I replaced our old oil hot water base board furnace with a energy efficient gas furnace. It's been two yrs it has been in and what is happining is the house is a split level so the thermstat is on the 2nd fl. The bedrooms on the upper part of the house are OK along with the 2nd fl. The problem is the downstairs three rms are cold and there is no way I can run or change to a 2 zone system. The baseboard system is a monoflow system so it is one big loop. It seems that the heated water goes to the upstairs first and by the time it is circulated to the bottom floor the thermastat is satisfied and the baseboads downstairs just get a little warm and the furnace shuts down. There are valves on the baseboards on some of the baseboards upstairs but I tried to close one and I think it broke off so it didn't close being the system is over 50 yrs old. Any help would be greatly appriciated.
Thank you
Ron .