This is a 10-year old carrier rooftop packaged HV AC unit that heats and cools the dining rooms of a restaurant. it has an electronic programmable thermostat on the wall of the dining room, and runs on 208 volt 3-phase power, with gas heat, and a 1.5 horsepower squirrel cage belt driven fan.. The restaurant closed about 3 months ago, and the new tenants are getting ready to open a new restaurant next week. The building is in Minnesota. the tenant called me a couple weeks ago and said that heat wasn't working. I told them to call an HV AC company and gave them a name and number. They called me Tuesday night this week and said that they still didn't have heat, that they hadn't been able to get anybody to come out and look at it and they had called three different places. We had gone through a cold snap where it was 10 or 20 below and they didn't have heat, and now a sprinkler head for the fire protection system was dripping because it probably froze. So I called up a different company and they came out after hours Tuesday night and called me up from the restaurant and said that there is a safety gas valve lockout that is part of the fire prevention system and it was shut off. So he pressed the reset button as well as check into unit for clean filters and a good belt and the unit started up and was making heat. He charged me $365 and left. The next morning, yesterday, the tenant called and said it was cold in there and that the heater wasn't working. I went over there and met with them, and it was cold in there, but they had a salamander kerosene heater running in there. they told me that they had had two different contractors out to look at it, and neither one could fix it, but they both charged them money. So now we have a bit of an inconsistency in the story, because over the phone they said nobody would come out. I had the tenant show me this gas lockout safety thing. It was an electric enclosure on the kitchen wall with a reset button, and it was connected to another box that had a relay in it that was buzzing. I asked him if it needed to be reset again. He said when it's working right it buzzes and it was buzzing now, so it had to be good i pressed the reset button and it it felt like a magnetic switch that was already engaged so it didn't make any difference, it was still buzzing, the button didn't feel like it actually did anything. He showed me what he had been doing in the restaurant as far as remodeling and cleaning to get it ready for reopening, and within a half an hour the rooftop heater came on by itself. I had the tenant showed me the thermostat and talked to him about if he knew how to operate it. He assured me that he did and that it was calling for heat, and had been calling for heat even when the restaurant was cold. Then i left the site and I called the company again and they sent the same guy out. And after an hour or so he called me and said that he thinks the unit is locking out on high limit, due to poor airflow. He did not say, and I did not think to ask, if he had looked at the circuit board on the unit to read the flashing light codes. I thought about that later, and I would think if he had done that he would have told me about it. He said he measured the amps at the motor and got 2 amps and the nameplate full load amps was six. So he wanted to put in a new motor, new capacitors, and a new belt for $1,750. I asked him if the unit locked out on high limit how did it started self up again hours later? He said that he guessed that the tenants had reset it somehow. at this point I was a little skeptical, and didn't want to spend $1,700 based on a guess. He said that he wasn't sure if it was the motor and the capacitors that were the problem, or just the capacitors, but it was probably the motor. I asked him what the capacitors were, start capacitors, or run capacitors. He said they were start capacitors. I asked him what size motor it was because I was thinking the price tag was pretty high as well. He told me you wasn't sure he thought 6 horsepower. I asked him to check it for me so he went back up on the roof and looked at it and called me back and said it was 1.5 horse Power. I told him I was reluctant to spend that much money based on a guess and asked if he could guarantee that this would solve the problem. at this point he suggested that maybe I would want to start with replacing the capacitors only because it would cost less. I asked him if they were start capacitors, and the motor was starting and running, how would that affect the RPM of the motor once it was up and running? He said good point. At this point I was really losing confidence in him. I told him I was going to get a second quote and to pack up and leave and I would get back to him. He charged me $95 for the call. I'm thinking this morning I'm going to tell the tenant to put new batteries in the thermostat, to download Emmanuel from the thermostat from the internet., study it didn't make a hundred percent certain that this thing is always calling for heat and that it is not shutting off due to some program. And I'm wondering if this motor failure Siri holds water. after the tenant verifies the thermostat is working properly, I'll probably go over on the roof and look and see if there's a circuit board on this unit and if there's any diagnostics lights lit up.
looking for suggestions, I don't want to throw away a bunch of money on a new motor that it doesn't need. Once it's up and running, and the restaurant is open, it is 100% the tenant's responsibility. But I'm on the hook for it until then. Thanks