Problems with Air Source Heat Pump

[brizy]

Hi ,
Ive a recent problem with Air Source Heat Pump in Heat Mode.
With Outside Air Temp at 1deg C the Outdoor unit pipework at the Outdoor Unit measures 58degC & 18 Deg C. and at the Input of the Indoor Unit the Pipework its 55 & 20 Deg C.
However I must of knocked the pipework a few weeks back & had a very slight leak on one of the fittings... I've nipped this up & checked everything tight with soapy water.. However temperatures inside are struggling to get above 20 degC & noticed that the outside evaporator only ices up at the bottom 1/3 & no higher( however i don't know if this is normal)... Would this be due to loss of coolant because pipe temperatures do seem pretty good I would think.. At 6dec C outside air temp yesterday the pipes at the Outdoor unit in Heat mode where 64deg C & 21Deg C respectively measured with a digital thermocouple.. Any help would be appreciated

[Bigfreeze]

Hi ,
Ive a recent problem with Air Source Heat Pump in Heat Mode.
With Outside Air Temp at 1deg C the Outdoor unit pipework at the Outdoor Unit measures 58degC & 18 Deg C. and at the Input of the Indoor Unit the Pipework its 55 & 20 Deg C.
However I must of knocked the pipework a few weeks back & had a very slight leak on one of the fittings... I've nipped this up & checked everything tight with soapy water.. However temperatures inside are struggling to get above 20 degC & noticed that the outside evaporator only ices up at the bottom 1/3 & no higher( however i don't know if this is normal)... Would this be due to loss of coolant because pipe temperatures do seem pretty good I would think.. At 6dec C outside air temp yesterday the pipes at the Outdoor unit in Heat mode where 64deg C & 21Deg C respectively measured with a digital thermocouple.. Any help would be appreciated

Thats some serious DT's you're getting there. Where are you taking your measurements?
Is this an air to water unit?
What type of heat distribution system have you?

[sinewave]

It would seem you have answered your own question in that you've lost some refrigerant charge with your 'leak' which will result in loss of duty.

BTW Soapy water is not a good thing to use as a leak detector on refrigeration pipework.

I'd sugest you contact a contractor to check your charge and pipework integrity.


Which manufacturer is it?

[brizy]

Its a 12K BTU Unit Bergdorf, Use to heat my shed during winter, temperature reading taken with a digital thermocouple with the probe touching pipework 1. At the Outdoor Unit Couplings & 2 at the Indoor Unit Couplings

[Gary]

I take it this is an air to air heat pump, in which case the high temp pipe in heat mode would be the discharge line.

The increase in discharge line temp would seem to indicate an increase in superheat, which would indicate a shortage of refrigerant. Partial frosting of the outdoor coil would tend to confirm this.

[brizy]

Cheers Gary, thanks for the help with this...Looks like an engineer call out if thats the case... Anyone a rough guestimate looking at the Outdoor Unit ratings its 1080g of R410a thats required

[Gary]

Cheers Gary, thanks for the help with this...Looks like an engineer call out if thats the case... Anyone a rough guestimate looking at the Outdoor Unit ratings its 1080g of R410a thats required

If I were the engineer repairing your system, I would undo and redo your leak repair, recover and evacuate the system and charge with fresh refrigerant. Only then could I guarantee the repair.

[sinewave]

Tis the only way forward OP! :)