is ther txv ?

[4uzindian]

i'm back for a question. in the attic is the comfort maker air handler unit. the model number is EXM36F19A1 .it was installed in 1998.does thi hae a txv valve in it. i can't seem to locate any info on this .also is the ev coil inside made by the goodman comp. ? another tech came out and lowered the suction line presure down to 75 degrees. it still not blowing cold air. the tech wanted to know if there was a txv valve.

[jumptrout51]

A txv looks like this and is external to the evaporator coil.
If a tech looked at your system and did not know if it has a txv he is a very poor tech.
A Comfortmaker ah will have a Comfortmaker specific coil.

[4uzindian]

the tech did not take off the cover of the unit to look. i was asking for myself. since my unit has one do you know if it's adjustable. just curious.

[JWWebster]

http://www.americanhvacparts.com/p-11656-2-ton-to-3-ton-direct-factory-replacement-r-22-expansion-valve-icp.aspx

[JWWebster]

Freon flows through this valve all the time the machine is running. The way this puppy works is it's temp bulb basically gets attached to the suction line so it can FEEL the line temp. As the freon flows by the bulb the valve opens or closes allowing more or less freon to flow. It is very important that the bulb is attached firmly to the line and sealed up wrapped tightly on that line.

[AJ]

Do you just clamp the bulb of the valve to the suction line with hose clamps or a plastic wire tie or is there a special way it should be attached?

What is used to wrap it up with once the bulb is attached?

I'm no HVAC guy as you can tell.

[JWWebster]

Wrap it in adhesive rubbertex then foil tape. It must be tight and sealed.

[4uzindian]

thank you for the reply. the link you displayed showed as a run time error. that does't matter. iv'e read many explanations on txv valve operation so i know what your saying. what i found but forgot the site name is the comfortmaker unit i have has a built in txv.what ever that means.it has a bulb or it does't have a bulb.do you know if this might have a bulb .this is something i could check myself.built in tells me you can't replace it. i googled  comfortmaker  exm36f19a1 info . i tapped on the first site which was americanhvacparts.com. a picture of a txv that replaces a lot of models includeing mine. confused. i 'll have to take off the side panel and take a look i guess. built in tells me it can't be replaced. you would have replace the the entire evap coil.

[JWWebster]

According to the link above you have a TXV with an external equalizer which means:
In a system with a relatively small evaporator, the pressure drop across that evaporator is so small you can assume it is zero. Therefore, the TXV outlet pressure and evaporator outlet pressure are equal. By drilling a small bleed passage between the underside of the diaphragm and the outlet of the valve, you can sense the pressure internally and eliminate the need for an external connection. Valves produced in this manner are termed internally equalized valves. In most a/c systems, the evaporators are quite large and, therefore, have significant pressure drop across them. For the TXV to sense the evaporator outlet pressure, a separate line is needed from the suction line (near the TXV bulb location) to the external equalizer connection on the valve body. If a distributor is used to supply refrigerant to various evaporator circuits, an externally equalized valve must be used. Distributors typically have between 15 PSI and 30 PSI pressure drop across them. Hence, use them only with externally equalized valves.
http://www.hvacfun.com/a-everything-you-need-to-know-about-txv.htm

[4uzindian]

whatever. that was out of my league. leae that for now... my origanal unit had a .067 restrictor /piston/pin i the small line schrader valve out side. i got today from aircre a pdf download of a lot of specs for the new unit i have outside.i should get to it today or tommorow to see if this has the same size restrictor. let you know what i find. maybe that's why it's not cold.other problems today. water up to floor level  in drain pipe  in small bathroom when i removed toilet.it was leaking on floor in cellar. i power vaced alli  the water in pipe i could get to .should i do roto rooter or use instant power maineline cleaner from home depot ? it's the back of system in front of is other toilet it works then cellar sink it flows then out to street line. roto rooter is coming at 12:00 to 2:00 tommorow the 19th.

[JWWebster]

Got any kids? Reason I asked is my grandbaby stuck a toy down the toilet and it got hung in the pipe. That was a lot of fun. 

[4uzindian]

looked at the download info on the aircore unit but ther was no mention of the the size of the restrictor.i'll check more sites and maybe find what i'm looking for.mr. cheap came the smorning and cleaned out the mainline drain. that's done with.took the cleaner back to home depot for a refund. back to the restrictor valve in small line in outside unit. if the arcoaire unit has different size restrictor than the origanal comfortmaker .067 could this affect the temperture output.

[4uzindian]

didn't check any sites no time today. does that restrictor have any thing to do do with the air temp ?

[JWWebster]

You must have a mismatch

[4uzindian]

if it's a mismatch that means it could have an affect on the temp output as you say. so i will con tact the guys that installed it. i'll try to get them to check without having to pay for this checkup. i'll post to let you know whats up.