Business ProfileforAbacus Plumbing, Air Conditioning & Electrical

My downstairs ac and heater placed by Abacus HVAC has been broken since early December 2023, purchased along w the upstairs ac and heater in October 2018 . The upstairs ac failed again in May 2023 4.5 yrs later and that ac/heat system was replaced at my expense. They said it wasn’t under warranty and I had no reason to think they would be mistaken so I did what they recommended and replaced the 4.5 yr unit in the walk up attic and also replaced a condenser outside.The upstairs (6 month old)system failed on first heater use in Nov 23 and was repaired at Abacus’ expense. The downstairs (5yr 2 months old)heater failed a few days later . They came out again and are waiting on a heat exchanger to repair my 5 yr old downstairs system.They estimated a 3000,00 dollar repair.According to my invoice, the heat exchanger had a 20yr warranty. I have paid approximately 33,000 dollars for their hvac work so far. My house is 1800 sq ft. 1.5 bathrooms built in 1940. They say I should have called them more often for system checks in order for them to fix this under warranty. I don’t see this condition in their several page contracts. I paid for the upstairs unit replacement at 4.5 yrs because I trusted them but when the downstairs unit failed at 5yrs 2 months I wonder if the system was installed incorrectly in 2018. I sent a letter to the company president by certified return receipt mail w receipt returned to me on Jan 19th. Please see download below which is my letter to Abacus with invoices. They have no time estimate on the repairs as recently as this past Friday Jan 19th. and it has been 2 months of heater problems. Should they replace the 5 yr old heater/ac unit downstairs under warranty if it is unable to be repaired in a timely manner? I don’t know if the Oct.2018 system was inspected by the city of Houston post installation as was done inMay 2023. When the Spring comes there will be no ac either downstairs as thermostat screen is blank. Please advise.