@editor  (South East Costs vary - £175 to £300) for a full system service the reason the costs is twice a boiler is because it should take twice as long and there is a massive shortage of engineers that know what they are doing 🙂

Items that should be checked on the Monoblock

F-Gas leak check:- non intrusive (it is against the rules for any F-Gas engineer to attached their gauges unless there is a suspected gas loss) you can tell a gas leak by the following tests. Measure Sub-cooling, super heat, heat exchange and generated temperature measures, these measurements are subject to Hz of compressor drive and at which stage the system is operating (a good engineer know the stages). We also have tools that clip to all the locations for measuring performance without touching the gas circuit, input the gas type and measure which will tell you if its suspect.  

Mitsubishi approved contractors also carry electronic adaptors that plug into the monoblock and allow us to see a bit more info.

Cleaning of all coils, strainers, filters, outlets and inlets (inc clearway of tundish line for safety valve. (please note all pressure relief valves should be change every 5 years) 

Water pressure checks, operation, seals, connections and readings

Physical inspection of structure, frame rust, mounts, bolts and screws and powder coat paint

Inspection the same as above to the DHW tank 

Electrical and connection check of controls, pressure relief test

History check, clear faults and inspect past errors. 

Check glycol lvl with refractor (then convince the client to fit anti-freeze valves and get rid of the toxic stuff :)) if they wont, then get rid of the toxic stuff and fit the valves for free:)

Full programme test mode:- primary pump pulse test and run test speed 1,2,3,4 and 5, repeat to secondary and DHW pump 

Valve test, flow sensor test, self test, error check.

Various codes to check all thermistor readings and LEV pulse stage, LEV reset, inverter fan test, compressor check.

And the bit you all see done and some companies think is a full service :):- clear away foliage, clean the Monoblock and deep clean the evaporator coil 🙂

All of the above should take around 2hrs assuming all goes well.

These systems are much more sophisticated than a household fridge, a fridge almost always has a heatloss through its insulation or a plate on the back so no fan and sits in the same temperature most of it life, the fridge also only heats a plate inside the fridge. this system never varies never changes state just cycles on and off as needed. The ASHP relies on exchanging its heat in a circulation with the house that varies, is outside where the temp varies and is capable of a varied output as required.

Think of it this way, you had a pushbike that you didn't service for 20 years and that was ok but you could not say the same for a motorbike, the ASHP is a bit closer to a motorbike than a push bike but the both move on wheels.

@ashp-bobba cost me around 400 quid to get a bloke out to do a full diagnostics on mine so I could rebuild it properly, he doesn’t do servicing or repairs, doesn’t need to.  You try and get someone qualified in heat pumps and I hear online that even the heat geek scheme is flawed. The heat pumps are way ahead of the industry and a refrigeration engineer would probably be a better choice and more likely to have the tools than a heating engineer. When I worked for salvesen logistics I worked on refrigeration as one of my roles and if you gassed a fridge on the wrong cycle you would hydraulic it and destroy it, likewise if you didn’t vac it properly the air caused corrosion.  I doubt any heating engineer could vac and gas let alone diagnose a fault. 

we are all in trouble because not only can they not install them properly but having just had a service it’s clear they can tic boxes but clueless.  

@david999 Ah, I kind of agree with a lot of what you are saying, I cant comment on the heat geek scheme as I dont know it well but from what I could see is they are trying to champion and bring awareness to the tech.

I see it like this, you need 5 engineers for every ASHP life cycle or 1 engineer who is an expert in all.

Electrician, controls engineer, design engineer, F-gas engineer, heating skilled plumbing engineer.

Stage 1, you only need a design engineer

Stage 2, you mainly need a heating engineer as they would understand the systems best be it high temp systems is what they are used to.

Stage 3, you need an electrician for the power supplies and either the heating eng or the elec will need to attempt the controls (controls engineer often needed)

Stage 4, you now need one of the above to try and work out why your low temp system does not quite work how expected or praise when it does.

2-10 years later

Stage 5, care of the system will need an AC, Heating, Plumbing, Controls, Elec and probably help for the designer to keep this box of tricks working nice. Reason for all is as below, 6 months - 10 years life cycle assume a fault occurs, I will list what I think is probably the most appropriate engineer to attend and remember at this point we dont know whats wrong with the system.

System air locks - Heating plumber

System pump or flow issue - Heating plumber

Power failure (but system ok) - Electrician 

Mechanical issues - Heating plumber / AC

Controls issue - Heating plumber, AC, electrician will try but you will need a controls or design engineer that understands the workings if the fault is complex, or some good after sales support from the manufacturer. 

There seems to be a few companies springing up to install these but not much service support, also worth noting I though Octopus has opened a whole service company and you can get a plan? might be best to go that way with the whole thing and let a major supplier take care of these systems for a monthly £35 or something.