Recent content by wj33

Can the water flow to a condenser be varied? The unit in question is approx 500 TR Centrifugal, Trane I cannot find any Trane lit that covers this

Thanks for the link. I am however looking for a unit available in the U.S. I know they are available with hydronic or steam heat but have not seen any offering electric heat. I have a project that could use units with electric heat.

Do any manufacturers in the US offer elec heat as an option in console fan coil units?

Yes the unit had been shut down for a while, it is a backup chiller Tubes approx 60 cracked in the evap. I know this can happen if the chilled water pump goes out but this happened with only water flowing through condenser.

Is it possible to freeze the evaporator in a single stage absorption chiller with the unit off but with condenser pump on and tower water flowing through the condenser and chilled water pump off and no water flow through the evaporator?

I have a closed circuit water loop on a heat pump system. Pumps are located in basement and top of system is 30 floors high. Water temperature in the loop does not fluctuate more than 25 deg F. The system has no good way to remove air. Although the preferred location for an air separator is...

I am looking for some history on McQuays screw chiller (mono screw) relative to compressor failures they have had and causes. I believe this compressor is no longer manufactured but was approx 5 years ago

We are controlling an existing cooling unit which has to be energized or de-energized by closing a circuit for approx 2 secs (momentary contact). The thermostat controlling the units operation energizes/de-energizes a relay. To provide a momentary closure to the cooling unit we are using a...

Each time a set point is reached a relay is switched. At this time we need to reset a delay timer to complete another circuit function.

I am setting up a circuit where I need to have a timer drop out when a relay switches. Is there a relay I can use that will have a deadband time of approx .5 sec?

I think they ran deadhead for some time. They lost seals a few times. Likely while they were making steam when the pump was churning.

The pump is a small flow, 80 gpm water pump, close coupled, water service. It has a mechanical seal with no provision for flow control to the seal. My concern is when discharge is restricted, that there is sufficient flow in seal area on the back side of the impeller to provide adequate...

On an end suction single stage centrifugal pump, how can you determine the pressure at the mechanical seal? Also what would be the approximate flow around the seal relative to gpm through the pump?

try www.robur.com. They make a small gas fired absorption unit. They have been around for a long time.

A cooling tower's capacity must match the flow rate from the chiller and the heat ( flow rate x temp rise in chiller) and reject this heat to the atmosphere. You must tell tower vendors what your flow rate is. This is determined by the limitations of the chiller, pressure drop etc. If a...