Anyone do domestic splits and had a stuck service valve?

[paul_h]

Had a few of these, and no matter how I try, I can't get the service valve open (4mm hex type)
I've heated them up, used the longest kex key I have, bashed it etc.
It's such a pain to reclaim and weld in a new valve for a DOA unit with such a simple problem.
Manufacturers want us to try inpact drivers on them. I've found a impact driver that takes 1/2" sockets or 5/16" bits.
But I can't find any 4mm hex - 5/16 bit drives, or any 1/2" socket 4mm hex (most things under 5mm seem to only come in 3/8" sockets)
Before I spend a whole day looking for these things,(well I think I already have :( ), has anyone used one of these to unloosen a stuck valve successfully? Do you know of any australian sellers of the magic bits (or intenational sellers that ship overseas cheaply ;) )

[robin r33 gtr]

Iv had this and use a 3/8 rachet with a allen socket.

[monkey spanners]

Ive had this and ended up using a blow lamp, alan key and a rubber mallet to undo the valve. In retrospect i suspect that i had distorted the valve body by using the valve cap to steady the valve as i was tightening the flare nut.

Jon

[Abe]

Had a few of these, and no matter how I try, I can't get the service valve open (4mm hex type)
I've heated them up, used the longest kex key I have, bashed it etc.
)

Its something Ive never come across, but am thinking, are these old outdoor units that have been in service or these new unit ?

Cos, if they are new, wouldnt cooling them be better then heating the, ?

I was watching a prog on the Buj Al Arab hotel in Dubai, other night, and they were talking how those massive stabaliser cross beams expand in the heat.......now in the Oz heat are the valves expanding so much that become impossible to prize open ?

Just a thought

[paul_h]

Its something Ive never come across, but am thinking, are these old outdoor units that have been in service or these new unit ?

Cos, if they are new, wouldnt cooling them be better then heating the, ?

I was watching a prog on the Buj Al Arab hotel in Dubai, other night, and they were talking how those massive stabaliser cross beams expand in the heat.......now in the Oz heat are the valves expanding so much that become impossible to prize open ?

Just a thoughtThese are dead on arrival, the installers pipe them up and find that they can't open the valves. it's not ambient temp related as I get as much in winter that I do in summer. It could be related to what monkey spanner said, (installer warping the valve when tightening the flare). But I doubt it, I've had to reflare and/or tighten it the same way and never had a stuck valve. I've also had a heap of valves that don't seal when closed, enough to make me think this is a manufacturing issue.
Cooling wouldn't work as the outside would contract, tightening against the valve key.

[expat]

I agree with Robin R33. I also use a 3/8 ratchet. If they seem too tight you sometimes have to crack them like you do wheel nuts. You apply some pressure then give it a quick extra push, careful though.

Monkey spanners
I hold onto the valve when Im tightening the nuts as well. Never thought I might distort it though, have to look out for that in the future;)

As for heating it, I'm not quite sure what your trying to do. Expand the body of the valve around the valve itself:confused:

[paul_h]

oh well, I guess I'll try to find a 4mm hex 3/8" socket then. It seems to be the most available size and that's two who have said it worked. Though I wouldn't use a ratchet, that's not what they are made for, I'll try to find a 3/8" breaker bar.

As far as heating up the valve, have you ever heard of heating up a stuck nut with oxy/turbo torch? The outside part expands first, therefore in the stuck nut senerio, it becomes looser on the bolt. In that way of thinking I thought heating it up might help. Maybe it wouldn't and the outer valve housing would expand equally inwards towards the valve key and not help at all. Lets just call it desperation, it's a DOA unit, on a roof, and you are imagining have to haul up the oxy, vac pump etc onto this roof for a $6 POS part. You want to try anything.

[expat]

I used to have to heat up big nuts (I know the first part of this scentence sounds dodgey) on lorry trailer springs until they were orange to get them to budge sometimes.

But I was thinking that brass would transmit the heat to the interior of the valve too quickly to be of benefit, but then... you've gotta try everything.

[expat]

Just another thought. If you apply pressure to your breaker bar and then tap the head of it with a small hammer this will have the effect of the impact driver.

(sorry, used to be in agriculture. To us hammers were called universal adjusters)

[paul_h]

Well I bought a 1/2" socket impact driver. It came with an adapter for 5/16" bits, with philips and slotted 5/16" bits.
So I started the hunt for a 5/16" to 4mm hex bit, and no one sells any 5/16" bits, even though every store I went to sold impact drivers with 5/16" bit adapters only.
So I bought a 3/8" to 4mm hex socket you guys said you've used, and a 1/2" to 3/8" socket adapter, meaning I can use the 4mm hex socket on my impact driver and my 1/2" breaker bar.
It beats a reclaim, replace service valve and recharge job anyday if it works.

[superswill]

ive a great set of long allen keys from rpw comes in a kit with a handle,always works for me or theres the BIG hammmer!!!!

[taz24]

Just another thought. If you apply pressure to your breaker bar and then tap the head of it with a small hammer this will have the effect of the impact driver.

(sorry, used to be in agriculture. To us hammers were called universal adjusters)

And a small hammer should weigh less than 12lbs.:D

taz