Trianco 5KW heat pump noisy on start up.

[Andy_WSM]

My heating & hot water is provided by a 5KW Trianco air to water heat pump which is a few years (maybe 4) old now and works brilliantly.

The problem I have with it at the moment doesn't prevent it working, but makes it noisy when it starts up and the fan is on low speed. As soon as the fan speeds up the noise stops - so I'd have to guess it's a fan problem, although I have checked there is no play on the fan motor bearings.

Does anyone have any experience of these and has anyone encountered a similar problem?

For info the heat pump provides heat to a Smith Ecovector in each room, all on individual thermostats - excepting the bathroom which has a permanently on towel rail.

The heat pump runs 24/7 during the cold 4 or 5 months of the year and running costs are no more than about £3 a day, less any solar production during daylight hours, so some days just pence to keep the house warm.

[dhaslam]

I have one that is no longer working.   I think that the  fan did ocassionally make noise  but probably only  when it made the wire grill or one of the panels vibrate.   The fan is big for the  size of the heat pump so it is  reasonably quiet at  full speed and that should make it last  better.       I have put mine up into storage  so it would be available for parts.  Unfortunately spare parts seem to be very expensive so I didn't bother to repair mine.

[Philip R]

Andy,

Is the heat pump a three phase model or fed from single phase 240V?

Whatever, first things jumps to mind is a winding fault on the fan, for three phase I would have said it was single phasing, i.e. one of the three phases missing, makes motor hum. can run backwards if missing completely, but no torque.

Or it could be compressor just compressing the refridgerant upto the presure reducing valve. With a bit of back pressure, the piston will not flop around so much in the cylinder, if a scroll compressor, forget that theory. Could be a feature of the single phase split start circuit operation.

PhilipR

[Andy_WSM]

I have one that is no longer working.   I think that the  fan did ocassionally make noise  but probably only  when it made the wire grill or one of the panels vibrate.   The fan is big for the  size of the heat pump so it is  reasonably quiet at  full speed and that should make it last  better.       I have put mine up into storage  so it would be available for parts.  Unfortunately spare parts seem to be very expensive so I didn't bother to repair mine.

What went wrong with yours, do you know?

[Andy_WSM]

Andy,

Is the heat pump a three phase model or fed from single phase 240V?

Whatever, first things jumps to mind is a winding fault on the fan, for three phase I would have said it was single phasing, i.e. one of the three phases missing, makes motor hum. can run backwards if missing completely, but no torque.

Or it could be compressor just compressing the refridgerant upto the presure reducing valve. With a bit of back pressure, the piston will not flop around so much in the cylinder, if a scroll compressor, forget that theory. Could be a feature of the single phase split start circuit operation.

PhilipR

Single phase.

I did wonder whether I'd get away with disconnecting the lower fan speed windings so that the fan is either running on full or not at all. It doesn't stay on low for long at all anyway.

It's not too much of a problem and in all honesty, I've already had better service life out of this heat pump than I've had out of my last gas combi boiler - and MUCH cheaper too!

[dhaslam]

What went wrong with yours, do you know?

The error code was 08 described as Refrigerant pressure cutout #1 and it gives four alternatives, No Water, Airlock, Impared Water Flow and Cylinder sensor Detecting Incorrect Temperature.

I assumed  that the  pump wasn't working properly and tested it with an external pump but it just gave the same error after a few minutes running.    I'm not sure  what was actually causing the problem, it wasn't any of the problems listed,  and it didn't seem to be  anything that I could fix.     

[Andy_WSM]

What went wrong with yours, do you know?

The error code was 08 described as Refrigerant pressure cutout #1 and it gives four alternatives, No Water, Airlock, Impared Water Flow and Cylinder sensor Detecting Incorrect Temperature.

I assumed  that the  pump wasn't working properly and tested it with an external pump but it just gave the same error after a few minutes running.    I'm not sure  what was actually causing the problem, it wasn't any of the problems listed,  and it didn't seem to be  anything that I could fix.     

When your Trianco was working, did you get good performance from it?

Very very happy with mine. A replacement would "only" be about £850, so cheaper than having to replace a gas boiler for example anyway.

[dhaslam]

It did work quite well.  Even though the COP was only about 2:1  on average  it is very  inexpensive heating.  Unfortunately the two winters that  it was running were the coldest for years and last winter I had to turn it off during the coldest period.   I was reluctant to buy another one at present because  that was my second air source heat pump to fail and there isn't much opportunity to have them repaired here.        Using the  wood stove this winter is costing  about  €700 in wood. Electricity will be about €400 less, that was the combined cost of  the heat pump plus topping up DHW a little.    I was however using almost as much wood in the old stove  without it heating  heating very much.     

I would still consider a heat pump  in the future just because handling wood may become a problem.    In the meantime the solar heating system is getting a major overhaul.   Presently about 75% of the generated heat is lost  with poor insulation and only  outputting water at about 30C on sunny days.  If I can get the output temperature up to over  40C  it will save using the stove quite a lot.

[Andy_WSM]

I had a bit of a break through yesterday afternoon.

I decided to get a ladder out and strip the fan motor out of the heat pump, clean it, grease the bearings and reassemble - and now it can't be heard running from more than a few feet away. Very pleased as it sounds like I'll get a bit more service out of it yet

[Andy_WSM]

Still working perfectly. Just 3C out this morning and it's maintaining temps lovely - and more importantly - near silently!