josephm8777
08-19-2006, 11:24 AM
Im a tech from southern maryland and having a problem with a new unico blower hooked to a lennox heat pump. The problem is that it wont cool. It will keep the 1st floor 74 during the day and only down to 72 at night. Homeowner wants it 70.
Heres the background. Two systems, one up one down. 2.5 ton up and it was a 2 ton down. 2.5 ton up is cooling great and has subcooling and superheat both in the 20 degree range. The 2 ton down had 11 subcooling and 14 superheat. Just about perfect. Well it wouldnt cool. So Unico says there blowers are only removing 10000 btuh. Not the normal 12000 so we took out the 2 ton and put in a 2.5 and it still wont cool. The funny thing is that its doing very close to the same thing the upstairs is doing. High superheat and subcooling. Ive got a 56 psi suction and a 200 head. When you add freon the suction pressure drops. Pulling the april aire filter door off does nothing, disconnecting the supply does nothing. Both system are in the attic. The downstairs supply snake down through closets and such. The txv is working weve replaced it and heated it cooled it, to test it. We are getting a 22 degree split. But it just wont cool. I think if I could get that suction up to around 65 it would work. I think that the coil is staying so cold it wont pull the humidty out. The upstairs system the suction is about 65 and the head is about 250-275. But the downstairs if you add freon the head goes up but the suction just wont go up with it. And I dont think its a restriction because the 2 ton we had on it, the refrigeration system was spot on.
Any help would be appreciated.
Heres the background. Two systems, one up one down. 2.5 ton up and it was a 2 ton down. 2.5 ton up is cooling great and has subcooling and superheat both in the 20 degree range. The 2 ton down had 11 subcooling and 14 superheat. Just about perfect. Well it wouldnt cool. So Unico says there blowers are only removing 10000 btuh. Not the normal 12000 so we took out the 2 ton and put in a 2.5 and it still wont cool. The funny thing is that its doing very close to the same thing the upstairs is doing. High superheat and subcooling. Ive got a 56 psi suction and a 200 head. When you add freon the suction pressure drops. Pulling the april aire filter door off does nothing, disconnecting the supply does nothing. Both system are in the attic. The downstairs supply snake down through closets and such. The txv is working weve replaced it and heated it cooled it, to test it. We are getting a 22 degree split. But it just wont cool. I think if I could get that suction up to around 65 it would work. I think that the coil is staying so cold it wont pull the humidty out. The upstairs system the suction is about 65 and the head is about 250-275. But the downstairs if you add freon the head goes up but the suction just wont go up with it. And I dont think its a restriction because the 2 ton we had on it, the refrigeration system was spot on.
Any help would be appreciated.