Air Source Heat Pumps

richardc1983

Craigix how did you get away with installing them yourself since you need refrigerant handling certificates to deal with them.

Same as corgi registered etc for gas boilers.

rothers8080

They were pre-charged.

richardc1983

Did you have to put any pipe work in at all then? or was it the self fit pipework where its flexible?..

If you had to vac out any copper pipe then were handling refrigerant its down to the risk that it might escape if not done properly... not saying you havent done it properly though!

richardc1983

craigix wrote: »

Quick update after my posts back in 2007.

Two excellent units, both inverters, both keeping my house at 23 degrees and it's -7 outside! Had them over a year now. Self installed, Great stuff.

What are the indoor units like? Any pics?

greendwarf

craigix wrote: »

They were pre-charged.

Sounds similar to my B&Q Airforce unit. The refrigerant is pre-loaded in fixed length pipework which uses self-sealing connectors at either end. Fitting was rather like wrestling with an anaconda:rotfl:

rothers8080

Even if you buy a unit second hand you can buy the pipework and still fit it yourself - just make sure the previous owner shuts the unit down correctly before removal (ideally you would be buying from an aircon engineer) and the gas is all still there, sealed in the outside unit.

Those clip on connections do make things quick but working with the cooper pipe is pretty cool once you are used to it - plus you can cut it to the exact length. A cheap vacpump can check you don't have any leaks before you release the gas.

Here is one of my indoor units, the cable you can see on it actually goes up to a plug socket at ceiling level. Everything else is behind the plasterboard. By sinking it in to the wall we essentially make ourselves a 'slimline' unit! Oh and that's an ecoair unit, which have the best display of any unit I've ever seen. Temp + energy use (a green bar) always visible - encourages you to drop by one degree and see how much energy is saved. Shame they are twice the price these days.

Andy_WSM

-7C here this morning and my Trianco is struggling to maintain temps. I do have a tank of hot water and radiators are warm, not hot. It's just about holding it's own though as all house set points are there or there abouts. Any colder than this I think would be a problem.

It's one of those days where you can feel the cold radiating off the windows & doors as you walk past them!

-edit - Spooky, but record low I have recorded here in 5 years was -6.7C on the 7th Jan 2009, a year to the day. The current temp is exactly -6.7C!

rothers8080

Andy_WSM wrote: »

-7C here this morning and my Trianco is struggling to maintain temps. I do have a tank of hot water and radiators are warm, not hot. It's just about holding it's own though as all house set points are there or there abouts. Any colder than this I think would be a problem.

It's one of those days where you can feel the cold radiating off the windows & doors as you walk past them!

-edit - Spooky, but record low I have recorded here in 5 years was -6.7C on the 7th Jan 2009, a year to the day. The current temp is exactly -6.7C!

Would it be possible to buy a second unit and put it in-line only to be used in conditions such as that? I've got a huge 9kw air-water unit which I've not installed yet.

Andy_WSM

craigix wrote: »

Would it be possible to buy a second unit and put it in-line only to be used in conditions such as that? I've got a huge 9kw air-water unit which I've not installed yet.

It would be possible, but it's not worth it really. This Winter is the exception to the norm. Last Winter's -6.7C was exceptional because we are coastal and don't normally get frost! This Winter has blown all records for the last 30 odd years out of the window!

This isn't likely to happen again while I live here!

Temp is now -7.0C which is a once in a 30 odd year event for this location.

Cardew

Andy_WSM wrote: »

It would be possible, but it's not worth it really. This Winter is the exception to the norm. Last Winter's -6.7C was exceptional because we are coastal and don't normally get frost! This Winter has blown all records for the last 30 odd years out of the window!

This isn't likely to happen again while I live here!

Temp is now -7.0C which is a once in a 30 odd year event for this location.

It seems to me that rather than spend loads of money to cope with these exceptional conditions, it would be more sensible to accept that you might have to run a 3kW fan heater to supplement the ASHP heating for a few days each year.

At the sort of temperatures we are getting I doubt if the COP of systems is much above 2.

So a 3kW heater running flat out for say 10 hours a day would cost £1.50 a day more than an uprated ASHP would cost to run - £10 a week.