Mitsi Fault

[Slim R410a]

Hi,

Breify looked at system not cooling today, its a twin split with a PUH-5... outdoor on R22.

The filters on the 2 cassettes were blocked so washed them out but was getting a P8 (abnormal discharge temp?) fault on the remote.

Put my gauges on the suction schreader, had a head pressure of around 7.5bar, and ran the sytem in test mode. Compressor ran, air off condenser was just ambient, liquid line was sweating, suction was around 1.5 bar. So first thoughts were that it was undercharged. On closing of manifold gauge after adding some vapour, the pressure remained at around 7.5bar again, with the comp still running.

Could there be a blockage somewhere? The suction service valve is after the 4-way reversing valve if that helps?

[andy bailess]

Hi slim
we have had reversing valves stick half giving the fault you have idicated,i suggest you switch the unit off a lightly tap the body of the valve or energise the coil a couple of times to see if it seats properly.

[Slim R410a]

Thanks for the help,

I tried tapping the valve whilst it was running but not while it wasnt. When you say energise the coil I presume you mean ask it to heat, should there be 240v on the coil when it asks for heat mode?

[andy bailess]

Thanks for the help,

I tried tapping the valve whilst it was running but not while it wasnt. When you say energise the coil I presume you mean ask it to heat, should there be 240v on the coil when it asks for heat mode?

When your next passing a fridge wholesaler pop in and by a coil magnet,they fit most sol valves and of course you dont need to keep running to the outdoor unit to see if its gone on heating mode.Simple idea and a useful tool for engineers i think its called a fridgemag?

[Temprite]

Thanks for the help,

I tried tapping the valve whilst it was running but not while it wasnt. When you say energise the coil I presume you mean ask it to heat, should there be 240v on the coil when it asks for heat mode?

Some units energise the coil on cooling.