Fuse E 3A had burned when i turned to heating.

[vinhtito]

I had intallation new Goodman 13 seer 3 tons unit with heat pump R 410a. Condenser has 5 wirings. Themostart has 7 wiring. Indoor air handler has 5 wiring. Heating element 2 phases 10Kw. Cooling run great, but i had trouble with heating .Why the fuse of board control had burned when i turn to heating with 3 tons unit R410a? THANK YOU

[texas64]

Read literature that comes with indoor unit...it's in there!

[chilliwilly]

Does that control fuse feed the reversing/slide shuttle? Maybe check that out, try dissconnecting it then turning it onto the heat selection and see if it illiminates it.

[texas64]

OP isn't an engineer, but the end user. Note: "2 phases". Just saying....

[chilliwilly]

OP isn't an engineer, but the end user. Note: "2 phases". Just saying....

Well pointed out and I know what your saying, but I thought that you had a 2 phase service (240v) domestic/residential electrical service in North America.

[texas64]

We call it single phase 208/230/240 or three phase 208/230/240 or 480 volt. Just hate to see folk trying to save money on repairs and then turn around and really hurt themselves, someone else or their equipment, but especially themselves. My cousin died at 35 years crawling around an attic of a bar to help out with some construction and was electrocuted. Ever felt 24 volts when you are sweaty from head to toe? Ouch a bit, right?

[texas64]

Most of the USA manufactured units default to no power on the reversing valve for heat mode, should be no power there in heat mode unless it's in defrost mode.

[chilliwilly]

We call it single phase 208/230/240 or three phase 208/230/240 or 480 volt. Just hate to see folk trying to save money on repairs and then turn around and really hurt themselves, someone else or their equipment, but especially themselves. My cousin died at 35 years crawling around an attic of a bar to help out with some construction and was electrocuted. Ever felt 24 volts when you are sweaty from head to toe? Ouch a bit, right?

Sorry I wasn't trying to be funny and sorry to hear about your cousin. Did he have a heart condition then as 24 volts does seem very low for an electrocution? I have had many a belt off various voltages in damp conditions and dry conditons for more than one reason, but I have never felt 24 volts when I have been wet or dry. That is the voltage that modern fire alarms work off and sometimes the ancilliaries are outside.

I didn't realise that the OP wasn't an engineer/tech, I just assumed that he was foreign and working in the States due to the nature of his grammar. But yes when they try to save money messing with things they don't fully understand, it can be dangerous.

[chilliwilly]

Most of the USA manufactured units default to no power on the reversing valve for heat mode, should be no power there in heat mode unless it's in defrost mode.

I thought that maybe the shuttle reversing valve/actuator coil may have been faulty causing the control fuse to blow when it energised from cooling to reverse. As I know that the fridge side system shuts down until the cycle has completed.

[texas64]

No, my cousin didn't die of 24 volts. I was only saying that even 24 volts can feel jolty when we are wet and grounded, but I don't think that it would kill. Thanks for the concern. I just feel that with a lack of experience, a person could hurt themselves, just depends on the carelessness or lack of experience working around equipment. I think we have all experienced an "eye opener" once in our years of experience to make us much more respectful and cautious. Just saying...Cheers I think the poster should call out an engineer and observe and ask questions to learn what the cause is and observe the how the repairs are made in the correct and safe manner.

[Yuri B.]

24 Volts can kill, unfortunately, at least some who are more sensitive than the most are.
Its all extrremely situation and state dependant.

[vinhtito]

Thanks all brother.The result i just got that blue wiring must conect to comment of the themostat....