject to comment on with no practical knowledge.

 

[bernardgreen]

Please don't try to justify your lack of knowledge with utter crap.

Bernie found another subject to comment on with no practical knowledge.

Once again Mr Robinson demonstrates his ignorance of my history.

Between 1979 and 1981 the heating system planned for the house was to be heat pumps using a stream as the heat source, Designed with input from the Philips Experimental Hoise team and other experienced people who were operating heat pump systems the prototype was going to be used to heat the on site caravan that we would be living in during the build. Then the gas board relented and agreed to extend gas mains to the area and heat pumps were discarded on favour of gas. The design work was passed to others and has been used.

I do recall the advice to avoid using a reversing valve ( ie no cooling in summer ) as they were ( at the time ) considered to be problematic. When using a stream as the heat source evaporator de-ice was not a requirement.


This is from 2009

http://www.davidstrong.co.uk/web_documents/air_source_heatpumps1.pdf

It does mention running the heat pump in reverse to de-ice the evaporator but make the point that this is at the expense of removing heat from the building and nence mentions the alternatives,.

 

[Dan Robinson]

Between 1979 and 1981 the heating system planned for the house was to be heat pumps using a stream as the heat source, Designed with input from the Philips Experimental Hoise team and other experienced people who were operating heat pump systems the prototype was going to be used to heat the on site caravan that we would be living in during the build. Then the gas board relented and agreed to extend gas mains to the area and heat pumps were discarded on favour of gas. The design work was passed to others and has been used.

So not only was this 37 years ago, it wasn't even carried out. So... you have no PRACTICAL experience whatsoever, and what theoretical experience you have is 31 years out of date or gleaned from an equally out of date document written before the wide adoption of inverter technology.

As for the suitability of the OP's house for a heat pump, I find it very unlikely that it was a wise move installing one:

They had new radiators too

That shows some consideration, however unless the house is veeery new, I doubt the natural levels of insulation would make it viable. Especially as @snb mentioned, if there was natural gas already there.


Reminds me - need to go to site tomorrow and put the Glycol into the Samsung unit we fitted the other week.

 

[dilalio]

Reminds me - need to go to site tomorrow and put the Glycol into the Samsung unit we fitted the other week.

Don’t forget the leaky rad in the office