Mono Flow T's (Spacing)

Neil_5

I was reading the mono flow article here, and it mentioned that the space between the Ts should be the lenghth of the radiator/baseboard.

I have convectors, but one baseboard in the kitchen that is 5 feet long, however in the basement I can see that mono flow Ts are only 4 inches apart. Would this affect my flow thru the baseboard?

Neil

Uni R

Yes Neil

I'm not sure of the degree, but it would decrease the flow of the kitchen branch because of the close spacing between the tees. Do you have adequate heat in the kitchen? Is the kitchen at the beginning of the main? If so, maybe it was done like that to balance the heat.

Neil_5

The kitchen is second on the branch so you are right, back in 1955 when they design it they probably space it close .. however, back then the kitchen door was a regular door, now the house have a patio door which being all glass makes the room a bit cold, I was thinking of replacing the baseboard with hi-output baseboard, but now I can also space the Ts a little bit further.

Thanks,
Neil

Uni R

Of all the tools...

Wouldn't it be nice to have some kind of small shoot at the pipe flow meter? You aim it at a pipe, it gives you the flow. Just like the IR thermometers. I think there is a small ultrasonic thing available but not for the $200 I would want to spend on it. Then you could see what the flow is in that branch versus the others. What size piping do you have for the branch and the mains?

Neil_5

Mains

The main is 1" or maybe 1.25"? and the branch off is 1/2"

I will definitely move the Ts apart and install Hi-output baseboard, in that way I can run a lower water temp.

jim sokolovic

Or, you could...

install a ball valve between the tees. I'm assuming that the pump can overcome the slight increase of restriction. This way you won't be guessing at the right tee spacing to get the right heat output. Use a full port valve, start with it full open and close it down gradually until the right overall comfort is found. Maybe remove the handle when satisfied, to prevent someone from closing it or ruining your setting?

Neil_5

Would this method affect the flow down the main line for the other units?

Could this method be used in more than a few places to increase output (flow) with other convectors?

Uni R

Uni R

Jim's right!

That's what I was building up to with my questions on pipe sizing...


I was going to suggest the same thing, although I would take the one diverter tee out and replace it with a regular tee and then put a globe valve in between the two tees. Also Neil, save the Monoflo, don't let it rust. The cast iron models are long gone from supplier shelves. A globe valve might be better for throttling than a ball valve in this application.

Uni R

Neil

You can but if you have to do it to very many of your convectors somethings wrong. If that's the case, you may as well pipe in a manifold setup or reverse return.


Putting more BTUs into the kitchen with a valve shouldn't affect things too much since most of the convectors follow.

Neil_5

diff

whats the diff btw a glove and ball valve?

Actually I just have one convector in a den (seated on slab) with 3 big windoes and garage on one side that is normally a bit chilly. Windows are good, fixed all drafts, was wondering how I can increase the temp in that room. Although when the boiler temp > 185 that room is ok, but when the reset sets it in the low 150s that room is a bit cold.

Uni R

Valves

Ball valves were designed primarily to be on or off. They allow full flow and do a complete shutoff. Globe valves are designed to throttle with less disturbance to the flow of water. Gate valves often leak in time and aren't nearly as bulletproof but in this application they are better suited although either could be used.

Neil_5

Pipe Size

What if I increase the pipe size from the main to the baseboard, would this increase my flow rate?

Uni R

Marginally

However, if you get too much flow through the baseboard, you'll hear it.

Neil_5

Convectors

Inside of the convectors are dark, and the ones against the outside wall are cold when the temp dips, would there be any gain if I place duct insulation on the wall side of the cabinet of the convectors that are recessed into the wall? would this keep the cold back and reflect the warm air out thru the vents instead of mixing warm air with a cold back cabinet?

jim sokolovic

As far as the valve type/number...

A globe valve might have too much restriction - and give you too much flow at the baseboard, even in it's fully open position. Adding more valves, at the other convectors, might also be too much restriction on your overall system - and require a larger capacity pump. And you will have alot of balancing to do. Once again, I'm making assumptions - but you have to be cautious on these changes.

Jason_13

Tee spacing

The spacing of the tee's is a critical part of the installation. If you increase the tee spacing it will increase the flow through the kitchen radiation. The idea of tee spacing is to create more resistance between the tee's then the radiation and connected piping. This will force the water at a greater flow rate through the radiation. Increase flow and increase btu output.
When the door was replaced with a glass door it would have increased the heat loss for the kitchen. It might be a good idea to do a new heat loss for the kitchen and see if the existing radiation is enough. I would assume it is due to most homes are over-radiated.
I hope this is of some assistance in resolving you problem.

Neil_5

Heat Loss

Shows I need 12 feet of baseboard, I currently have 5 feet, my goal will be to increase the space between the Ts and replace the standard baseboard with Hi-output baseboard to get the proper amount of BTU in the kitchen.

Thanks for the infomation.

Neil

jon_6

spacing

your spacing should be no less than 18 inches apart and a venturi on the return side of the baseboard

S Milne

Neil

I have come across very few of the 50's monoflow tee designs that where way off design. Many of them have been bastardised by plumbers who did'nt understand the system. Are you sure that the two tee's you are looking at go to the same baseboard ? Is there a second floor ?

With a mono-flow design the tee's can be as close as 18" and still work fine.

Scott

Neil_5

System is in tact, no modification except when they updated the bathroom and kitchen they replaced the convectors with baseboard. Being the kitchen is the 2nd unit on the line from the boiler, they may have spaced it close so as not to overheat that area. Keep in mind, no patio door was there and regular 8' ceiling. However, the years, the patio door was added and the ceiling went all the way up with the roof.

Neil

jim sokolovic

I've seen alot of kitchens...

that have no radiation installed. These are all older homes - maybe before there were microwaves and stoves were used more is the reason. Do heat load calcs consider the stove and fridge heat added? You might be very uncomfortable next Thanksgiving with the extra baseboard output you are considering? Have you tried to feel the temperature of the pipe leaving the baseboard - if it's considerably cooler than the pipe going to the baseboard, it may be a flow problem. If it's only slightly cooler, the baseboard may be undersized. We hadn't addressed this yet, maybe something more to consider?

Neil_5

Heat loss did not considere stove/microwave.

Pipe in and out is hot, so I don't think its a flow problem, if for some reason I am too hot next Thanksgiving, can't I close the damper during those time?

Currently the entire first and second floor is well insulated and windows are good/ draft are at min. My problem is the floors are cold (wood) because the basement windows needs replacing and walls insulating. I am thinking maybe I shuold leave that kitchen BB as it is UNTILL I seal up the basement THEN see how the kitchen feels?

ScottMP

Niel

I believe that you are correct and it is not a tees spacing or flow problem. You stated it was a convector and they installed baseboard to replace it. The convector had a higher output than the five feet of baseboard you have.

Think about a panel radiator.

Scott

To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"

Neil_5

To keep cost down and not use a panel radiator, can I use a High Output baseboard like the Rydon 958 unit which is almost 50% more BTU out that a regular BB