Constant Circulation

DL

Our house has a Tekmar Outdoor Reset 363 and Vitogas 050.
In the past, the owner had zones turn on an off using Honeywell zone valves.

Toying with the concept of constant circulation, I turned up all my thermostats (about 75 deg F) and the zone valves (9 zones) are open all the time. After 2 days the temp in each room seems fine.

Should I stay with constant circulation in all zones?

Benefits I see:

1. Probably better for my hardwood floors as cracks
developed this past winter probably due to sudden heat.

2. No water hammer noises from zone valves shutting down.


Concerns:

1. Will the Grunfos circulator pump be reliable to pump
all 9 zones 24 hours a day? Is it strong enough? (2800
square foot house, all in-floor radiant, indirect DHW)

2. Will my heating bill go up significantly?

3. If it works year round, should I disable my zone valves?
(apparently to prevent them from burning out one day)

4. Any other issues you can think of. Mainly reliability.

Thank You

Weezbo

without seeing it it sounds like the system in the field....

is balanced at this time ,keep an eye on it a few days. the gronfoss is on the injector? or a system pump? i think ,the circ pumps by grundfos are reliable.

DL

I'm not sure if the system is balanced or not. By 'balanced' I am assuming you mean that all the loops are emitting the right proportion of heat for the rooms.

After 2 days all seems fine but the weather has been relatively mild so I might just be lucky for now.

There are 4 Grundfos pumps in my system. One is the primary circulator, one is the pump for the whole house radiant, one is used as a variable speed injection(?), and one is the DHW pump.

I'm concerned that the whole house radiant circulator might be under strain pumping water to all 9 zones 24 hours a day.
Or, is this a fairly common thing to happen?

Constantin

Balance = Equal Loop Length

IIRC, a balanced radiant system is one where all the loops have the same flow resistance. One way to achieve this is equal loop lengths of equal internal diameter. For example, our basement will have 7 zones of 200 feet each, fed by 2 manifolds. Thus, you can simply have one pump deliver water to the whole zone instead of having individual pumps or regulating valves.

One of the benefits of radiant is that it does self-regulate to a degree... a colder room will elicit more heat transfer than a warmer one. Coil layout is probably the most important factor to ensure even floor and room temperature... hottest part of the coil on the exterior walls and all that.