Baseboard Heating Problem

D. Rand

I have a Viessmann boiler with three heating zones and one domestic Indirect Tank. The downstairs zone does not seem to come up to temperature like the other two zones. There is approximately 52' of baseboard on the first floor zone. There does not seem to be much convection coming up from the baseboard. It is off the floor approx. 1" to 1-1/2". The sheer curtains above the baseboard does not move at all.

The house only comes up to around 68 degrees on a 5 to 10 degree night. The heatloss has been recalculated by two different people and there seems to be enough. Any thoughts
on what I can look for????

bigugh_4

Heat travels upon

the flow of water in the BB. That given, is the flow of water in the BB large enough. Are there valves that could be closed? Is there a single pump ? what is the Cv of the zone valve ? 52 ft of BB should give you 41,600 btu's at 180*F water temp. is that temp getting to the BB ? Is the outlet of the BB 160*F ? If it is less than that you need to increase the flow? . Is that room calculated to need just 41.600 btu's at a 0*F outside temp ? Just priming the thought process here as I cannot see your situation. You'd need 4+ gallons per minute through that 52' alone to get that BB putting out the max it is supposed to. bigugh

Joe_8

I guess the best way to approach this is to ask a few questions?

1. What temperature are you running the boiler at?
2. What is the differential temperature from start-up to shut down?
3. Are the lines air free?
4. Is the circulator properly sized?
5. Is the circulator operating properly?
6. Are there circulators controlling each zone, and if so,are they working correctly and supplied with enough amps to run at peak?
7. Are the zones controlled by zone valves? Are they working properly?
8. Flo-checks? If so, are they opened during operation of the corresponding circulator?
9. Are there any valves shutoff?
10. Are the thermostat heat anticipators set correctly?
11. Is there enough pressure in the system?
12. Is there enough flow of water through the system? I have actually seen where the boiler outlet was clogged with a plastic thread protector.

I guess the bottom line is to break the systems systems down to their basics and begin the process of elimination. If the system is properly sized as you say, then the problem must lie within the operation of the sub-systems.

Good luck.