Consider shell & tube heat exchanger to reduce maintenance headaches from small passage plate&frame units. This will require additional space and have higher first cost but the building owner will thank you.
If your glycol/tower side is below freezing, how do you avoid freezing building side?
http://www.armstrongair.com/
Looks like mainly residential equipment. Their "corporate info" links to the Lennox website, so your rep may be able to give you some info.
I should clarify that delta-T for q-input is different. In a reciculating air system this would be the return (room) air-temp minus the heated-air-temp (in human comfort conditions may want to limit to around 95 deg-F so as not to melt your occupants).
Heat-lost = heat-input given steady-state conditions. In US units, heat loss, q = U x A x delta-T, and the heat input required is q = 1.08 x CFM x delta-T. That latter formula can be derived from the standard convective heat equation. delta-T is highest room temperature minus lowest design...
A small constant-temperature room air-conditioner condenser unit will usually be cooled with about 5 gpm chilled water. I am providing domestic-water backup connection which would be higher flow due to higher temp. I know I need backflow preventer. Question is will double check valve be...
Thanks krb & TXIceman for diving into ASHRAE 15. We are under the International mechanical code and I notice that it contains most of the ASHRAE items that you have been mentioning in one form or another....
Hmmm... boiler rep doesn't see an issue. He is saying that flue temp shouldn't get over 400deg-F (assuming conventional venting) and that the combustion chamber is surrounded by the water jacket. Wondering if sealed combustion is required? Chiller rep doesn't see any issues either. Gonna...
Anybody know what code issues I might run into by locating a 50 ton chiller in same room as two one-million btuh boilers? Someone seems to think there may be issues and one person has eluded to ASHRAE standard 15. This is in Indiana, USA. I am looking at a split type chiller system so...
Pressure-only measurement is not going to tell you the same thing as velocity/flow measurement. I think the original poster needs to elaborate on the application however.
Good basic description but.. geez, who still uses inclined manometers to measure pressure? Seems like Dwyer would put a plug in there for there Magnehelic gages.
Assume you mean paper dust. Be wary of cartridge design dust collectors as pleats can plug easily with paper dust. Tube style collectors are better bet and can be simple non-pulsating type. As in all dust collection apps, attention should be paid to minimizing the air required... careful...
Hopefully your area has a material exchange that you can list it in. In the state of Indiana this is run through the Department of Environmental Management. See:
http://www.in.gov/idem/imx/
I've always plyed with the idea of aquiring some of the used telephone poles which are periodically...
Have you thought of the noise issues?? I've seen HVAC trunks running at 3,500 fpm and double-wall (inside wall perforated with fiberglass fill) was the choice. As I recall elbows were 1.5-2x wide radius types probably to reduce pressure loss as well as have benefit of continuity in the noise...
Don't use plastic duct. That pretty much eliminates any grounding issues.
I doubt you could cavitate duct at pressures seen in a typical woodworking system since the duct will have to be strong enough to take the occasional wood-block careening through the system anyway. Blocking off all the...
Tape sucks since they all use adhesive - duct tape sucks the most since it doesn't even hold form like the aluminum stuff. Read the recent ASHRAE article.
Gasketed duct is great with Lindab ok for fine particles where likelyhood of cleaning out is low. If plugs are expected and you need to...
Application is central air-handlers in a university building. Apparently some here want to specify that hand-off-auto selector switches be installed for fractional horsepower motors such as freeze-protection pumps (hot water air-handler coils) and electrical closet exhaust fans. My argument is...
