Replaced heat exchanger burned off all factory sent chemicals. Blocking supply to make sure no smoke went in location. Replaced rollout switch and RTU 3 now heating properly. Job complete.
RTU #2 is off and awaits a replacement heat exchanger. Darlene to check on the order status tomorrow. RTU #3, which also serves the front lobby was not operating because of a limit fault. I looked and found the blower belt shredded and off and I guess it pulled a lead off the limit switch when it snapped. I replaced the belt and put the wire back on the limit switch. I believe the belt was just a bad belt. I couldn’t see any burrs on the pulleys or misalignment opportunities. RTU #3 fired up and is operating normal.
Arrived onsite to inspected units for fall maintenance. Inspected all units in heat test mode verified proper order of operations. Documented all unit info and amp draws. Documented all findings. Found Unit #2 to have bad heat exchanger that is cracked and needs replacement. This Unit also has deteriorated heat rollout switch. Unit is shut down until Parts are replaced waiting qoute Unit #3 to have combustion motor with burnt wires needs replacement. This unit is still operational. Took picture and documented all findings 2 quotes
Up on arrival performed operational inspection. Changed all filters and belts, tested all units and checked electrical. All units working good at this time
On arrival found compressor and condenser off on control voltage, checked safety switches and both were closed. Reapplied power to see if 24v being lost somewhere else and system came on and was operating with very low suction pressure, head pressure normal. Checked blower and found fan spinning very slowly because belt was very worn and falling apart. Replaced belt and tested system. System now operating with normal pressures and temps, cooling properly. Materials used: 1 x A40 blower belt
Performed inspection of all rooftop units. Replaced all filters. Inspected heat exchangers, blowers, and coils, all clean. Checked capacitors and contactors, tightened electrical connections. Ran heat and checked operation. Let systems satisfy thermostats. Units operating normal. Customer still complaining about being cold in front yet thermostats are satisfying.
Upon arrival I spoke with receptionist and she informed me that front area was cold last night and into this morning. Found both thermostats in front reading 69, set for 72. Went to roof and found both units 1 and 2 operating at max capacity. Found normal heat rise on both systems. Checked gas pressures and found them to be in spec. Kept running systems and checked specs twice afterwards and found them to be identical so it doesn’t appear that either unit is faulting, just not keeping up. Verified all economizers are closed and not pulling in outdoor air. Units are heating as much as they can. Systems are all now 22 years old. Customer may want to get an estimate to see if they need to increase the unit size(s).
Found system running . Unit was running in first stage heat and not going into second stage due to a lose wire . Fixed connection and tested operations . Checked economizer and made sure it was closed . Return air 60 and supply air 84. Temp rise on machine is rated for 15-40 and we at 24 . Checked operations on second unit due to both reading 62 in front area and set for 72 . System is operating and just couldn’t keep up with other system running in first stage only .