Trouble in Glencoe

Pumpguy

I have a customer with a 1930's vintage Duplex Nash Jennings Vacuum Heating Pump in their home. I have been servicing these pumps for abut 8 years now and the pumps are working just fine, but the customer is having ongoing controls problems.



I should add that this is a 2 pipe system with low returns and an auxiliary accumulator tank. The vacuum pumps discharge condensate to a small boiler feed unit feeding 2 small boilers that were installed just a few years ago.



The basic problem is the customer is frustrated because the controls are not operating the system properly. Most of the time the house is too cold, but there are times when it's too hot. I should add that supplemental electric heating is installed, but it's not enough to solve the problem.



There is an aquastat clamped to the return line just upstream of the auxiliary accumulator tank. It is set at 120 degrees. it's purpose is to prevent the vacuum pumps from running on demand of the vacuum switch when heating is not needed. Below 120 degrees, the circuit to the vacuum switch is open, and the vacuum pump operates on float only. I have

installed an aquastat override timer switch to bypass the aquastat to allow the customer to get vacuum on the system when it's cold.



The customer is frustrated with the un-even heating and also the need to manually operate the pump's switches to get it to operate. I have suggested that this aquastat be replaced with an outdoor temperature sensing device that would complete the pump's vacuum switch circuit at maybe 40-45 degrees. This has not been done.



This system has Johnson Controls pneumatic controls. I do not know enough about the controls aspect of this system to get involved with anything beyond the basic pump control switches. Is there anyone that serves Northeastern Illinois that would be willing to look at

this job and work with me to solve this customer's problem?



Thanks for any and all help.

Dennis Pataki

OAK SERVICES COMPANY

PHONE: 1-815 678 7734

FAX: 1-815 678 2494

EMAIL: <a href="mailto:oakservcs@aol.com">oakservcs@aol.com</a>

The Steam Whisperer (Formerly Boilerpro)

I'm in Chicago,

Have the Client give me a call.  I would certainly get rid of that aquastat on the return.  That's backwards, the heat is already on when that pipe finally gets hot, so the system is already working improperly at that point.  The vacuum pump should be on well before the boiler fires. 

EBEBRATT-Ed

pneumatics

The trouble may be with the pneumatic controls. Most people will probably tell you to rip them out They are the ones that don't know how to work on them.. Pneumatics are fairly simple and reliable and dependable . They usually need a little service, keeping the air lines free of oil and water and calabrating the controls once or twice a year and they will work well.

The trick is to find someone old enough to know how to work on that equipment. I have no doubt you could do it with a little training if you are unfamalier with the controls.

I'm plenty old enough but to far away to help.