With tremendous help from this forum (special thanks to Dana), I've managed to evolve my ideas of a new heating system to a single Mod Con and an indirect hot water heater. This is the first post I have made on this topic, so my concept is poorly formed at present.
I have installed PEX under cement board and will tile 30% of the house (mostly downstairs, some up). For the remainder, I am installing cast iron baseboard (sized for adequate heating at 135 deg water). There is also fished basement planned which will utilize radiant floor in a poured slab on rigid foam, but I leave this out of the discussion for now.
I have divided the system into a number of zones for two reasons. Because I am using mixed emitters I need different supply temperatures. Secondly, the future plan is to divide the house into two living units, each with upstairs and downstairs - so they require separate control.
Downstairs will have three zones. One for the radiant in the open concept kitchen/dining and includes bathroom and butler pantry. One zone will be for cast iron baseboard in double living room. One zone will be radiant for a small zone for the entry foyer with double height stair hall. The area can be closed off with doors and could be kept at 50 most of the winter.
Upstairs will have three or four zones.
Off the east stair one zone will be radiant for the walk-in closet and bathroom. One zone will have cast iron baseboard for the bedroom.
Off the west stair, probably combine both bedrooms and both bathrooms with cast iron baseboard on one zone and add a TVR to bed/bath with not thermostat. Or, put the bedrooms on separate zones.
I will need a zone for the indirect hot water tank too.
The boiler I am buying is Lochinvar 89000 BTU Output Knight High Efficiency Boiler w/ Fire Tube Heat Exchanger (Wall Mount) (NG). I felt these features relevant:
1. Three Boiler Setpoint Temperature InputsPlus Domestic Hot Water Prioritization.
2. Four Pump Control System Pump with Parameter for Continuous Operation Boiler Pump with Variable Speed Control Domestic Hot Water Pump Domestic Hot Water Recirculation
So, what is the key strategy to the setup here?
I was thinking of using Cross manifolds. I could use one for radiant and one for cast iron, and work with 2 temperatures? This way my zoning can work off the manifolds. Does this mean I don't need P/S piping? Also, I would need to tee-off the hot water coil zone before I mix down for the space heat? Or, would I not need to mix down because the 10:1 turndown ratio can send the right temp water to begin with?
This boiler has two one inch supplies and two returns (top set and bottom).
Related to radiant heat, the large kitchen zone has 3 homerunned sections, which I plan to run as one zone. Would it make more sense to tee them all into on 3/4" pipe to attach to the manifold instead of taking three spots (since they are all controlled by one thermostat)?
Should I add a floor sensor to the radiant on top of thermostats for room temp? It seems many do both.
I am certainly in a learning phase here for this system. I did install a used Peerless CI Propane boiler with 13 zones for another building. It has worked well for 8 years. But, I am approaching this project with more care and added complexity.
Shawn
I have installed PEX under cement board and will tile 30% of the house (mostly downstairs, some up). For the remainder, I am installing cast iron baseboard (sized for adequate heating at 135 deg water). There is also fished basement planned which will utilize radiant floor in a poured slab on rigid foam, but I leave this out of the discussion for now.
I have divided the system into a number of zones for two reasons. Because I am using mixed emitters I need different supply temperatures. Secondly, the future plan is to divide the house into two living units, each with upstairs and downstairs - so they require separate control.
Downstairs will have three zones. One for the radiant in the open concept kitchen/dining and includes bathroom and butler pantry. One zone will be for cast iron baseboard in double living room. One zone will be radiant for a small zone for the entry foyer with double height stair hall. The area can be closed off with doors and could be kept at 50 most of the winter.
Upstairs will have three or four zones.
Off the east stair one zone will be radiant for the walk-in closet and bathroom. One zone will have cast iron baseboard for the bedroom.
Off the west stair, probably combine both bedrooms and both bathrooms with cast iron baseboard on one zone and add a TVR to bed/bath with not thermostat. Or, put the bedrooms on separate zones.
I will need a zone for the indirect hot water tank too.
The boiler I am buying is Lochinvar 89000 BTU Output Knight High Efficiency Boiler w/ Fire Tube Heat Exchanger (Wall Mount) (NG). I felt these features relevant:
1. Three Boiler Setpoint Temperature InputsPlus Domestic Hot Water Prioritization.
2. Four Pump Control System Pump with Parameter for Continuous Operation Boiler Pump with Variable Speed Control Domestic Hot Water Pump Domestic Hot Water Recirculation
So, what is the key strategy to the setup here?
I was thinking of using Cross manifolds. I could use one for radiant and one for cast iron, and work with 2 temperatures? This way my zoning can work off the manifolds. Does this mean I don't need P/S piping? Also, I would need to tee-off the hot water coil zone before I mix down for the space heat? Or, would I not need to mix down because the 10:1 turndown ratio can send the right temp water to begin with?
This boiler has two one inch supplies and two returns (top set and bottom).
Related to radiant heat, the large kitchen zone has 3 homerunned sections, which I plan to run as one zone. Would it make more sense to tee them all into on 3/4" pipe to attach to the manifold instead of taking three spots (since they are all controlled by one thermostat)?
Should I add a floor sensor to the radiant on top of thermostats for room temp? It seems many do both.
I am certainly in a learning phase here for this system. I did install a used Peerless CI Propane boiler with 13 zones for another building. It has worked well for 8 years. But, I am approaching this project with more care and added complexity.
Shawn