R22 TEV suitable to use on a 407c charge?

[danielt_smith]

Got a 407c pool heat pump factory fitted with a fixed position R22 thermal expansion valve. I’m getting intermittent flood-back and occasional high amps. I’ve since relocated bulb and insulated which has improved the situation.

22 and 407C have similar pressure temperature readings. Can someone advice if a R22 TX valve is interchangeable for use on a 407c charged unit?

[Iceman1956]

R22 Power Assemblys were used originally when R407C systems introduced in the UK, as R407C power assemblys were not available, usually you will need to adjust, to obtain the correct superheat. It can be a little trial and error but persevere and you should be able to get it set correctly.

[nike123]

R22 Power Assemblys were used originally when R407C systems introduced in the UK, as R407C power assemblys were not available, usually you will need to adjust, to obtain the correct superheat. It can be a little trial and error but persevere and you should be able to get it set correctly.


Got a 407c pool heat pump factory fitted with a fixed position R22 thermal expansion valve.

Check that post again!;)

[Iceman1956]

Answer is still the same, but action will be different. R22 Power Assembly can be used on R407C. Trial and error on Phial position should cure the problem, and get the superheat within range. Try some Heatsink compound between phial and pipe it may help

Not wanting to teach granny to suck eggs. but the phial position in relation to the pipesize is very important. Get this right and rest will follow.

[nike123]

Answer is still the same, but action will be different. R22 Power Assembly can be used on R407C. Trial and error on Phial position should cure the problem, and get the superheat within range. Try some Heatsink compound between phial and pipe it may help

Not wanting to teach granny to suck eggs. but the phial position in relation to the pipesize is very important. Get this right and rest will follow.

Generally TEV for R22 are set at 3-5K superheat. Superheat for R407 should be 6-8K. I don't see how phial placement could lead to increase of superheat.
If TEV is nonadjustable it cannot be adjusted for proper superheat and need to be changed with new one (preferabli wih R407C powerhead)

Check this article (http://www.temperzone.biz/tz%20Application%20Notice%200202.pdf)!

[danielt_smith]

R22 Power Assemblys were used originally when R407C systems introduced in the UK, as R407C power assemblys were not available, usually you will need to adjust, to obtain the correct superheat. It can be a little trial and error but persevere and you should be able to get it set correctly.
Thanks for the feed back.
Replacing old TEV with one with an adjustable setting. Will try with setting of 6-8K.
I am unsure of the term 'phial placement'. The bulb was at 12 o'clock on the pipe and I relocated to 8 o'clock if that's what is meant?

[nike123]

Thanks for the feed back.
Replacing old TEV with one with an adjustable setting. Will try with setting of 6-8K.
I am unsure of the term 'phial placement'. The bulb was at 12 o'clock on the pipe and I relocated to 8 o'clock if that's what is meant?

Phial=bulb

Bulb should be located as stated at instalation manual of TEV (like this one (http://www.ra.danfoss.com/TechnicalInfo/Literature/Manuals/01/DKRCCPIAA0C100.pdf)) and is usually between 1 and 4 o'clock (8 and 11 o'clock) depending on suction pipe size.

[tonyhavcr]

( don't see how phial placement could lead to increase of superheat.
If TEV is nonadjustable it cannot be adjusted for proper superheat)

I seen some will move the bulb closer to the evaporator I even it on the evaporator to decrease superheat or move it far as they can down stream to increase superheat

[HallsEngineer]

I think he meant a valve body that was brazed in rather than flared?

[Gary]

I’m getting intermittent flood-back...

How can we have a discussion of superheat without knowing what superheat you are getting? Where are the pressure and temperature measurements?