I am wanting some insight on making a transition from installing to service work, if anyone would be willing to enlighten me.

I have been working for a company for 3 and a half years with no previous expierience and go to college part time to.
(For HVAC) I have learned a great deal about installations and am now a lead installer for this company. I supervise installations of 2 ton splits clear up to 25 RTU's. With multiple jobs going on at once, and usally its multiple zones or systems. Well, anyhow my position there has taken me down the road towards Project Management, and I'm not sure that is the road I want to go down right now. I have not had the chance to stretch my legs into much service work at all and was wondering if maybe now's the time to try and do this before I become to involved in this company, being there project manager (field supervisor)?

So I have been looking into the job market for service work, and have found a company that is interested in me. I am going to an interview there in 3 days, and was wondering if someone could help guide me because this is a difficult decision. This other company does commercial restaurnt refrigeration and equipment repair (hot side). So this is a new ball park for me, but a good place to get service expierience......

So I hope someone may be able to help.