Security Seal Facebook Twitter GooglePlus Pinterest Newsletter Sign-up
The Wall
RJ

RJ

Joined on February 3, 2007

Last Post on July 18, 2014

Contact User

Recent Posts

« 1 ... 13 14 15 16 17 18 »

foot of head

@ August 27, 2008 10:13 PM in Anyone heard this rule of thumb?

If a pipe is filled with water 2.31 ft. the pressure will be 1psig. It is recommended to have at least 5 psig. at the highest point of the system , to help with air removal. Example: A system with a pump in the basement and a 20' height to the top of a solar panel would figure as 20'divided by 2.31 = 8.6l lbs. add 5 lbs. total static press. = 13.61 lbs.

flue

@ August 20, 2008 10:37 PM in Flue gas booster fan

Get a hold of these guys. www.selkirk.com 800-992-vent (8368).

@ August 20, 2008 10:27 PM in Controling the heat in individual steam heated apartments

lets make that radiators

Danfoss

@ August 20, 2008 10:25 PM in Controling the heat in individual steam heated apartments

If using Danfoss air vent control valves on a 1 pipe system you will need to cycle the boiler off numerous times allowing air to reenter the radiator or baseboard unit. That's the only way it will work. If you dont the radiarors will never shut off.

reset

@ August 20, 2008 9:44 PM in Chilled water reset controls... (ME)

Johnson controls has a A350/S350 series you can use to reset chill water.

sequence

@ January 14, 2008 6:31 PM in 2 pipe Hydronic system

How does the system you have seen work ,what is the sequence of oper.

2 pipe hydonic system

@ January 13, 2008 10:56 PM in 2 pipe Hydronic system

I recently looked at a 12 story condo bldg. circa 1967. It has 12 Hydrotherm modular boilers for heating. 6 of these are also piped through heat exchangers for domestic HW. There are 2 Carrier recip. chillers. the old style control system switches from heating to cooling depending on OA temp. The system does not have 3 way changeover valves or chiller bypass valves. The system does have check valves on the suction side of the chill water pumps. It looks like the mechanical side was originally designed as a manual changeover system, but current engineer is running it as an auto changeover system. There is a control to keep the chillers off line untill loop temp. drops below 100 degrees, but in the heating mode,hot water is migrating into the chiller. I am thinking that maybe the check valves are leaking through. Anyone seen a system like this?

U.A.

@ January 9, 2008 10:03 PM in Pipe sizing(supply & return) for Carrier 42ck fan coil ac units

If your a member of the U.A. you can order this book on line (Hydronic Heating and Cooling.) It's got it all. $40.00. www.ua.org

air

@ January 6, 2008 8:03 PM in HELP! How to purge air from basement loop?

Always shut the pump off when bleeding air from any HW baseboard or terminal unit. If you dont have a purge valve ahead of the return shut off valve you will need to install one. Until you have time to make permanent repairs you can install a saddle tap on the baseboard piping, The type used for tapping into water lines to hook up ice machines on refrigerators.

Air

@ January 1, 2008 2:19 PM in hydronic system-air in lines

Look on your exp. tank for a 1 inch plug unscrew this, you will find a tire gauge looking fitting. Push in stem with your thumbnail, if water comes out you have a defective bladder and will need to relace bladder or tank. If you have air check with a tire guage you want 12 psig. If it is low add air, you can use a bicycle pump. IF you have the old style compression tank look for pinhole leaks at top of tank. Both would cause the relief valve to open, causing fresh water to fill boiler through the PRV (fill valve). also check the fill valve strainer if this is plugged or if valve is corroded and pipng to boiler is plugged it will cause valve to overfeed. Make sure the exp. tank is on the suction side of system.

piping

@ December 28, 2007 6:11 PM in Gurgling & Spitting Steam Radiator

check your header piping at the boiler, look in Dan,s Deadman,s book around page 54. If your pipng is wromg you may be entraining water up the main.

piping

@ December 28, 2007 6:10 PM in Gurgling & Spitting Steam Radiator

check your header piping at the boiler, look in Dan,s Deadman,s book around page 54. If your pipng is wromg you may be entraining water up the main.

@ December 28, 2007 4:52 PM in flue damper

damper: Johnson Controls makes one ,just install and plug into your existing igniton control. call 1-800-482-2778.

gpm

@ October 4, 2007 9:27 AM in gpm in pipes

On a water service line it all begins with the size of your water meter. For example, an 1 1/4 line with a 1 inch meter will deliver 20gpm at 50 psi static pressure, figuring a line 75 feet long. Call A.O. Smith tech. line for sizing tables. 1-800-527-1953.

header

@ September 28, 2007 10:41 PM in two pipe- air vent

refresh my memory about the dropped header principal.

@ September 5, 2007 10:40 PM in circuit setter

Agree with Paul, Save the grief. repipe using primary secondary loop with a primary pump and a pump for each boiler, top it off with a HEATTIMER logic control, this type of control will automatically rotate boilers.

cross connection

@ August 27, 2007 7:51 PM in Steam boiler feeds automatically (unwanted)

What ever you decide, it sounds like you have a cross connection, you should have a backflow device in the line between your HWH and the boiler.

Domestic Boiler recommendations

@ August 26, 2007 8:40 PM in Domestic Boiler replacement

Have a customer that wants to replace a 1,2oo,ooo BTU Teledyne Larrs boiler with a high efficiency (Domestic hot water) boiler. looking for a quality boiler.

wireless

@ August 7, 2007 10:48 PM in tstat

Be careful, wireless systems have problems in buildings that have alot of concrete with rebarb. Also buildings that have cell phone comm. equip. on roof.

pressure controls

@ August 7, 2007 10:38 PM in Refrigerant leaks

One of the biggest sources of leaks is the service valves you might have just taken your gages off of. Make sure all caps are tightly sealed. I just finished a job on 2 large Kramer ]freezers where both Cond. units had leaks in the bellows of the defrost pressure controls. A good leak detector will run about $500.00. Dont like the dyes, gets all over your guages and smells horrible. Pressure test with 150-200psig of nitrogen or use leak detector.

Balance valves

@ July 5, 2007 8:06 PM in Any reason NOT to always use full port ball valves?

The difference is Bell&Gosset or T&A or whatever make, are precision engineered valves, the smaller valves do employ ball valve construction but are designed different than regular ball valves. they also have have test ports to hook up a circut setter meter (B&G RO-4). the larger flange valves employ globe valve construction. A properly installed VAV system needs circut setters on the reheat coils to acheive a properly balanced system.

@ July 4, 2007 9:59 PM in Any reason NOT to always use full port ball valves?

I agree on the use of a red. port ball valve for purging. Using a ball valve for balancing is not ideal, leaving the valve in a partially closed position is not good for the teflon seal rings. Should use a balancing (circut setter). Agreeing with Paul P. Proportional control is acheived by using a globe style valve.
« 1 ... 13 14 15 16 17 18 »