Grizzly
14-12-2007, 02:24 AM
Hi Guys.
How many of you are starting to get problems now the cold weather is here like:-
Chillers overrunning their temp/ pressure controls due to overcondensing.
An even bigger problem is convincing the customer that I can't do a full maintenance log because the chiller won't load up. ( no point doing superheat readings or looking for flash gas) if the system isn't fully loaded.
I had a visit, I had to abandon the other day because the BMS System would not allow the chiller to run.
It wanted heating in the building and not cooling!
And NO I was not prepaired to override the BMS.
I was called to a system recently where a pair of
chillers were in alarm due to no water flow through them. It transpired that the BMS. Had a chiller lock out which was set to 5c. Which allows either of the 2 pumps to run or not!
As the ambient was nearer 2c the chillers were in alarm. A cup of tea and a biscuit with the facilities Enginner later the ambient temp had risen above 5c.
The BMS said pump 1 was running but the chillers were locked out on alarm. I went down several floors to get my Electrical test Kit. Upon arrival back on roof space found chiller 1 running with 2 available.
Confused I was but happy to leave it running.
I was subsiquently told that 1 of the 2 pumps had it's 3 fuses removed. Hence showing as running but chillers locked out. When I arrived back the second pump had been selected by the BMS and "all was well".
When I asked "what was wrong with the pump" I was told " Don't know just put the fuses back in"!!
Cheers Grizzly
How many of you are starting to get problems now the cold weather is here like:-
Chillers overrunning their temp/ pressure controls due to overcondensing.
An even bigger problem is convincing the customer that I can't do a full maintenance log because the chiller won't load up. ( no point doing superheat readings or looking for flash gas) if the system isn't fully loaded.
I had a visit, I had to abandon the other day because the BMS System would not allow the chiller to run.
It wanted heating in the building and not cooling!
And NO I was not prepaired to override the BMS.
I was called to a system recently where a pair of
chillers were in alarm due to no water flow through them. It transpired that the BMS. Had a chiller lock out which was set to 5c. Which allows either of the 2 pumps to run or not!
As the ambient was nearer 2c the chillers were in alarm. A cup of tea and a biscuit with the facilities Enginner later the ambient temp had risen above 5c.
The BMS said pump 1 was running but the chillers were locked out on alarm. I went down several floors to get my Electrical test Kit. Upon arrival back on roof space found chiller 1 running with 2 available.
Confused I was but happy to leave it running.
I was subsiquently told that 1 of the 2 pumps had it's 3 fuses removed. Hence showing as running but chillers locked out. When I arrived back the second pump had been selected by the BMS and "all was well".
When I asked "what was wrong with the pump" I was told " Don't know just put the fuses back in"!!
Cheers Grizzly