SAN FRANCISCO (CBS SF) — Thousands of Kaiser health union workers in the San Francisco Bay Area and across Northern California joined picket lines Friday morning in a show of solidarity with striking facility engineers.

Last weekend, the health provider reached new labor deals with the unions representing the system’s pharmacists and hospital workers.

READ MORE: KPIX Reporters Remember Slain Security Guard Kevin Nishita; 'Just the Kindest Man'

However, Kaiser officials remain at odds on a new labor pact with the union representing facility engineers, who keep everything from boilers and refrigeration to air conditioning and generators up and running. Their contract expired in September and they have been on strike for weeks.

About 20,000 nurses and thousands of mental health professionals, represented by National Union of Healthcare Workers, are expected to join in the sympathy strike.

Among those joining the picketers on Friday was Jason Lechner, a staff addiction medical specialist.

READ MORE: UPDATE: News Crew Security Guard Shot in Oakland Dies From Injuries; Photo of Suspect Vehicle Released

“Given the engineers have been out here (on the picket line) for 63 days now and the pharmacists are dealing with union issues,” he said. “Our clinic, all the mental health clinicians, are dealing with union issues, you can say you are bargaining in good faith, the results are in what shows up (pointing at the picket line).”

The company claims the stumbling point in negotiations has been the engineers salary demands.

“The union insist it receive much more — in some cases nearly two times more — than other union agreements covering Kaiser Permanente employees,” the company said in a statement sent to KPIX 5. “We are optimistic we can resolve the remaining issues with Local 39.”

The solidarity walkout began on Thursday. Michelle Gaskill-Hames, senior vice president of hospital and health plan operations at Kaiser Permanente Northern California, issued a video statement on Thursday saying the system had taken steps to maintain a high level of care for its patients.

MORE NEWS: Burlingame Shoppers Show Up for Small Business Saturday

“We have plans in place to provide care despite the unions call for staff to walk away from their patients,” she said. “Care will be provided by physicians and clinical managers with the support of trained and qualified contingency staff.”