Can you repair transformer 24v

Answer 1

Hi,

24 volt control Transformers come in all kinds of sizes and voltage options.

If you have a all electric system then chances are you have 230 volt A.C. primary to 24 V.A.C. secondary.

If you have a gas system I'm assuming 120 volt A.C. primary to 24 V.A.C. secondary output transformer.

The above two are in no case all there are out there but the most common in the H.V.A.C. field.

These small control transformers are typically rated in VA ratings.

Make sure your transformer is showing its full voltage potential reading under full load on the output 24volt A.C. side. If it is not , then you either have a transformer that is to small from some addition to your system or wrong transformer replacement in past. You can check the amperage output with a amproble if necessary on secondary side. It should not go above the name plate rating. If it does, check to see if your equipments literature or supplier & manufacture can tell you what original equipment was designed for this system.

Sometimes the transformer will hum when under heavy load. Whatever part of the system that started drawing power when this occurse is usually your culprit to your problem.

Transformers can just age and go bad. (OR just go bad period) if it hums alot then it has weakly wrapped windings which can cause insulation failure within the coil.

But please do remember most transformers get louder the closer they come to their nominal designed conditions.

Sometimes if your Amprobe will not pick up the small signal you can wrap a wire around the wire you are checking 10 times and connect at ends and it will magnify your reading x10 so you can see it on your amprobe.

Transformers usually really stink when they go down. They have a real sharp burned smell that stands out quiet strongly. So Use your nose.

Basically this is what you will see in most home situations:

central heat only=20 VA rating 24 volt transformer

central heat with cooling = 40 VA rating 24 volt transformer

Heat Pumps and dual fuel systems typically use =50va output ratings or sometimes 60 VA. because of all the extra devices they have to operate in the more complicated systems.

Remember any transformer should be seen and not heard if all is well.

Hope this helps: Jimiwane

Answer 2

To size a 24 volt transformer you have to work backwards from the load amperage. Small transformers are rated in VA(volt amps), for example if a doorbell chime draws 1.5 amps then the transformer needed will be 24 x 1.5 = 36 VA transformer. Since these transformers only come in specific sizes all was select the next biggest size up from what you need. In this case a 50 VA would be needed. The transformer rating usually advance by 25 VA at a time and then by 50 VA when the sizes get larger.