Heating not working on split system what is the problem?

Hello,

I'm a fridgy and i've only done install my whole career im now moving out and doing a bit of service work as well, i had a customer call me and ask me to have a look at their split system that is not working in heating mode. I was just wondering what you guys would think the problem is give the details i was given?
I have a fair idea of the problem but i just want to what you guys make of it and what you would first look for once arriving at the job.

It's a reverse cycle split system and it works fine on cooling but once it is switched over to heating the compressor kicks in and runs but the indoor unit only blows ambient air................that's all the details i was given.

Any help would be great :)

First and most important, is the controller set to heat and to a temp above room ambient? You know what customers are like.
Second, is it above 10degC outside? Some splits wont work below this.
Third, is the reversing valve working?
Fourth, discharge temp, hows the gas charge?

This should get you on your way

Eggs

Quote:

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Originally Posted by eggs

First and most important, is the controller set to heat and to a temp above room ambient? You know what customers are like.
Second, is it above 10degC outside? Some splits wont work below this.
Third, is the reversing valve working?
Fourth, discharge temp, hows the gas charge?

This should get you on your way

Eggs

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Spot on Eggs,all he has to do next is to follow your advise and i am absolutely sure it is one of the mentioned.:D

Hello,

Thanks for the replies sorry i forgot some of those details..........yes it is set on heating and it is above 10deg outside.

My guess without going to the job and given the information above was reversing valve.

What is the best way to know if the reversing valve is stuffed? just listen to see if its working and feel the pipes? is there any special requirements in changing the R/V?

Also will my local heatcreaft carry a replacement or will i need to contact the units manufacturer?

Ok just got some more info..........
It is a carrier unit when on heating the compressor runs and the outdoor units fan blows cold air (so the reversing valve is working true?)
They have told me that the indoor unit only blows air really softly if any and is at a ambient temperature.

I was also told that they actually haven't tried it on cooling as of yet.

The unit is 5 years old.

Any Ideas?

any ides guys?

Get yourself to site never try and fix a problem before you have seen the job, could be something really simple like a blocked filter.

Keep us up to date on how you get on.

Regards


PP

Not much to add after all the ideas but a few things.

Check pressures, discharge and suction, unit might have lost some charge.
feel by hand the pipes going out of the 4 way valve, you want to feel cold and sweaty suction and real hot discharge.

Look for frost signs on the bottom out side coil.

I've had a couple of heat pumps over the last year or so that have had stuck reversing valves due to being used solely on one setting.

Switch off power completley and give the valve a 'measured' smack with the handle of a screwdriver etc.

Switch back on and all may be well! :D


If not, hit it harder! :(

Quote:

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Originally Posted by sinewave

I've had a couple of heat pumps over the last year or so that have had stuck reversing valves due to being used solely on one setting.

Switch off power completley and give the valve a 'measured' smack with the handle of a screwdriver etc.

Switch back on and all may be well! :D


If not, hit it harder! :(

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Do make sure that the screwdriver has been calibrated though:D

Oh aye, forgot that bit!


:)