Heating, Air Conditioning, Fridge, HVAC/Bryany model 355 MAV problem


We have a Bryant model 355 MAV furnace with a bryant evolution system thermostat. After turning off and then on power to reset it, it will heat up to thermostat set point temp and turn off. However when the temp drops it will not restart. Inside LED's them alternately flast green and amber but with no amber diagnostics code. If I rurn off main power again for a few minutes it will do all of the above again?
Any hints on what can be wrong? My local rep says it must be the main board and they will get back to me with a price on Wednesday


To eliminate the t-stat,and stat wire as a source, pull wires R W G off at your furnace ( stat wires from your t-stat ) jumper R to W to G let system heat for 10 minutes, remove while power is still on furnace. let it cycle off ,including blower fan. If all is well then rehook to those points and see if it starts another cycle without locking out, then your board is OK .if not then  your rep. says it's the board,then replace the board.They are suppose to be the experts, make sure you have a good ground also , if your board or anywhere in your furnace has a ground wire verify it makes  a good ground.Your power to your stat is 24 volt ac ,so it's not like your going to get shocked.

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40+ years diversified experience.An HVAC/Refrigeration Self Employed Contractor since 1986. NATE Certifield. Answer questions pertaining to Residential and Commercial Air Conditioning , Warm Air Heating, Heat Pump systems.Mechanical and Electrical troubleshooting of these systems.Be as detailed as possible when describing problem.Packaged unit or split systems.No appliance questions.


Installation and Troubleshooting, Mechanical and Electrical, in following areas, Refrigeration ( Walk In and Reach In Coolers and Freezers ) Commercial Roof Top and Packaged Heating/Cooling ( Natural Gas,Propane, Electric, and Heat Pumps ) Computer Room Air Conditoning Systems,Commercial Residential Packaged and Split Systems Air Conditoning and Heat Pumps.Warm Air Oil , Natural and Propane Gas Heating systems.

Graduated from Private Technical School in 1975. An HVAC/Refrigeration Contractor . Have Unlimited Heating/Piping and Cooling Contractor License.Limited Sheetmetal Contractors License.NATE Certifield. York Certifield Master Heat Pump Technician 1986. Served 33 years combination Active Duty Air Force , Air Force Reserves and Air National Guard in the HVAC/Refrigeration Shop/Mechanical Shop. Troubleshooting/Installing HVAC/Refrigeration Equiptment Worldwide. Retiring in 2003 as a Senior NCO ,and a Mechanical Superintendent.

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