Hi HMK,

Welcome to the forum and thank you very much for sharing your experience.

I agree with you fully about the poor quality and poor level of service that is now becoming the norm rather than the exception. Long gone are the days when the customer was always right.

In the past, I too have had to take the route to higher management after being fobbed off by lower management. Unfortunately the process these days would appear to be 'make it as difficult as possible to get service' in the hope that people will eventually give up. I feel that we should 'name and shame' more often.

Welcome to the forums HMK. I understand that you don't want to reveal the name of the installer. May I please enquire about the  make/brand of the heat pump?

Hi Mars, I am still in discussions with the manufacturer as I feel that the product was of faulty manufacture. I will keep the forum up to date with developments as I feel this would help others in a similar situation. I am sure I can reveal the name of the manufacturer shortly, hopefully as a result of a positive outcome.

@hmk, no worries. Look forward to an update.

Update on current situation regarding my failed heat pump.

The manufacturer has sent their own engineer to inspect my installation (at their expense) and determined that my system is properly designed and that the heat exchanger has failed and leaked gas into my system rather than externally, also the internal expansion vessel has failed, which they are claiming was the cause of the heat exchanger failure. My system has a larger expansion vessel and I find it surprising that the failure of a part such as the expansion vessel can have such an impact on the far more expensive heat exchanger which is normally quality tested to 30 bar.

They have agreed to provide a replacement heat exchanger and expansion vessel at their expense and I will pick up all other costs. Must not reveal any specific details of deal nor quote manufacturer. Hopefully all will be back in working order next week in time for cold weather approaching. Happy days!

@hmk 

Hi HMK,

There are various reasons why equipment and/or systems fail.

One reason could be flaws in the original materials used to construct the component part.

Another could be faulty manufacture or damage during transit.

Damage could have occurred during installation.

Operation outside the specified maximum operating parameters is also a possible reason for failure.

Wear and tear may also eventually lead to failure.

Without knowing the exact details of your system and component parts it is difficult to give definitive answers. I assume that since the refrigerant gas leaked into the water side, the leak is internal to the Condenser within the ASHP. The fact that the gas leaked in, rather than out into the surrounding air, would also indicate that the leak is internal to the heat exchanger. This would tend to rule out external damage.

An internal leak in the heat exchanger would possibly be caused by one of two things:-

Overpressurisation - though the ASHP controls should contain safety devices to shutdown the heat pump if the gas pressure gets too high. It should also generate alarms or warnings to indicate why the heat pump has shutdown. Did you receive any alarms or warnings?

Manufacturing weaknesses or excessive wear and tear - During operation of the ASHP, the compressor will pressurise the gas in the condenser, and then the gas pressure will fall, before the compressor builds up the pressure again. This is normal operation, but of course as the pressure increases and decreases, there may be slight movement of the metal within the condenser. Also as the pressure changes, so will the temperature, which will cause slight expansion and contraction of the metal parts. Movement of the metal parts, may over time, either cause or find weaknesses in the internal joints.

Was the failed expansion vessel internal to the ASHP or external?

Both internal, and external, expansion vessels are located on the water side, so the failure of either may have been due to the heat exchanger failing, rather than the other way around. There should be a pressure relief valve on the water side of the system, so it may be prudent to have this checked and prove that it is operating and correctly adjusted.

You are correct in your assumption that a correctly designed, manufactured and operated heat exchanger should exceed the manufacturers specified warranty period. Obviously, without more details and possibly inspection of the failed components, it is difficult to be any more specific.

One further aspect to check would be the concentration of antifreeze within the water system, and whether the ASHP was switched off during freezing weather conditions?

Thanks Derek M for your comments, I may have need of these as time progresses.

The latest in my saga is that the replacement parts arrived and I contacted my heat pump engineers to fit the parts, however as soon as they heard that the loss of f-gas was into the water system they backed off. They advised that the labour cost of ensuring that if any water had leaked back into the refrigeration system that this must be totally removed, and then fitting parts, regassing, and commissioning would be a sizable cost towards a new more reliable heat pump, and then in their experience this type of failure was very commonly followed by a cascade of further failures, such as the compressor, pump, etc.

Basically I am left with a pile of heat pump junk with a £10K+ replacement cost.

Thankfully my wife did not sign the gagging order so the whole matter in now in the hands of our insurance company's legal team, as we took out legal cover as part of our property insurance with the NFU.

I think Boris needs to get a hold on the heat pump manufacturers to ensure that all heat pumps are easily and economically repairable or there will be a massive backlash as housing developers install cheap and nasty heat pumps produced by companies cashing in on the boom, that fail just outside their warranty. People will not be happy with £8K to £12K heat pump replacements costs, less than 10 years after they purchase a property.

@hmk 

I think it a very wise move to involve your insurance company, is your ASHP covered by your policy? I think that some time ago there was discussion on the forum about insurance policies which excluded heat pumps.

Without knowing the actual brand and size, I would estimate the cost of a brand new replacement unit in the £3k to £4k range, though if it were supplied at cost by the manufacturer it would be much less. You may be able to make the case that replacing the faulty ASHP with a brand new one, would be more beneficial to the company than all the 'free reviews' that you are prepared to provide.

Personally, I think you should try to push the manufacturer to replace the whole unit free of charge, and then allow them to take the old unit away for inspection, so that they can discover the true cause of failure.

As far as removing any water from the system is concerned, after the installation of any new parts, it would be necessary to remove all the air from the system by means of a vacuum pump. As any reasonably bright school boy should be able to tell you, water boils at lower temperature under vacuum, so by the simple fact of removing the air from the system, they should also remove any water that is present.

There is of course, also the possibility that the cause of the failure of the heat exchanger may have caused further damage or weakness within the ASHP unit, a new replacement unit would therefore be the preferred option. 

Hi HMK,

I would be very interested to hear how you get on with your repair. Some of your story has a familiar feel as we are without heating and awaiting a repair under warranty.

I think it would be good to have an ongoing discussion thread on peoples experience of the level of customer service they get from manufacturers, complex systems will always have failures, how these are dealt with is the key factor for customer satisfaction.

Hence in making a buying decision, efficiency, cost, etc are important, but none of these are much use if you are left freezing in the cold for weeks or months!

Update on Heat Pump repair

We contacted our insurers (NFU) who arranged some legal advice. The legal advisor suggested that we give the heat pump manufacturer a further opportunity to repair the heat pump so we contacted the manufacturer indicating that this was the legal advice given. They reluctantly sent an engineer to fit the parts they had previously supplied (with a gagging order) who fitted the parts and have left the heat pump working, however they were due to return to fit a new sensor (they did a bodge to get it working) but that has not happened. I am trying to find a heat pump engineer in the Forest of Dean area who can maintain and service our heat pump, but such a mythical rare creature appears not to exist!